NOAA SWPC Alertes, surveillances et avertissements

Le Centre de prévision National Oceanic and Atmospheric Administration Space Weather (NOAA SWPC) est l'organisme gouvernemental de la météorologie spatiale officielle des États-Unis qui fournit des alertes pour les perturbations de la météo spatiale. Ci-dessous vous trouverez les dernières alertes météorologiques de l'espace émis par la NOAA SWPC.

vendredi, 5 juin 2026

20:09 UTC

Space Weather Message Code: ALTK05
Serial Number: 2025
Issue Time: 2026 Jun 05 2009 UTC

ALERT: Geomagnetic K-index of 5
Threshold Reached: 2026 Jun 05 2002 UTC
Synoptic Period: 1800-2100
Active Warning: YES
Noaa Scale: G1 - Minor
Comment:

NOAA Scale: G1 - Minor

NOAA Space Weather Scale descriptions can be found at
www.swpc.noaa.gov/noaa-scales-explanation

Potential Impacts: Area of impact primarily poleward of 60 degrees Geomagnetic Latitude.
Induced Currents - Weak power grid fluctuations can occur.
Spacecraft - Minor impact on satellite operations possible.
Aurora - Aurora may be visible at high latitudes, i.e., northern tier of the U.S. such as northern Michigan and Maine.

18:54 UTC

Space Weather Message Code: WARK04
Serial Number: 5360
Issue Time: 2026 Jun 05 1854 UTC

EXTENDED WARNING: Geomagnetic K-index of 4 expected
Extension to Serial Number: 5359
Valid From: 2026 Jun 05 0434 UTC
Now Valid Until: 2026 Jun 06 0900 UTC
Warning Condition: Persistence




NOAA Space Weather Scale descriptions can be found at
www.swpc.noaa.gov/noaa-scales-explanation

Potential Impacts: Area of impact primarily poleward of 65 degrees Geomagnetic Latitude.
Induced Currents - Weak power grid fluctuations can occur.
Aurora - Aurora may be visible at high latitudes such as Canada and Alaska.

18:52 UTC

Space Weather Message Code: WATA30
Serial Number: 274
Issue Time: 2026 Jun 05 1852 UTC

WATCH: Geomagnetic Storm Category G2 Predicted
Highest Storm Level Predicted by Day:
Jun 06: G2 (Moderate) Jun 07: None (Below G1) Jun 08: None (Below G1)
THIS SUPERSEDES ANY/ALL PRIOR WATCHES IN EFFECT
Comment:



NOAA Space Weather Scale descriptions can be found at
www.swpc.noaa.gov/noaa-scales-explanation

Potential Impacts: Area of impact primarily poleward of 55 degrees Geomagnetic Latitude.
Induced Currents - Power grid fluctuations can occur. High-latitude power systems may experience voltage alarms.
Spacecraft - Satellite orientation irregularities may occur; increased drag on low Earth-orbit satellites is possible.
Radio - HF (high frequency) radio propagation can fade at higher latitudes.
Aurora - Aurora may be seen as low as New York to Wisconsin to Washington state.

17:21 UTC

Space Weather Message Code: WARK06
Serial Number: 662
Issue Time: 2026 Jun 05 1721 UTC

EXTENDED WARNING: Geomagnetic K-index of 6 expected
Extension to Serial Number: 661
Valid From: 2026 Jun 05 1437 UTC
Now Valid Until: 2026 Jun 06 0300 UTC
Warning Condition: Persistence


NOAA Scale: G2 - Moderate

NOAA Space Weather Scale descriptions can be found at
www.swpc.noaa.gov/noaa-scales-explanation

Potential Impacts: Area of impact primarily poleward of 55 degrees Geomagnetic Latitude.
Induced Currents - Power grid fluctuations can occur. High-latitude power systems may experience voltage alarms.
Spacecraft - Satellite orientation irregularities may occur; increased drag on low Earth-orbit satellites is possible.
Radio - HF (high frequency) radio propagation can fade at higher latitudes.
Aurora - Aurora may be seen as low as New York to Wisconsin to Washington state.

17:19 UTC

Space Weather Message Code: WARK05
Serial Number: 2239
Issue Time: 2026 Jun 05 1719 UTC

EXTENDED WARNING: Geomagnetic K-index of 5 expected
Extension to Serial Number: 2238
Valid From: 2026 Jun 05 1228 UTC
Now Valid Until: 2026 Jun 06 0600 UTC
Warning Condition: Persistence


NOAA Scale: G1 - Minor

NOAA Space Weather Scale descriptions can be found at
www.swpc.noaa.gov/noaa-scales-explanation

Potential Impacts: Area of impact primarily poleward of 60 degrees Geomagnetic Latitude.
Induced Currents - Weak power grid fluctuations can occur.
Spacecraft - Minor impact on satellite operations possible.
Aurora - Aurora may be visible at high latitudes, i.e., northern tier of the U.S. such as northern Michigan and Maine.

17:16 UTC

Space Weather Message Code: WARK07
Serial Number: 150
Issue Time: 2026 Jun 05 1716 UTC

WARNING: Geomagnetic K-index of 7 or greater expected
Valid From: 2026 Jun 05 1714 UTC
Valid To: 2026 Jun 05 2359 UTC
Warning Conditions: Onset
Noaa Scale: G3 - Greater
Comment:

NOAA Scale: G3 - Greater

16:39 UTC

Space Weather Message Code: ALTK06
Serial Number: 718
Issue Time: 2026 Jun 05 1639 UTC

ALERT: Geomagnetic K-index of 6
Threshold Reached: 2026 Jun 05 1638 UTC
Synoptic Period: 1500-1800
Active Warning: YES
Noaa Scale: G2 - Moderate
Comment:

NOAA Scale: G2 - Moderate

NOAA Space Weather Scale descriptions can be found at
www.swpc.noaa.gov/noaa-scales-explanation

Potential Impacts: Area of impact primarily poleward of 55 degrees Geomagnetic Latitude.
Induced Currents - Power grid fluctuations can occur. High-latitude power systems may experience voltage alarms.
Spacecraft - Satellite orientation irregularities may occur; increased drag on low Earth-orbit satellites is possible.
Radio - HF (high frequency) radio propagation can fade at higher latitudes.
Aurora - Aurora may be seen as low as New York to Wisconsin to Washington state.

16:21 UTC

Space Weather Message Code: ALTK05
Serial Number: 2024
Issue Time: 2026 Jun 05 1621 UTC

ALERT: Geomagnetic K-index of 5
Threshold Reached: 2026 Jun 05 1620 UTC
Synoptic Period: 1500-1800
Active Warning: YES
Noaa Scale: G1 - Minor
Comment:

NOAA Scale: G1 - Minor

NOAA Space Weather Scale descriptions can be found at
www.swpc.noaa.gov/noaa-scales-explanation

Potential Impacts: Area of impact primarily poleward of 60 degrees Geomagnetic Latitude.
Induced Currents - Weak power grid fluctuations can occur.
Spacecraft - Minor impact on satellite operations possible.
Aurora - Aurora may be visible at high latitudes, i.e., northern tier of the U.S. such as northern Michigan and Maine.

14:41 UTC

Space Weather Message Code: WARK06
Serial Number: 661
Issue Time: 2026 Jun 05 1441 UTC

WARNING: Geomagnetic K-index of 6 expected
Valid From: 2026 Jun 05 1437 UTC
Valid To: 2026 Jun 05 2100 UTC
Warning Conditions: Onset
Noaa Scale: G2 - Moderate
Comment:

NOAA Scale: G2 - Moderate

NOAA Space Weather Scale descriptions can be found at
www.swpc.noaa.gov/noaa-scales-explanation

Potential Impacts: Area of impact primarily poleward of 55 degrees Geomagnetic Latitude.
Induced Currents - Power grid fluctuations can occur. High-latitude power systems may experience voltage alarms.
Spacecraft - Satellite orientation irregularities may occur; increased drag on low Earth-orbit satellites is possible.
Radio - HF (high frequency) radio propagation can fade at higher latitudes.
Aurora - Aurora may be seen as low as New York to Wisconsin to Washington state.

13:35 UTC

Space Weather Message Code: ALTK05
Serial Number: 2023
Issue Time: 2026 Jun 05 1335 UTC

ALERT: Geomagnetic K-index of 5
Threshold Reached: 2026 Jun 05 1327 UTC
Synoptic Period: 1200-1500
Active Warning: YES
Noaa Scale: G1 - Minor
Comment:

NOAA Scale: G1 - Minor

NOAA Space Weather Scale descriptions can be found at
www.swpc.noaa.gov/noaa-scales-explanation

Potential Impacts: Area of impact primarily poleward of 60 degrees Geomagnetic Latitude.
Induced Currents - Weak power grid fluctuations can occur.
Spacecraft - Minor impact on satellite operations possible.
Aurora - Aurora may be visible at high latitudes, i.e., northern tier of the U.S. such as northern Michigan and Maine.

12:58 UTC

Space Weather Message Code: ALTK04
Serial Number: 2664
Issue Time: 2026 Jun 05 1258 UTC

ALERT: Geomagnetic K-index of 4
Threshold Reached: 2026 Jun 05 1253 UTC
Synoptic Period: 1200-1500
Active Warning: YES
Comment:



NOAA Space Weather Scale descriptions can be found at
www.swpc.noaa.gov/noaa-scales-explanation

Potential Impacts: Area of impact primarily poleward of 65 degrees Geomagnetic Latitude.
Induced Currents - Weak power grid fluctuations can occur.
Aurora - Aurora may be visible at high latitudes such as Canada and Alaska.

12:30 UTC

Space Weather Message Code: WARK05
Serial Number: 2238
Issue Time: 2026 Jun 05 1230 UTC

WARNING: Geomagnetic K-index of 5 expected
Valid From: 2026 Jun 05 1228 UTC
Valid To: 2026 Jun 05 2100 UTC
Warning Conditions: Onset
Noaa Scale: G1 - Minor
Comment:

NOAA Scale: G1 - Minor

NOAA Space Weather Scale descriptions can be found at
www.swpc.noaa.gov/noaa-scales-explanation

Potential Impacts: Area of impact primarily poleward of 60 degrees Geomagnetic Latitude.
Induced Currents - Weak power grid fluctuations can occur.
Spacecraft - Minor impact on satellite operations possible.
Aurora - Aurora may be visible at high latitudes, i.e., northern tier of the U.S. such as northern Michigan and Maine.

05:13 UTC

Space Weather Message Code: SUMSUD
Serial Number: 300
Issue Time: 2026 Jun 05 0513 UTC

SUMMARY: Geomagnetic Sudden Impulse
Observed: 2026 Jun 05 0511 UTC
Deviation: 70 nT
Station: MEA
Comment:

04:35 UTC

Space Weather Message Code: WARK04
Serial Number: 5359
Issue Time: 2026 Jun 05 0435 UTC

WARNING: Geomagnetic K-index of 4 expected
Valid From: 2026 Jun 05 0434 UTC
Valid To: 2026 Jun 06 0300 UTC
Warning Conditions: Onset
Comment:



NOAA Space Weather Scale descriptions can be found at
www.swpc.noaa.gov/noaa-scales-explanation

Potential Impacts: Area of impact primarily poleward of 65 degrees Geomagnetic Latitude.
Induced Currents - Weak power grid fluctuations can occur.
Aurora - Aurora may be visible at high latitudes such as Canada and Alaska.

04:33 UTC

Space Weather Message Code: WARSUD
Serial Number: 255
Issue Time: 2026 Jun 05 0433 UTC

WARNING: Geomagnetic Sudden Impulse expected
Valid From: 2026 Jun 05 0450 UTC
Valid To: 2026 Jun 05 1515 UTC
Ip Shock: 2026-06-05 04:31
Comment:

mercredi, 3 juin 2026

22:38 UTC

Space Weather Message Code: WARK04
Serial Number: 5358
Issue Time: 2026 Jun 03 2238 UTC

WARNING: Geomagnetic K-index of 4 expected
Valid From: 2026 Jun 03 2237 UTC
Valid To: 2026 Jun 04 0600 UTC
Warning Conditions: Onset
Comment:



NOAA Space Weather Scale descriptions can be found at
www.swpc.noaa.gov/noaa-scales-explanation

Potential Impacts: Area of impact primarily poleward of 65 degrees Geomagnetic Latitude.
Induced Currents - Weak power grid fluctuations can occur.
Aurora - Aurora may be visible at high latitudes such as Canada and Alaska.

14:52 UTC

Space Weather Message Code: WATA50
Serial Number: 98
Issue Time: 2026 Jun 03 1452 UTC

WATCH: Geomagnetic Storm Category G3 Predicted
Highest Storm Level Predicted by Day:
Jun 04: G3 (Strong) Jun 05: G3 (Strong) Jun 06: None (Below G1)
THIS SUPERSEDES ANY/ALL PRIOR WATCHES IN EFFECT
Comment:

11:59 UTC

Space Weather Message Code: SUMX01
Serial Number: 218
Issue Time: 2026 Jun 03 1159 UTC

SUMMARY: X-ray Event exceeded X1
Begin Time: 2026 Jun 03 1119 UTC
Maximum Time: 2026 Jun 03 1128 UTC
End Time: 2026 Jun 03 1135 UTC
Xray Class: X1.0
Optical Class:
Location: N17W19
Noaa Scale: R3 - Strong
Comment: GOES-18 outage so using GOES-19


GOES-18 outage so using GOES-19NOAA Scale: R3 - Strong

NOAA Space Weather Scale descriptions can be found at
www.swpc.noaa.gov/noaa-scales-explanation

Potential Impacts: Area of impact consists of large portions of the sunlit side of Earth, strongest at the sub-solar point.
Radio - Wide area blackout of HF (high frequency) radio communication for about an hour.

11:47 UTC

Space Weather Message Code: SUM10R
Serial Number: 917
Issue Time: 2026 Jun 03 1147 UTC

SUMMARY: 10cm Radio Burst
Begin Time: 2026 Jun 03 1121 UTC
Maximum Time: 2026 Jun 03 1122 UTC
End Time: 2026 Jun 04 1123 UTC
Peak Flux: 250 sfu
Duration: 2 minutes
Latest Penticton Noon Flux: 146 sfu
Comment:

11:41 UTC

Space Weather Message Code: ALTXMF
Serial Number: 531
Issue Time: 2026 Jun 03 1141 UTC

ALERT: X-Ray Flux exceeded M5
Threshold Reached: 2026 Jun 03 1141 UTC
Noaa Scale: R2 - Moderate
Comment:

NOAA Scale: R2 - Moderate

NOAA Space Weather Scale descriptions can be found at
www.swpc.noaa.gov/noaa-scales-explanation

Potential Impacts: Area of impact centered on sub-solar point on the sunlit side of Earth. Extent of blackout of HF (high frequency) radio communication dependent upon current X-ray Flux intensity. For real-time information on affected area and expected duration please see http://www.swpc.noaa.gov/products/d-region-absorption-predictions-d-rap.

07:29 UTC

Space Weather Message Code: ALTTP2
Serial Number: 1497
Issue Time: 2026 Jun 03 0729 UTC

ALERT: Type II Radio Emission
Begin Time: 2026 Jun 03 0657 UTC
Estimate Velocity: 313 km/s
Comment:

07:17 UTC

Space Weather Message Code: SUM10R
Serial Number: 916
Issue Time: 2026 Jun 03 0717 UTC

SUMMARY: 10cm Radio Burst
Begin Time: 2026 Jun 03 0657 UTC
Maximum Time: 2026 Jun 03 0657 UTC
End Time: 2026 Jun 03 0700 UTC
Peak Flux: 540 sfu
Duration: 3 minutes
Latest Penticton Noon Flux: 146 sfu
Comment: Castelli-U signature. Corrected duration.


Castelli-U signature. Corrected duration.

07:15 UTC

Space Weather Message Code: SUMXM5
Serial Number: 318
Issue Time: 2026 Jun 03 0715 UTC

SUMMARY: X-ray Event exceeded M5
Begin Time: 2026 Jun 03 0648 UTC
Maximum Time: 2026 Jun 03 0700 UTC
End Time: 2026 Jun 03 0707 UTC
Xray Class: M7.7
Optical Class: 2B
Location: N08W14
Noaa Scale: R2 - Moderate
Comment:

NOAA Scale: R2 - Moderate

NOAA Space Weather Scale descriptions can be found at
www.swpc.noaa.gov/noaa-scales-explanation

Potential Impacts: Area of impact centered primarily on sub-solar point on the sunlit side of Earth.
Radio - Limited blackout of HF (high frequency) radio communication for tens of minutes.

07:10 UTC

Space Weather Message Code: SUM10R
Serial Number: 916
Issue Time: 2026 Jun 03 0710 UTC

SUMMARY: 10cm Radio Burst
Begin Time: 2026 Jun 03 0657 UTC
Maximum Time: 2026 Jun 03 0657 UTC
End Time: 2026 Jun 03 0658 UTC
Peak Flux: 540 sfu
Duration: 1 minutes
Latest Penticton Noon Flux: 146 sfu
Comment: Castelli-U signature


Castelli-U signature

07:00 UTC

Space Weather Message Code: ALTXMF
Serial Number: 530
Issue Time: 2026 Jun 03 0700 UTC

ALERT: X-Ray Flux exceeded M5
Threshold Reached: 2026 Jun 03 0700 UTC
Noaa Scale: R2 - Moderate
Comment:

NOAA Scale: R2 - Moderate

NOAA Space Weather Scale descriptions can be found at
www.swpc.noaa.gov/noaa-scales-explanation

Potential Impacts: Area of impact centered on sub-solar point on the sunlit side of Earth. Extent of blackout of HF (high frequency) radio communication dependent upon current X-ray Flux intensity. For real-time information on affected area and expected duration please see http://www.swpc.noaa.gov/products/d-region-absorption-predictions-d-rap.

02:15 UTC

Space Weather Message Code: SUM10R
Serial Number: 915
Issue Time: 2026 Jun 03 0215 UTC

SUMMARY: 10cm Radio Burst
Begin Time: 2026 Jun 03 0126 UTC
Maximum Time: 2026 Jun 03 0130 UTC
End Time: 2026 Jun 04 0131 UTC
Peak Flux: 360 sfu
Duration: 5 minutes
Latest Penticton Noon Flux: 146 sfu
Comment:

01:56 UTC

Space Weather Message Code: SUMXM5
Serial Number: 317
Issue Time: 2026 Jun 03 0156 UTC

SUMMARY: X-ray Event exceeded M5
Begin Time: 2026 Jun 03 0122 UTC
Maximum Time: 2026 Jun 03 0136 UTC
End Time: 2026 Jun 04 0143 UTC
Xray Class: M9.3
Optical Class: sf
Location: N13W05
Noaa Scale: R2 - Moderate
Comment:

NOAA Scale: R2 - Moderate

NOAA Space Weather Scale descriptions can be found at
www.swpc.noaa.gov/noaa-scales-explanation

Potential Impacts: Area of impact centered primarily on sub-solar point on the sunlit side of Earth.
Radio - Limited blackout of HF (high frequency) radio communication for tens of minutes.

01:43 UTC

Space Weather Message Code: ALTTP4
Serial Number: 710
Issue Time: 2026 Jun 03 0143 UTC

ALERT: Type IV Radio Emission
Begin Time: 2026 Jun 03 0122 UTC
Comment:

01:42 UTC

Space Weather Message Code: ALTTP2
Serial Number: 1496
Issue Time: 2026 Jun 03 0142 UTC

ALERT: Type II Radio Emission
Begin Time: 2026 Jun 03 0057 UTC
Estimate Velocity: 253 km/s
Comment:

01:37 UTC

Space Weather Message Code: ALTXMF
Serial Number: 529
Issue Time: 2026 Jun 03 0137 UTC

ALERT: X-Ray Flux exceeded M5
Threshold Reached: 2026 Jun 03 0131 UTC
Noaa Scale: R2 - Moderate
Comment:

NOAA Scale: R2 - Moderate

NOAA Space Weather Scale descriptions can be found at
www.swpc.noaa.gov/noaa-scales-explanation

Potential Impacts: Area of impact centered on sub-solar point on the sunlit side of Earth. Extent of blackout of HF (high frequency) radio communication dependent upon current X-ray Flux intensity. For real-time information on affected area and expected duration please see http://www.swpc.noaa.gov/products/d-region-absorption-predictions-d-rap.

mardi, 2 juin 2026

17:18 UTC

Space Weather Message Code: ALTTP2
Serial Number: 1495
Issue Time: 2026 Jun 02 1718 UTC

ALERT: Type II Radio Emission
Begin Time: 2026 Jun 02 1652 UTC
Estimate Velocity: 631 km/s
Comment: Uncertain if the sweep was associated with a limb event or an M3 solar flare that occurred at similar times.


Uncertain if the sweep was associated with a limb event or an M3 solar flare that occurred at similar times.

16:57 UTC

Space Weather Message Code: SUM10R
Serial Number: 914
Issue Time: 2026 Jun 02 1657 UTC

SUMMARY: 10cm Radio Burst
Begin Time: 2026 Jun 02 1642 UTC
Maximum Time: 2026 Jun 02 1642 UTC
End Time: 2026 Jun 02 1643 UTC
Peak Flux: 150 sfu
Duration: 1 minutes
Latest Penticton Noon Flux: 137 sfu
Comment: COR for end date. Event only lasted 1 minute.


COR for end date. Event only lasted 1 minute.

16:54 UTC

Space Weather Message Code: SUM10R
Serial Number: 914
Issue Time: 2026 Jun 02 1654 UTC

SUMMARY: 10cm Radio Burst
Begin Time: 2026 Jun 02 1642 UTC
Maximum Time: 2026 Jun 02 1642 UTC
End Time: 2026 Jun 03 1643 UTC
Peak Flux: 150 sfu
Duration: 1 minutes
Latest Penticton Noon Flux: 137 sfu
Comment:

lundi, 1 juin 2026

17:54 UTC

Space Weather Message Code: WARK04
Serial Number: 5357
Issue Time: 2026 Jun 01 1754 UTC

WARNING: Geomagnetic K-index of 4 expected
Valid From: 2026 Jun 01 1753 UTC
Valid To: 2026 Jun 02 0000 UTC
Warning Conditions: Onset
Comment:



NOAA Space Weather Scale descriptions can be found at
www.swpc.noaa.gov/noaa-scales-explanation

Potential Impacts: Area of impact primarily poleward of 65 degrees Geomagnetic Latitude.
Induced Currents - Weak power grid fluctuations can occur.
Aurora - Aurora may be visible at high latitudes such as Canada and Alaska.

samedi, 30 mai 2026

20:36 UTC

Space Weather Message Code: ALTK04
Serial Number: 2663
Issue Time: 2026 May 30 2036 UTC

ALERT: Geomagnetic K-index of 4
Threshold Reached: 2026 May 30 2035 UTC
Synoptic Period: 1800-2100
Active Warning: YES
Comment:



NOAA Space Weather Scale descriptions can be found at
www.swpc.noaa.gov/noaa-scales-explanation

Potential Impacts: Area of impact primarily poleward of 65 degrees Geomagnetic Latitude.
Induced Currents - Weak power grid fluctuations can occur.
Aurora - Aurora may be visible at high latitudes such as Canada and Alaska.

18:52 UTC

Space Weather Message Code: WARK04
Serial Number: 5356
Issue Time: 2026 May 30 1852 UTC

WARNING: Geomagnetic K-index of 4 expected
Valid From: 2026 May 30 1851 UTC
Valid To: 2026 May 31 0600 UTC
Warning Conditions: Onset
Comment:



NOAA Space Weather Scale descriptions can be found at
www.swpc.noaa.gov/noaa-scales-explanation

Potential Impacts: Area of impact primarily poleward of 65 degrees Geomagnetic Latitude.
Induced Currents - Weak power grid fluctuations can occur.
Aurora - Aurora may be visible at high latitudes such as Canada and Alaska.

vendredi, 29 mai 2026

19:52 UTC

Space Weather Message Code: ALTK04
Serial Number: 2662
Issue Time: 2026 May 29 1952 UTC

ALERT: Geomagnetic K-index of 4
Threshold Reached: 2026 May 29 1949 UTC
Synoptic Period: 1800-2100
Active Warning: YES
Comment:



NOAA Space Weather Scale descriptions can be found at
www.swpc.noaa.gov/noaa-scales-explanation

Potential Impacts: Area of impact primarily poleward of 65 degrees Geomagnetic Latitude.
Induced Currents - Weak power grid fluctuations can occur.
Aurora - Aurora may be visible at high latitudes such as Canada and Alaska.

19:32 UTC

Space Weather Message Code: WARK04
Serial Number: 5355
Issue Time: 2026 May 29 1932 UTC

WARNING: Geomagnetic K-index of 4 expected
Valid From: 2026 May 29 1932 UTC
Valid To: 2026 May 30 0900 UTC
Warning Conditions: Onset
Comment:



NOAA Space Weather Scale descriptions can be found at
www.swpc.noaa.gov/noaa-scales-explanation

Potential Impacts: Area of impact primarily poleward of 65 degrees Geomagnetic Latitude.
Induced Currents - Weak power grid fluctuations can occur.
Aurora - Aurora may be visible at high latitudes such as Canada and Alaska.

05:41 UTC

Space Weather Message Code: WARK04
Serial Number: 5354
Issue Time: 2026 May 29 0541 UTC

EXTENDED WARNING: Geomagnetic K-index of 4 expected
Extension to Serial Number: 5353
Valid From: 2026 May 27 2347 UTC
Now Valid Until: 2026 May 29 1200 UTC
Warning Condition: Persistence




NOAA Space Weather Scale descriptions can be found at
www.swpc.noaa.gov/noaa-scales-explanation

Potential Impacts: Area of impact primarily poleward of 65 degrees Geomagnetic Latitude.
Induced Currents - Weak power grid fluctuations can occur.
Aurora - Aurora may be visible at high latitudes such as Canada and Alaska.

00:11 UTC

Space Weather Message Code: WARK04
Serial Number: 5353
Issue Time: 2026 May 29 0011 UTC

EXTENDED WARNING: Geomagnetic K-index of 4 expected
Extension to Serial Number: 5352
Valid From: 2026 May 27 2347 UTC
Now Valid Until: 2026 May 29 0600 UTC
Warning Condition: Persistence




NOAA Space Weather Scale descriptions can be found at
www.swpc.noaa.gov/noaa-scales-explanation

Potential Impacts: Area of impact primarily poleward of 65 degrees Geomagnetic Latitude.
Induced Currents - Weak power grid fluctuations can occur.
Aurora - Aurora may be visible at high latitudes such as Canada and Alaska.

jeudi, 28 mai 2026

18:00 UTC

Space Weather Message Code: ALTK04
Serial Number: 2661
Issue Time: 2026 May 28 1800 UTC

ALERT: Geomagnetic K-index of 4
Threshold Reached: 2026 May 28 1800 UTC
Synoptic Period: 1800-2100
Active Warning: YES
Comment:



NOAA Space Weather Scale descriptions can be found at
www.swpc.noaa.gov/noaa-scales-explanation

Potential Impacts: Area of impact primarily poleward of 65 degrees Geomagnetic Latitude.
Induced Currents - Weak power grid fluctuations can occur.
Aurora - Aurora may be visible at high latitudes such as Canada and Alaska.

17:17 UTC

Space Weather Message Code: ALTK04
Serial Number: 2660
Issue Time: 2026 May 28 1717 UTC

CANCELLED ALERT: Geomagnetic K-index of 4
Cancel Serial Number: 2659
Original Issued Time: 2026-05-28T17:06:00
Cancelled 2026-05-28 17:17 by Forecaster User Incorrectly issued. Did not reach threshold.

Cancelled 2026-05-28 17:17 by Forecaster User Incorrectly issued. Did not reach threshold.

NOAA Space Weather Scale descriptions can be found at
www.swpc.noaa.gov/noaa-scales-explanation

Potential Impacts: Area of impact primarily poleward of 65 degrees Geomagnetic Latitude.
Induced Currents - Weak power grid fluctuations can occur.
Aurora - Aurora may be visible at high latitudes such as Canada and Alaska.

17:06 UTC

Space Weather Message Code: ALTK04
Serial Number: 2659
Issue Time: 2026 May 28 1706 UTC

ALERT: Geomagnetic K-index of 4
Threshold Reached: 2026 May 28 1706 UTC
Synoptic Period: 1500-1800
Active Warning: YES
Comment:



NOAA Space Weather Scale descriptions can be found at
www.swpc.noaa.gov/noaa-scales-explanation

Potential Impacts: Area of impact primarily poleward of 65 degrees Geomagnetic Latitude.
Induced Currents - Weak power grid fluctuations can occur.
Aurora - Aurora may be visible at high latitudes such as Canada and Alaska.

17:02 UTC

Space Weather Message Code: WARK04
Serial Number: 5352
Issue Time: 2026 May 28 1702 UTC

EXTENDED WARNING: Geomagnetic K-index of 4 expected
Extension to Serial Number: 5351
Valid From: 2026-05-27T23:47:00
Now Valid Until: 2026-05-29 03:00
Warning Condition: Persistence
Extended 2026-05-28 17:01 by Forecaster User

Extended 2026-05-28 17:01 by Forecaster User

NOAA Space Weather Scale descriptions can be found at
www.swpc.noaa.gov/noaa-scales-explanation

Potential Impacts: Area of impact primarily poleward of 65 degrees Geomagnetic Latitude.
Induced Currents - Weak power grid fluctuations can occur.
Aurora - Aurora may be visible at high latitudes such as Canada and Alaska.

11:45 UTC

Space Weather Message Code: WARK04
Serial Number: 5351
Issue Time: 2026 May 28 1145 UTC

EXTENDED WARNING: Geomagnetic K-index of 4 expected
Extension to Serial Number: 5350
Valid From: 2026-05-27T23:47:00
Now Valid Until: 2026-05-28 18:00
Warning Condition: Persistence
Extended 2026-05-28 11:44 by Forecaster User

Extended 2026-05-28 11:44 by Forecaster User

NOAA Space Weather Scale descriptions can be found at
www.swpc.noaa.gov/noaa-scales-explanation

Potential Impacts: Area of impact primarily poleward of 65 degrees Geomagnetic Latitude.
Induced Currents - Weak power grid fluctuations can occur.
Aurora - Aurora may be visible at high latitudes such as Canada and Alaska.

05:17 UTC

Space Weather Message Code: WARK04
Serial Number: 5350
Issue Time: 2026 May 28 0517 UTC

EXTENDED WARNING: Geomagnetic K-index of 4 expected
Extension to Serial Number: 5349
Valid From: 2026-05-27T23:47:00
Now Valid Until: 2026-05-28 12:00
Warning Condition: Persistence
Extended 2026-05-28 05:16 by Forecaster User

Extended 2026-05-28 05:16 by Forecaster User

NOAA Space Weather Scale descriptions can be found at
www.swpc.noaa.gov/noaa-scales-explanation

Potential Impacts: Area of impact primarily poleward of 65 degrees Geomagnetic Latitude.
Induced Currents - Weak power grid fluctuations can occur.
Aurora - Aurora may be visible at high latitudes such as Canada and Alaska.

mercredi, 27 mai 2026

23:47 UTC

Space Weather Message Code: WARK04
Serial Number: 5349
Issue Time: 2026 May 27 2347 UTC

WARNING: Geomagnetic K-index of 4 expected
Valid From: 2026 May 27 2347 UTC
Valid To: 2026 May 28 0600 UTC
Warning Conditions: Onset
Comment:



NOAA Space Weather Scale descriptions can be found at
www.swpc.noaa.gov/noaa-scales-explanation

Potential Impacts: Area of impact primarily poleward of 65 degrees Geomagnetic Latitude.
Induced Currents - Weak power grid fluctuations can occur.
Aurora - Aurora may be visible at high latitudes such as Canada and Alaska.

14:45 UTC

Space Weather Message Code: SUMPX1
Serial Number: 131
Issue Time: 2026 May 27 1445 UTC

CANCELLED SUMMARY: Proton Event 10MeV Integral Flux exceeded 10pfu
Cancel Serial Number: 130
Original Issued Time: 2026-05-27T02:28:00
Cancelled 2026-05-27 14:44 by Forecaster User duplicate

Cancelled 2026-05-27 14:44 by Forecaster User duplicateNOAA Scale: S1 - Minor

05:47 UTC

Space Weather Message Code: WARK04
Serial Number: 5348
Issue Time: 2026 May 27 0547 UTC

EXTENDED WARNING: Geomagnetic K-index of 4 expected
Extension to Serial Number: 5347
Valid From: 2026-05-26T21:37:00
Now Valid Until: 2026-05-27 12:00
Warning Condition: Persistence
Extended 2026-05-27 05:47 by Forecaster User

Extended 2026-05-27 05:47 by Forecaster User

NOAA Space Weather Scale descriptions can be found at
www.swpc.noaa.gov/noaa-scales-explanation

Potential Impacts: Area of impact primarily poleward of 65 degrees Geomagnetic Latitude.
Induced Currents - Weak power grid fluctuations can occur.
Aurora - Aurora may be visible at high latitudes such as Canada and Alaska.

02:28 UTC

Space Weather Message Code: SUMPX1
Serial Number: 130
Issue Time: 2026 May 27 0228 UTC

SUMMARY: Proton Event 10MeV Integral Flux exceeded 10pfu
Begin Time: 2026 May 27 0015 UTC
Maximum Time: 2026 May 26 0110 UTC
End Time: 2026 May 26 0425 UTC
Maximum 10MeV Flux: 23 pfu
Noaa Scale: S1 - Minor
Comment:

NOAA Scale: S1 - Minor

02:27 UTC

Space Weather Message Code: SUMPX1
Serial Number: 129
Issue Time: 2026 May 27 0227 UTC

SUMMARY: Proton Event 10MeV Integral Flux exceeded 10pfu
Begin Time: 2026 May 26 0015 UTC
Maximum Time: 2026 May 26 0110 UTC
End Time: 2026 May 26 0425 UTC
Maximum 10MeV Flux: 23 pfu
Noaa Scale: S1 - Minor
Comment:

NOAA Scale: S1 - Minor

00:01 UTC

Space Weather Message Code: ALTK04
Serial Number: 2658
Issue Time: 2026 May 27 0001 UTC

ALERT: Geomagnetic K-index of 4
Threshold Reached: 2026 May 26 2359 UTC
Synoptic Period: 2100-2400
Active Warning: YES
Comment:



NOAA Space Weather Scale descriptions can be found at
www.swpc.noaa.gov/noaa-scales-explanation

Potential Impacts: Area of impact primarily poleward of 65 degrees Geomagnetic Latitude.
Induced Currents - Weak power grid fluctuations can occur.
Aurora - Aurora may be visible at high latitudes such as Canada and Alaska.

mardi, 26 mai 2026

21:38 UTC

Space Weather Message Code: WARK04
Serial Number: 5347
Issue Time: 2026 May 26 2138 UTC

WARNING: Geomagnetic K-index of 4 expected
Valid From: 2026 May 26 2137 UTC
Valid To: 2026 May 27 0600 UTC
Warning Conditions: Onset
Comment:



NOAA Space Weather Scale descriptions can be found at
www.swpc.noaa.gov/noaa-scales-explanation

Potential Impacts: Area of impact primarily poleward of 65 degrees Geomagnetic Latitude.
Induced Currents - Weak power grid fluctuations can occur.
Aurora - Aurora may be visible at high latitudes such as Canada and Alaska.

14:22 UTC

Space Weather Message Code: ALTTP2
Serial Number: 1494
Issue Time: 2026 May 26 1422 UTC

ALERT: Type II Radio Emission
Begin Time: 2026 May 26 1244 UTC
Estimate Velocity: 650 km/s
Comment: SVI; updated with correct start time


SVI; updated with correct start time

14:20 UTC

Space Weather Message Code: ALTTP2
Serial Number: 1494
Issue Time: 2026 May 26 1420 UTC

ALERT: Type II Radio Emission
Begin Time: 2026 May 26 1420 UTC
Estimate Velocity: 650 km/s
Comment: SVI


SVI

14:19 UTC

Space Weather Message Code: ALTTP2
Serial Number: 1493
Issue Time: 2026 May 26 1419 UTC

CANCELLED ALERT: Type II Radio Emission
Cancel Serial Number: 1490
Original Issued Time: 2026-05-26T14:19:00
Cancelled 2026-05-26 14:19 by Forecaster User Duplicate.

Cancelled 2026-05-26 14:19 by Forecaster User Duplicate.

14:19 UTC

Space Weather Message Code: ALTTP2
Serial Number: 1492
Issue Time: 2026 May 26 1419 UTC

CANCELLED ALERT: Type II Radio Emission
Cancel Serial Number: 1491
Original Issued Time: 2026-05-26T14:19:00
Cancelled 2026-05-26 14:19 by Forecaster User Duplicate.

Cancelled 2026-05-26 14:19 by Forecaster User Duplicate.

14:19 UTC

Space Weather Message Code: ALTTP2
Serial Number: 1491
Issue Time: 2026 May 26 1419 UTC

ALERT: Type II Radio Emission
Begin Time: 2026 May 26 1244 UTC
Estimate Velocity: 650 km/s
Comment: SVI


SVI

14:19 UTC

Space Weather Message Code: ALTTP2
Serial Number: 1490
Issue Time: 2026 May 26 1419 UTC

ALERT: Type II Radio Emission
Begin Time: 2026 May 26 1244 UTC
Estimate Velocity: 650 km/s
Comment: SVI


SVI

14:19 UTC

Space Weather Message Code: ALTTP2
Serial Number: 1490
Issue Time: 2026 May 26 1418 UTC

ALERT: Type II Radio Emission
Begin Time: 2026 May 26 1244 UTC
Estimate Velocity: 650 km/s
Comment: SVI


SVI

14:19 UTC

Space Weather Message Code: ALTTP2
Serial Number: 1490
Issue Time: 2026 May 26 1419 UTC

ALERT: Type II Radio Emission
Begin Time: 2026 May 26 1244 UTC
Estimate Velocity: 650 km/s
Comment: SVI


SVI

14:19 UTC

Space Weather Message Code: ALTTP2
Serial Number: 1490
Issue Time: 2026 May 26 1419 UTC

ALERT: Type II Radio Emission
Begin Time: 2026 May 26 1244 UTC
Estimate Velocity: 650 km/s
Comment: SVI


SVI

14:19 UTC

Space Weather Message Code: ALTTP2
Serial Number: 1490
Issue Time: 2026 May 26 1419 UTC

ALERT: Type II Radio Emission
Begin Time: 2026 May 26 1244 UTC
Estimate Velocity: 650 km/s
Comment: SVI


SVI

14:19 UTC

Space Weather Message Code: ALTTP2
Serial Number: 1490
Issue Time: 2026 May 26 1419 UTC

ALERT: Type II Radio Emission
Begin Time: 2026 May 26 1244 UTC
Estimate Velocity: 650 km/s
Comment: SVI


SVI

00:35 UTC

Space Weather Message Code: ALTPX1
Serial Number: 365
Issue Time: 2026 May 26 0035 UTC

ALERT: Proton Event 10meV Integral Flux exceeded 10pfu
Begin Time: 2026 May 26 0010 UTC
Noaa Scale: S1 - Minor
Comment:

NOAA Scale: S1 - Minor

00:16 UTC

Space Weather Message Code: WARPX1
Serial Number: 625
Issue Time: 2026 May 26 0016 UTC

WARNING: Proton 10MeV Integral Flux above 10pfu expected
Valid From: 2026 May 26 0015 UTC
Valid To: 2026 May 26 2359 UTC
Warning Conditions: Onset
Noaa Scale: S1 - Minor
Comment:

NOAA Scale: S1 - Minor

dimanche, 24 mai 2026

12:11 UTC

Space Weather Message Code: ALTTP2
Serial Number: 1489
Issue Time: 2026 May 24 1211 UTC

ALERT: Type II Radio Emission
Begin Time: 2026 May 24 0850 UTC
Estimate Velocity: 579 km/s
Comment:

05:00 UTC

Space Weather Message Code: ALTEF3
Serial Number: 3694
Issue Time: 2026 May 24 0500 UTC

CONTINUED ALERT: Electron 2MeV Integral Flux exceeded 1000pfu
Continuation of Serial Number: 3693
Begin Time: 2026-05-16 17:40
Yesterday Maximum 2MeV Flux: 3762 pfu
Continued 2026-05-24 04:59 by Forecaster User

Continued 2026-05-24 04:59 by Forecaster User

samedi, 23 mai 2026

20:00 UTC

Space Weather Message Code: ALTTP2
Serial Number: 1488
Issue Time: 2026 May 23 2000 UTC

ALERT: Type II Radio Emission
Begin Time: 2026 May 23 1941 UTC
Estimate Velocity: 932 km/s
Comment:

06:31 UTC

Space Weather Message Code: ALTEF3
Serial Number: 3693
Issue Time: 2026 May 23 0631 UTC

CONTINUED ALERT: Electron 2MeV Integral Flux exceeded 1000pfu
Continuation of Serial Number: 3692
Begin Time: 2026-05-16 17:40
Yesterday Maximum 2MeV Flux: 3762 pfu
Continued 2026-05-23 06:31 by Forecaster User

Continued 2026-05-23 06:31 by Forecaster User

vendredi, 22 mai 2026

05:07 UTC

Space Weather Message Code: ALTEF3
Serial Number: 3692
Issue Time: 2026 May 22 0507 UTC

CONTINUED ALERT: Electron 2MeV Integral Flux exceeded 1000pfu
Continuation of Serial Number: 3691
Begin Time: 2026-05-16 17:40
Yesterday Maximum 2MeV Flux: 2842 pfu
Continued 2026-05-22 05:06 by Forecaster User

Continued 2026-05-22 05:06 by Forecaster User

jeudi, 21 mai 2026

05:09 UTC

Space Weather Message Code: ALTEF3
Serial Number: 3691
Issue Time: 2026 May 21 0509 UTC

CONTINUED ALERT: Electron 2MeV Integral Flux exceeded 1000pfu
Continuation of Serial Number: 3690
Begin Time: 2026-05-16 17:40
Yesterday Maximum 2MeV Flux: 1717 pfu
Continued 2026-05-21 05:07 by Forecaster User

Continued 2026-05-21 05:07 by Forecaster User

mercredi, 20 mai 2026

10:06 UTC

Space Weather Message Code: ALTEF3
Serial Number: 3690
Issue Time: 2026 May 20 1006 UTC

CONTINUED ALERT: Electron 2MeV Integral Flux exceeded 1000pfu
Continuation of Serial Number: 3689
Begin Time: 2026-05-16 17:40
Yesterday Maximum 2MeV Flux: 2860 pfu
Continued 2026-05-20 10:06 by Forecaster User

Continued 2026-05-20 10:06 by Forecaster User

mardi, 19 mai 2026

23:56 UTC

Space Weather Message Code: WARK04
Serial Number: 5346
Issue Time: 2026 May 19 2356 UTC

EXTENDED WARNING: Geomagnetic K-index of 4 expected
Extension to Serial Number: 5345
Valid From: 2026-05-19T07:01:00
Now Valid Until: 2026-05-20 06:00
Warning Condition: Persistence
Extended 2026-05-19 23:56 by Forecaster User

Extended 2026-05-19 23:56 by Forecaster User

NOAA Space Weather Scale descriptions can be found at
www.swpc.noaa.gov/noaa-scales-explanation

Potential Impacts: Area of impact primarily poleward of 65 degrees Geomagnetic Latitude.
Induced Currents - Weak power grid fluctuations can occur.
Aurora - Aurora may be visible at high latitudes such as Canada and Alaska.

20:57 UTC

Space Weather Message Code: WARK04
Serial Number: 5345
Issue Time: 2026 May 19 2057 UTC

EXTENDED WARNING: Geomagnetic K-index of 4 expected
Extension to Serial Number: 5344
Valid From: 2026-05-19T07:01:00
Now Valid Until: 2026-05-19 24:00
Warning Condition: Persistence
Extended 2026-05-19 20:57 by Forecaster User

Extended 2026-05-19 20:57 by Forecaster User

NOAA Space Weather Scale descriptions can be found at
www.swpc.noaa.gov/noaa-scales-explanation

Potential Impacts: Area of impact primarily poleward of 65 degrees Geomagnetic Latitude.
Induced Currents - Weak power grid fluctuations can occur.
Aurora - Aurora may be visible at high latitudes such as Canada and Alaska.

16:42 UTC

Space Weather Message Code: WARK04
Serial Number: 5344
Issue Time: 2026 May 19 1642 UTC

EXTENDED WARNING: Geomagnetic K-index of 4 expected
Extension to Serial Number: 5343
Valid From: 2026-05-19T07:01:00
Now Valid Until: 2026-05-19 21:00
Warning Condition: Persistence
Extended 2026-05-19 16:41 by Forecaster User

Extended 2026-05-19 16:41 by Forecaster User

NOAA Space Weather Scale descriptions can be found at
www.swpc.noaa.gov/noaa-scales-explanation

Potential Impacts: Area of impact primarily poleward of 65 degrees Geomagnetic Latitude.
Induced Currents - Weak power grid fluctuations can occur.
Aurora - Aurora may be visible at high latitudes such as Canada and Alaska.

08:55 UTC

Space Weather Message Code: ALTK04
Serial Number: 2657
Issue Time: 2026 May 19 0855 UTC

ALERT: Geomagnetic K-index of 4
Threshold Reached: 2026 May 19 0828 UTC
Synoptic Period: 0600-0900
Active Warning: YES
Comment:



NOAA Space Weather Scale descriptions can be found at
www.swpc.noaa.gov/noaa-scales-explanation

Potential Impacts: Area of impact primarily poleward of 65 degrees Geomagnetic Latitude.
Induced Currents - Weak power grid fluctuations can occur.
Aurora - Aurora may be visible at high latitudes such as Canada and Alaska.

07:03 UTC

Space Weather Message Code: WARK04
Serial Number: 5343
Issue Time: 2026 May 19 0703 UTC

WARNING: Geomagnetic K-index of 4 expected
Valid From: 2026 May 19 0701 UTC
Valid To: 2026 May 19 1800 UTC
Warning Conditions: Onset
Comment:



NOAA Space Weather Scale descriptions can be found at
www.swpc.noaa.gov/noaa-scales-explanation

Potential Impacts: Area of impact primarily poleward of 65 degrees Geomagnetic Latitude.
Induced Currents - Weak power grid fluctuations can occur.
Aurora - Aurora may be visible at high latitudes such as Canada and Alaska.

05:14 UTC

Space Weather Message Code: ALTEF3
Serial Number: 3689
Issue Time: 2026 May 19 0514 UTC

ALERT: Electron 2MeV Integral Flux exceeded 1000pfu
Threshold Reached: 2026 May 16 1740 UTC
Station: GOES-19
Comment: Yesterday's max: 6667 pfu


Yesterday's max: 6667 pfu

04:56 UTC

Space Weather Message Code: ALTEF3
Serial Number: 3689
Issue Time: 2026 May 19 0456 UTC

CONTINUED ALERT: Electron 2MeV Integral Flux exceeded 1000pfu
Continuation of Serial Number: 3688
Begin Time: 2026-05-16 17:40
Yesterday Maximum 2MeV Flux: 6118 pfu
Continued 2026-05-19 05:00 by Forecaster User

Continued 2026-05-19 05:00 by Forecaster User

lundi, 18 mai 2026

05:00 UTC

Space Weather Message Code: ALTEF3
Serial Number: 3688
Issue Time: 2026 May 18 0500 UTC

CONTINUED ALERT: Electron 2MeV Integral Flux exceeded 1000pfu
Continuation of Serial Number: 3687
Begin Time: 2026-05-16 17:40
Yesterday Maximum 2MeV Flux: 6118 pfu
Continued 2026-05-18 04:59 by Forecaster User

Continued 2026-05-18 04:59 by Forecaster User

dimanche, 17 mai 2026

21:16 UTC

Space Weather Message Code: SUM10R
Serial Number: 913
Issue Time: 2026 May 17 2116 UTC

SUMMARY: 10cm Radio Burst
Begin Time: 2026 May 17 2050 UTC
Maximum Time: 2026 May 17 2051 UTC
End Time: 2026 May 17 2051 UTC
Peak Flux: 370 sfu
Duration: 1 minutes
Latest Penticton Noon Flux: 104 sfu
Comment:

16:12 UTC

Space Weather Message Code: WATA20
Serial Number: 1113
Issue Time: 2026 May 17 1612 UTC

WATCH: Geomagnetic Storm Category G1 Predicted
Highest Storm Level Predicted by Day:
May 18: G1 (Minor) May 19: G1 (Minor) May 20: None (Below G1)
THIS SUPERSEDES ANY/ALL PRIOR WATCHES IN EFFECT
Comment:



NOAA Space Weather Scale descriptions can be found at
www.swpc.noaa.gov/noaa-scales-explanation

Potential Impacts: Area of impact primarily poleward of 60 degrees Geomagnetic Latitude.
Induced Currents - Weak power grid fluctuations can occur.
Spacecraft - Minor impact on satellite operations possible.
Aurora - Aurora may be visible at high latitudes, i.e., northern tier of the U.S. such as northern Michigan and Maine.

08:40 UTC

Space Weather Message Code: WARK04
Serial Number: 5342
Issue Time: 2026 May 17 0840 UTC

EXTENDED WARNING: Geomagnetic K-index of 4 expected
Extension to Serial Number: 5341
Valid From: 2026-05-13T20:26:00
Now Valid Until: 2026-05-17 21:00
Warning Condition: Persistence
Extended 2026-05-17 08:38 by Forecaster User

Extended 2026-05-17 08:38 by Forecaster User

NOAA Space Weather Scale descriptions can be found at
www.swpc.noaa.gov/noaa-scales-explanation

Potential Impacts: Area of impact primarily poleward of 65 degrees Geomagnetic Latitude.
Induced Currents - Weak power grid fluctuations can occur.
Aurora - Aurora may be visible at high latitudes such as Canada and Alaska.

08:16 UTC

Space Weather Message Code: ALTEF3
Serial Number: 3687
Issue Time: 2026 May 17 0816 UTC

CONTINUED ALERT: Electron 2MeV Integral Flux exceeded 1000pfu
Continuation of Serial Number: 3686
Begin Time: 2026-05-16 17:40
Yesterday Maximum 2MeV Flux: 1902 pfu
Continued 2026-05-17 08:16 by Forecaster User

Continued 2026-05-17 08:16 by Forecaster User

samedi, 16 mai 2026

21:34 UTC

Space Weather Message Code: WATA20
Serial Number: 1112
Issue Time: 2026 May 16 2134 UTC

WATCH: Geomagnetic Storm Category G1 Predicted
Highest Storm Level Predicted by Day:
May 17: G1 (Minor) May 18: G1 (Minor) May 19: None (Below G1)
THIS SUPERSEDES ANY/ALL PRIOR WATCHES IN EFFECT
Comment:



NOAA Space Weather Scale descriptions can be found at
www.swpc.noaa.gov/noaa-scales-explanation

Potential Impacts: Area of impact primarily poleward of 60 degrees Geomagnetic Latitude.
Induced Currents - Weak power grid fluctuations can occur.
Spacecraft - Minor impact on satellite operations possible.
Aurora - Aurora may be visible at high latitudes, i.e., northern tier of the U.S. such as northern Michigan and Maine.

18:14 UTC

Space Weather Message Code: WARK05
Serial Number: 2237
Issue Time: 2026 May 16 1814 UTC

EXTENDED WARNING: Geomagnetic K-index of 5 expected
Extension to Serial Number: 2236
Valid From: 2026-05-15T13:05:00
Now Valid Until: 2026-05-17 09:00
Warning Condition: Persistence
Extended 2026-05-16 18:13 by WC

Extended 2026-05-16 18:13 by WC NOAA Scale: G1 - Minor

NOAA Space Weather Scale descriptions can be found at
www.swpc.noaa.gov/noaa-scales-explanation

Potential Impacts: Area of impact primarily poleward of 60 degrees Geomagnetic Latitude.
Induced Currents - Weak power grid fluctuations can occur.
Spacecraft - Minor impact on satellite operations possible.
Aurora - Aurora may be visible at high latitudes, i.e., northern tier of the U.S. such as northern Michigan and Maine.

18:13 UTC

Space Weather Message Code: WARK04
Serial Number: 5341
Issue Time: 2026 May 16 1813 UTC

EXTENDED WARNING: Geomagnetic K-index of 4 expected
Extension to Serial Number: 5340
Valid From: 2026-05-13T20:26:00
Now Valid Until: 2026-05-17 09:00
Warning Condition: Persistence
Extended 2026-05-16 18:12 by WC

Extended 2026-05-16 18:12 by WC

NOAA Space Weather Scale descriptions can be found at
www.swpc.noaa.gov/noaa-scales-explanation

Potential Impacts: Area of impact primarily poleward of 65 degrees Geomagnetic Latitude.
Induced Currents - Weak power grid fluctuations can occur.
Aurora - Aurora may be visible at high latitudes such as Canada and Alaska.

18:04 UTC

Space Weather Message Code: ALTK05
Serial Number: 2022
Issue Time: 2026 May 16 1804 UTC

ALERT: Geomagnetic K-index of 5
Threshold Reached: 2026 May 16 1759 UTC
Synoptic Period: 1500-1800
Active Warning: YES
Noaa Scale: G1 - Minor
Comment:

NOAA Scale: G1 - Minor

NOAA Space Weather Scale descriptions can be found at
www.swpc.noaa.gov/noaa-scales-explanation

Potential Impacts: Area of impact primarily poleward of 60 degrees Geomagnetic Latitude.
Induced Currents - Weak power grid fluctuations can occur.
Spacecraft - Minor impact on satellite operations possible.
Aurora - Aurora may be visible at high latitudes, i.e., northern tier of the U.S. such as northern Michigan and Maine.

17:53 UTC

Space Weather Message Code: ALTEF3
Serial Number: 3686
Issue Time: 2026 May 16 1753 UTC

ALERT: Electron 2MeV Integral Flux exceeded 1000pfu
Threshold Reached: 2026 May 16 1740 UTC
Station: GOES-19
Comment:

16:58 UTC

Space Weather Message Code: ALTTP4
Serial Number: 709
Issue Time: 2026 May 16 1658 UTC

ALERT: Type IV Radio Emission
Begin Time: 2026 May 16 1605 UTC
Comment:

16:37 UTC

Space Weather Message Code: SUM10R
Serial Number: 912
Issue Time: 2026 May 16 1637 UTC

SUMMARY: 10cm Radio Burst
Begin Time: 2026 May 16 1606 UTC
Maximum Time: 2026 May 16 1609 UTC
End Time: 2026 May 16 1610 UTC
Peak Flux: 170 sfu
Duration: 4 minutes
Latest Penticton Noon Flux: 101 sfu
Comment: COR for end date.


COR for end date.

16:31 UTC

Space Weather Message Code: SUM10R
Serial Number: 912
Issue Time: 2026 May 16 1631 UTC

SUMMARY: 10cm Radio Burst
Begin Time: 2026 May 16 1606 UTC
Maximum Time: 2026 May 16 1609 UTC
End Time: 2026 May 17 1610 UTC
Peak Flux: 170 sfu
Duration: 4 minutes
Latest Penticton Noon Flux: 101 sfu
Comment:

11:56 UTC

Space Weather Message Code: WARK04
Serial Number: 5340
Issue Time: 2026 May 16 1156 UTC

EXTENDED WARNING: Geomagnetic K-index of 4 expected
Extension to Serial Number: 5339
Valid From: 2026-05-13T20:26:00
Now Valid Until: 2026-05-16 23:59
Warning Condition: Persistence
Extended 2026-05-16 11:55 by Forecaster User

Extended 2026-05-16 11:55 by Forecaster User

NOAA Space Weather Scale descriptions can be found at
www.swpc.noaa.gov/noaa-scales-explanation

Potential Impacts: Area of impact primarily poleward of 65 degrees Geomagnetic Latitude.
Induced Currents - Weak power grid fluctuations can occur.
Aurora - Aurora may be visible at high latitudes such as Canada and Alaska.

08:59 UTC

Space Weather Message Code: ALTK05
Serial Number: 2021
Issue Time: 2026 May 16 0859 UTC

ALERT: Geomagnetic K-index of 5
Threshold Reached: 2026 May 16 0859 UTC
Synoptic Period: 0600-0900
Active Warning: YES
Noaa Scale: G1 - Minor
Comment:

NOAA Scale: G1 - Minor

NOAA Space Weather Scale descriptions can be found at
www.swpc.noaa.gov/noaa-scales-explanation

Potential Impacts: Area of impact primarily poleward of 60 degrees Geomagnetic Latitude.
Induced Currents - Weak power grid fluctuations can occur.
Spacecraft - Minor impact on satellite operations possible.
Aurora - Aurora may be visible at high latitudes, i.e., northern tier of the U.S. such as northern Michigan and Maine.

08:45 UTC

Space Weather Message Code: WARK05
Serial Number: 2236
Issue Time: 2026 May 16 0845 UTC

EXTENDED WARNING: Geomagnetic K-index of 5 expected
Extension to Serial Number: 2235
Valid From: 2026-05-15T13:05:00
Now Valid Until: 2026-05-16 21:00
Warning Condition: Persistence
Extended 2026-05-16 08:44 by Forecaster User

Extended 2026-05-16 08:44 by Forecaster User NOAA Scale: G1 - Minor

NOAA Space Weather Scale descriptions can be found at
www.swpc.noaa.gov/noaa-scales-explanation

Potential Impacts: Area of impact primarily poleward of 60 degrees Geomagnetic Latitude.
Induced Currents - Weak power grid fluctuations can occur.
Spacecraft - Minor impact on satellite operations possible.
Aurora - Aurora may be visible at high latitudes, i.e., northern tier of the U.S. such as northern Michigan and Maine.

05:56 UTC

Space Weather Message Code: ALTK05
Serial Number: 2020
Issue Time: 2026 May 16 0556 UTC

ALERT: Geomagnetic K-index of 5
Threshold Reached: 2026 May 16 0554 UTC
Synoptic Period: 0300-0600
Active Warning: YES
Noaa Scale: G1 - Minor
Comment:

NOAA Scale: G1 - Minor

NOAA Space Weather Scale descriptions can be found at
www.swpc.noaa.gov/noaa-scales-explanation

Potential Impacts: Area of impact primarily poleward of 60 degrees Geomagnetic Latitude.
Induced Currents - Weak power grid fluctuations can occur.
Spacecraft - Minor impact on satellite operations possible.
Aurora - Aurora may be visible at high latitudes, i.e., northern tier of the U.S. such as northern Michigan and Maine.

vendredi, 15 mai 2026

23:56 UTC

Space Weather Message Code: WARK05
Serial Number: 2235
Issue Time: 2026 May 15 2356 UTC

EXTENDED WARNING: Geomagnetic K-index of 5 expected
Extension to Serial Number: 2234
Valid From: 2026-05-15T13:05:00
Now Valid Until: 2026-05-16 09:00
Warning Condition: Persistence
Extended 2026-05-15 23:55 by Forecaster User

Extended 2026-05-15 23:55 by Forecaster User NOAA Scale: G1 - Minor

NOAA Space Weather Scale descriptions can be found at
www.swpc.noaa.gov/noaa-scales-explanation

Potential Impacts: Area of impact primarily poleward of 60 degrees Geomagnetic Latitude.
Induced Currents - Weak power grid fluctuations can occur.
Spacecraft - Minor impact on satellite operations possible.
Aurora - Aurora may be visible at high latitudes, i.e., northern tier of the U.S. such as northern Michigan and Maine.

22:15 UTC

Space Weather Message Code: ALTK06
Serial Number: 717
Issue Time: 2026 May 15 2215 UTC

ALERT: Geomagnetic K-index of 6
Threshold Reached: 2026 May 15 2215 UTC
Synoptic Period: 2100-2400
Active Warning: YES
Noaa Scale: G2 - Moderate
Comment:

NOAA Scale: G2 - Moderate

NOAA Space Weather Scale descriptions can be found at
www.swpc.noaa.gov/noaa-scales-explanation

Potential Impacts: Area of impact primarily poleward of 55 degrees Geomagnetic Latitude.
Induced Currents - Power grid fluctuations can occur. High-latitude power systems may experience voltage alarms.
Spacecraft - Satellite orientation irregularities may occur; increased drag on low Earth-orbit satellites is possible.
Radio - HF (high frequency) radio propagation can fade at higher latitudes.
Aurora - Aurora may be seen as low as New York to Wisconsin to Washington state.

22:02 UTC

Space Weather Message Code: WARK06
Serial Number: 660
Issue Time: 2026 May 15 2202 UTC

WARNING: Geomagnetic K-index of 6 expected
Valid From: 2026 May 15 2201 UTC
Valid To: 2026 May 16 0300 UTC
Warning Conditions: Onset
Noaa Scale: G2 - Moderate
Comment:

NOAA Scale: G2 - Moderate

NOAA Space Weather Scale descriptions can be found at
www.swpc.noaa.gov/noaa-scales-explanation

Potential Impacts: Area of impact primarily poleward of 55 degrees Geomagnetic Latitude.
Induced Currents - Power grid fluctuations can occur. High-latitude power systems may experience voltage alarms.
Spacecraft - Satellite orientation irregularities may occur; increased drag on low Earth-orbit satellites is possible.
Radio - HF (high frequency) radio propagation can fade at higher latitudes.
Aurora - Aurora may be seen as low as New York to Wisconsin to Washington state.

17:18 UTC

Space Weather Message Code: ALTTP2
Serial Number: 1487
Issue Time: 2026 May 15 1718 UTC

ALERT: Type II Radio Emission
Begin Time: 2026 May 15 1616 UTC
Estimate Velocity: 529 km/s
Comment:

16:07 UTC

Space Weather Message Code: ALTK05
Serial Number: 2019
Issue Time: 2026 May 15 1607 UTC

ALERT: Geomagnetic K-index of 5
Threshold Reached: 2026 May 15 1606 UTC
Synoptic Period: 1500-1800
Active Warning: YES
Noaa Scale: G1 - Minor
Comment:

NOAA Scale: G1 - Minor

NOAA Space Weather Scale descriptions can be found at
www.swpc.noaa.gov/noaa-scales-explanation

Potential Impacts: Area of impact primarily poleward of 60 degrees Geomagnetic Latitude.
Induced Currents - Weak power grid fluctuations can occur.
Spacecraft - Minor impact on satellite operations possible.
Aurora - Aurora may be visible at high latitudes, i.e., northern tier of the U.S. such as northern Michigan and Maine.

14:50 UTC

Space Weather Message Code: WARK06
Serial Number: 659
Issue Time: 2026 May 15 1450 UTC

WARNING: Geomagnetic K-index of 6 expected
Valid From: 2026 May 15 1449 UTC
Valid To: 2026 May 15 2100 UTC
Warning Conditions: Onset
Noaa Scale: G2 - Moderate
Comment:

NOAA Scale: G2 - Moderate

NOAA Space Weather Scale descriptions can be found at
www.swpc.noaa.gov/noaa-scales-explanation

Potential Impacts: Area of impact primarily poleward of 55 degrees Geomagnetic Latitude.
Induced Currents - Power grid fluctuations can occur. High-latitude power systems may experience voltage alarms.
Spacecraft - Satellite orientation irregularities may occur; increased drag on low Earth-orbit satellites is possible.
Radio - HF (high frequency) radio propagation can fade at higher latitudes.
Aurora - Aurora may be seen as low as New York to Wisconsin to Washington state.

13:45 UTC

Space Weather Message Code: ALTTP2
Serial Number: 1486
Issue Time: 2026 May 15 1345 UTC

ALERT: Type II Radio Emission
Begin Time: 2026 May 15 1344 UTC
Estimate Velocity: 347 km/s
Comment:

13:27 UTC

Space Weather Message Code: ALTK05
Serial Number: 2018
Issue Time: 2026 May 15 1327 UTC

ALERT: Geomagnetic K-index of 5
Threshold Reached: 2026 May 15 1326 UTC
Synoptic Period: 1200-1500
Active Warning: YES
Noaa Scale: G1 - Minor
Comment:

NOAA Scale: G1 - Minor

NOAA Space Weather Scale descriptions can be found at
www.swpc.noaa.gov/noaa-scales-explanation

Potential Impacts: Area of impact primarily poleward of 60 degrees Geomagnetic Latitude.
Induced Currents - Weak power grid fluctuations can occur.
Spacecraft - Minor impact on satellite operations possible.
Aurora - Aurora may be visible at high latitudes, i.e., northern tier of the U.S. such as northern Michigan and Maine.

13:12 UTC

Space Weather Message Code: WARK05
Serial Number: 2234
Issue Time: 2026 May 15 1307 UTC

WARNING: Geomagnetic K-index of 5 expected
Valid From: 2026 May 15 1305 UTC
Valid To: 2026 May 15 2359 UTC
Warning Conditions: Onset
Noaa Scale: G1 - Minor
Comment:

NOAA Scale: G1 - Minor

NOAA Space Weather Scale descriptions can be found at
www.swpc.noaa.gov/noaa-scales-explanation

Potential Impacts: Area of impact primarily poleward of 60 degrees Geomagnetic Latitude.
Induced Currents - Weak power grid fluctuations can occur.
Spacecraft - Minor impact on satellite operations possible.
Aurora - Aurora may be visible at high latitudes, i.e., northern tier of the U.S. such as northern Michigan and Maine.

13:09 UTC

Space Weather Message Code: WARK04
Serial Number: 5339
Issue Time: 2026 May 15 1309 UTC

EXTENDED WARNING: Geomagnetic K-index of 4 expected
Extension to Serial Number: 5337
Valid From: 2026-05-13T20:26:00
Now Valid Until: 2026-05-16 12:00
Warning Condition: Persistence
Extended 2026-05-15 13:09 by Forecaster User

Extended 2026-05-15 13:09 by Forecaster User

NOAA Space Weather Scale descriptions can be found at
www.swpc.noaa.gov/noaa-scales-explanation

Potential Impacts: Area of impact primarily poleward of 65 degrees Geomagnetic Latitude.
Induced Currents - Weak power grid fluctuations can occur.
Aurora - Aurora may be visible at high latitudes such as Canada and Alaska.

13:00 UTC

Space Weather Message Code: ALTK04
Serial Number: 2656
Issue Time: 2026 May 15 1300 UTC

ALERT: Geomagnetic K-index of 4
Threshold Reached: 2026 May 15 1300 UTC
Synoptic Period: 1200-1500
Active Warning: YES
Comment:



NOAA Space Weather Scale descriptions can be found at
www.swpc.noaa.gov/noaa-scales-explanation

Potential Impacts: Area of impact primarily poleward of 65 degrees Geomagnetic Latitude.
Induced Currents - Weak power grid fluctuations can occur.
Aurora - Aurora may be visible at high latitudes such as Canada and Alaska.

12:25 UTC

Space Weather Message Code: ALTTP2
Serial Number: 1485
Issue Time: 2026 May 15 1225 UTC

ALERT: Type II Radio Emission
Begin Time: 2026 May 15 1225 UTC
Estimate Velocity: 486 km/s
Comment:

11:58 UTC

Space Weather Message Code: WARK04
Serial Number: 5338
Issue Time: 2026 May 15 1158 UTC

WARNING: Geomagnetic K-index of 4 expected
Valid From: 2026 May 15 1157 UTC
Valid To: 2026 May 16 0000 UTC
Warning Conditions: Onset
Comment:



NOAA Space Weather Scale descriptions can be found at
www.swpc.noaa.gov/noaa-scales-explanation

Potential Impacts: Area of impact primarily poleward of 65 degrees Geomagnetic Latitude.
Induced Currents - Weak power grid fluctuations can occur.
Aurora - Aurora may be visible at high latitudes such as Canada and Alaska.

jeudi, 14 mai 2026

08:53 UTC

Space Weather Message Code: WATA30
Serial Number: 273
Issue Time: 2026 May 14 0853 UTC

WATCH: Geomagnetic Storm Category G2 Predicted
Highest Storm Level Predicted by Day:
May 15: G2 (Moderate) May 16: G1 (Minor) May 17: G1 (Minor)
THIS SUPERSEDES ANY/ALL PRIOR WATCHES IN EFFECT
Comment: included the G1 watch for day3 (17 May)


included the G1 watch for day3 (17 May)

NOAA Space Weather Scale descriptions can be found at
www.swpc.noaa.gov/noaa-scales-explanation

Potential Impacts: Area of impact primarily poleward of 55 degrees Geomagnetic Latitude.
Induced Currents - Power grid fluctuations can occur. High-latitude power systems may experience voltage alarms.
Spacecraft - Satellite orientation irregularities may occur; increased drag on low Earth-orbit satellites is possible.
Radio - HF (high frequency) radio propagation can fade at higher latitudes.
Aurora - Aurora may be seen as low as New York to Wisconsin to Washington state.

mercredi, 13 mai 2026

20:27 UTC

Space Weather Message Code: WARK04
Serial Number: 5337
Issue Time: 2026 May 13 2027 UTC

WARNING: Geomagnetic K-index of 4 expected
Valid From: 2026 May 13 2026 UTC
Valid To: 2026 May 14 0600 UTC
Warning Conditions: Onset
Comment:



NOAA Space Weather Scale descriptions can be found at
www.swpc.noaa.gov/noaa-scales-explanation

Potential Impacts: Area of impact primarily poleward of 65 degrees Geomagnetic Latitude.
Induced Currents - Weak power grid fluctuations can occur.
Aurora - Aurora may be visible at high latitudes such as Canada and Alaska.

09:07 UTC

Space Weather Message Code: WATA30
Serial Number: 273
Issue Time: 2026 May 13 0907 UTC

WATCH: Geomagnetic Storm Category G2 Predicted
Highest Storm Level Predicted by Day:
May 14: None (Below G1) May 15: G2 (Moderate) May 16: G1 (Minor)
THIS SUPERSEDES ANY/ALL PRIOR WATCHES IN EFFECT
Comment:



NOAA Space Weather Scale descriptions can be found at
www.swpc.noaa.gov/noaa-scales-explanation

Potential Impacts: Area of impact primarily poleward of 55 degrees Geomagnetic Latitude.
Induced Currents - Power grid fluctuations can occur. High-latitude power systems may experience voltage alarms.
Spacecraft - Satellite orientation irregularities may occur; increased drag on low Earth-orbit satellites is possible.
Radio - HF (high frequency) radio propagation can fade at higher latitudes.
Aurora - Aurora may be seen as low as New York to Wisconsin to Washington state.

mardi, 12 mai 2026

13:26 UTC

Space Weather Message Code: WATA20
Serial Number: 1111
Issue Time: 2026 May 12 1326 UTC

WATCH: Geomagnetic Storm Category G1 Predicted
Highest Storm Level Predicted by Day:
May 13: None (Below G1) May 14: None (Below G1) May 15: G1 (Minor)
THIS SUPERSEDES ANY/ALL PRIOR WATCHES IN EFFECT
Comment: Negative CH influence


Negative CH influence

NOAA Space Weather Scale descriptions can be found at
www.swpc.noaa.gov/noaa-scales-explanation

Potential Impacts: Area of impact primarily poleward of 60 degrees Geomagnetic Latitude.
Induced Currents - Weak power grid fluctuations can occur.
Spacecraft - Minor impact on satellite operations possible.
Aurora - Aurora may be visible at high latitudes, i.e., northern tier of the U.S. such as northern Michigan and Maine.

dimanche, 10 mai 2026

14:14 UTC

Space Weather Message Code: SUMXM5
Serial Number: 316
Issue Time: 2026 May 10 1414 UTC

SUMMARY: X-ray Event exceeded M5
Begin Time: 2026 May 10 1319 UTC
Maximum Time: 2026 May 10 1339 UTC
End Time: 2026 May 10 1402 UTC
Xray Class: M5.7
Optical Class:
Location: N18E65
Noaa Scale: R2 - Moderate
Comment:

NOAA Scale: R2 - Moderate

NOAA Space Weather Scale descriptions can be found at
www.swpc.noaa.gov/noaa-scales-explanation

Potential Impacts: Area of impact centered primarily on sub-solar point on the sunlit side of Earth.
Radio - Limited blackout of HF (high frequency) radio communication for tens of minutes.

13:55 UTC

Space Weather Message Code: SUM10R
Serial Number: 911
Issue Time: 2026 May 10 1355 UTC

SUMMARY: 10cm Radio Burst
Begin Time: 2026 May 10 1328 UTC
Maximum Time: 2026 May 10 1334 UTC
End Time: 2026 May 10 1343 UTC
Peak Flux: 550 sfu
Duration: 15 minutes
Latest Penticton Noon Flux: 122 sfu
Comment:

13:47 UTC

Space Weather Message Code: ALTTP2
Serial Number: 1484
Issue Time: 2026 May 10 1347 UTC

ALERT: Type II Radio Emission
Begin Time: 2026 May 10 1329 UTC
Estimate Velocity: 650 km/s
Comment:

13:38 UTC

Space Weather Message Code: ALTXMF
Serial Number: 528
Issue Time: 2026 May 10 1338 UTC

ALERT: X-Ray Flux exceeded M5
Threshold Reached: 2026 May 10 1335 UTC
Noaa Scale: R2 - Moderate
Comment:

NOAA Scale: R2 - Moderate

NOAA Space Weather Scale descriptions can be found at
www.swpc.noaa.gov/noaa-scales-explanation

Potential Impacts: Area of impact centered on sub-solar point on the sunlit side of Earth. Extent of blackout of HF (high frequency) radio communication dependent upon current X-ray Flux intensity. For real-time information on affected area and expected duration please see http://www.swpc.noaa.gov/products/d-region-absorption-predictions-d-rap.

vendredi, 8 mai 2026

17:25 UTC

Space Weather Message Code: WARK04
Serial Number: 5336
Issue Time: 2026 May 08 1725 UTC

WARNING: Geomagnetic K-index of 4 expected
Valid From: 2026 May 08 1724 UTC
Valid To: 2026 May 08 2359 UTC
Warning Conditions: Onset
Comment:



NOAA Space Weather Scale descriptions can be found at
www.swpc.noaa.gov/noaa-scales-explanation

Potential Impacts: Area of impact primarily poleward of 65 degrees Geomagnetic Latitude.
Induced Currents - Weak power grid fluctuations can occur.
Aurora - Aurora may be visible at high latitudes such as Canada and Alaska.

jeudi, 7 mai 2026

16:37 UTC

Space Weather Message Code: WARK04
Serial Number: 5335
Issue Time: 2026 May 07 1637 UTC

WARNING: Geomagnetic K-index of 4 expected
Valid From: 2026 May 07 1635 UTC
Valid To: 2026 May 08 1500 UTC
Warning Condition: Onset

NOAA Space Weather Scale descriptions can be found at
www.swpc.noaa.gov/noaa-scales-explanation

Potential Impacts: Area of impact primarily poleward of 65 degrees Geomagnetic Latitude.
Induced Currents - Weak power grid fluctuations can occur.
Aurora - Aurora may be visible at high latitudes such as Canada and Alaska.