Viewing archive of Sunday, 16 July 2017

Daily bulletin on solar and geomagnetic activity from the SIDC

Issued: 2017 Jul 16 1319 UTC

SIDC Forecast

Valid from 1230 UTC, 16 Jul 2017 until 18 Jul 2017
Solar flares

C-class flares expected, (probability >=50%)

Geomagnetism

Minor storm expected (A>=30 or K=5)

Solar protons

Quiet

10cm fluxAp
16 Jul 2017094032
17 Jul 2017095006
18 Jul 2017096005

Bulletin

NOAA AR 2665 produced three B and five C-class flares during the past 24 hours. The most intensive flare was C5.8-class flare peaking at 19:36 UT on 15th July. No Earth directed Coronal Mass Ejections (CMEs) have been detected. The integral flux of protons with energy above 10 MeV is still elevated at the level 4 pfu and is expected to decrease further. A coronal mass ejection (CME) of July 14th has arrived today on July 16th at approximately 05:45 UT. A large positive polarity coronal hole will approach geoeffective position in 4 days. More C-class flares are expected tomorrow. Solar wind parameters were very quiet till approximately 05:45 UT today. Then a coronal mass ejection (CME) of July 14th has arrived. Solar wind speed jumped from about 320 km/s to 505 km/s, and total magnetic field strength Bt from 3.5 to 22 nT. Solar wind density jumped from 5/cm^3 till 51/cm^3 and temperature from 1.2* 10^4 K till 3.0*10^5 K. Bz variations increased first from -2/+2 nT till +7/-12 nT and later Bz decreased till -22 nT and remained at this level during 10:00 - 12:00 UT time interval.

Geomagnetic conditions remained at very low levels till 06:00 UT, then Kp increased till Kp = 4 [06-09 UT], Kp = 5 [09-12 UT]. Local index in Dourbes is at K=4 level. We expect geomagnetic conditions to remain at minor storm level for several hours after which it will return to quiet levels. Dst index is expected to go down till -120.

Today's estimated international sunspot number (ISN): 021, based on 15 stations.

Solar indices for 15 Jul 2017

Wolf number Catania///
10cm solar flux092
AK Chambon La Forêt008
AK Wingst005
Estimated Ap003
Estimated international sunspot number032 - Based on 30 stations

Noticeable events summary

DayBeginMaxEndLocStrengthOP10cmCatania/NOAARadio burst types
None

Provided by the Solar Influences Data analysis Center© - SIDC - Processed by SpaceWeatherLive

All times in UTC

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