Viewing archive of Thursday, 18 May 2023
Solar activity report
Report of Solar-Geophysical Activity 2023 May 18 2200 UTCPrepared by the NOAA © SWPC and processed by SpaceWeatherLive.com
Joint USAF/NOAA Report of Solar and Geophysical Activity
SDF Number 138 Issued at 2200Z on 18 May 2023IA. Analysis of Solar Active Regions and Activity from 17-2100Z to 18-2100Z Solar activity has been at moderate levels for the past 24
hours. The largest solar event of the period was a M2 event observed at
18/1147Z from Region 3311 (N18E76). There are currently 8 numbered
sunspot regions on the disk.
IB. Solar Activity Forecast
Solar activity is expected to be low with
a chance for M-class flares on days one, two, and three (19 May, 20 May,
21 May).
IIA. Geophysical Activity Summary 17-2100Z to 18-2100Z
The geomagnetic
field has been at quiet levels for the past 24 hours. Solar wind speed
reached a peak of 501 km/s at 18/1058Z. Electrons greater than 2 MeV at
geosynchronous orbit reached a peak level of 174 pfu.
IIB. Geophysical Activity Forecast
The geomagnetic field is expected
to be at quiet levels on day one (19 May), quiet to unsettled levels on
day two (20 May) and quiet to active levels on day three (21 May).
III. Event Probabilities 19 May to 21 May
| Class M | 35% | 25% | 25% |
| Class X | 05% | 05% | 05% |
| Proton | 01% | 01% | 01% |
| PCAF | green | ||
IV. Penticton 10.7 cm Flux
Observed 18 May 151 Predicted 19 May-21 May 145/140/140 90 Day Mean 18 May 153
V. Geomagnetic A Indices
Observed Afr/Ap 17 May 005/004 Estimated Afr/Ap 18 May 004/004 Predicted Afr/Ap 19 May-21 May 006/005-007/008-010/012
VI. Geomagnetic Activity Probabilities 19 May to 21 May
| A. Middle Latitudes | |||
|---|---|---|---|
| Active | 10% | 20% | 25% |
| Minor storm | 01% | 05% | 05% |
| Major-severe storm | 01% | 01% | 01% |
| B. High Latitudes | |||
|---|---|---|---|
| Active | 15% | 15% | 15% |
| Minor storm | 20% | 20% | 25% |
| Major-severe storm | 10% | 25% | 40% |
All times in UTC
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