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Solar activity report
Report of Solar-Geophysical Activity 2023 May 21 2200 UTCPrepared by the NOAA © SWPC and processed by SpaceWeatherLive.com
Joint USAF/NOAA Report of Solar and Geophysical Activity
SDF Number 141 Issued at 2200Z on 21 May 2023IA. Analysis of Solar Active Regions and Activity from 20-2100Z to 21-2100Z Solar activity has been at high levels for the past 24 hours.
The largest solar event of the period was a M5 event observed at
20/2306Z from Region 3311 (N18E47). There are currently 8 numbered
sunspot regions on the disk.
IB. Solar Activity Forecast
Solar activity is expected to be moderate
with a chance for X-class flares on days one, two, and three (22 May, 23
May, 24 May).
IIA. Geophysical Activity Summary 20-2100Z to 21-2100Z
The geomagnetic
field has been at quiet to major storm levels for the past 24 hours.
Solar wind speed reached a peak of 632 km/s at 20/2216Z. Total IMF
reached 13 nT at 21/1516Z. The maximum southward component of Bz reached
-10 nT at 21/1935Z. Electrons greater than 2 MeV at geosynchronous
orbit reached a peak level of 1084 pfu.
IIB. Geophysical Activity Forecast
The geomagnetic field is expected
to be at quiet to major storm levels on day one (22 May), quiet to minor
storm levels on day two (23 May) and unsettled to minor storm levels on
day three (24 May). Protons have a slight chance of crossing threshold
on days one, two, and three (22 May, 23 May, 24 May).
III. Event Probabilities 22 May to 24 May
| Class M | 75% | 75% | 75% |
| Class X | 30% | 30% | 30% |
| Proton | 15% | 15% | 15% |
| PCAF | green | ||
IV. Penticton 10.7 cm Flux
Observed 21 May 163 Predicted 22 May-24 May 160/155/150 90 Day Mean 21 May 153
V. Geomagnetic A Indices
Observed Afr/Ap 20 May 026/030 Estimated Afr/Ap 21 May 013/021 Predicted Afr/Ap 22 May-24 May 016/022-014/018-020/022
VI. Geomagnetic Activity Probabilities 22 May to 24 May
| A. Middle Latitudes | |||
|---|---|---|---|
| Active | 35% | 35% | 35% |
| Minor storm | 35% | 20% | 30% |
| Major-severe storm | 20% | 05% | 15% |
| B. High Latitudes | |||
|---|---|---|---|
| Active | 10% | 15% | 15% |
| Minor storm | 25% | 20% | 25% |
| Major-severe storm | 60% | 20% | 50% |
All times in UTC
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