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Solar activity report

Report of Solar-Geophysical Activity 2021 May 23 2200 UTC
Prepared by the NOAA © SWPC and processed by

Joint USAF/NOAA Report of Solar and Geophysical Activity

SDF Number 143 Issued at 2200Z on 23 May 2021

IA. Analysis of Solar Active Regions and Activity from 22-2100Z to 23-2100Z

Solar activity has been at moderate levels for the past 24 hours. The largest solar event of the period was a M1 event observed at 22/2136Z from Region 2824 (N21E13). There are currently 2 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 (24 May, 25 May, 26 May).
IIA. Geophysical Activity Summary 22-2100Z to 23-2100Z
The geomagnetic field has been at quiet levels for the past 24 hours. Solar wind speed reached a peak of 474 km/s at 22/2144Z. Electrons greater than 2 MeV at geosynchronous orbit reached a peak level of 794 pfu.
IIB. Geophysical Activity Forecast
The geomagnetic field is expected to be at quiet levels on day one (24 May), quiet to minor storm levels on day two (25 May) and unsettled to major storm levels on day three (26 May).
III. Event Probabilities 24 May to 26 May
Class M25%25%25%
Class X01%01%01%
IV. Penticton 10.7 cm Flux
  Observed       23 May 079
  Predicted   24 May-26 May 079/079/079
  90 Day Mean        23 May 076

V. Geomagnetic A Indices
  Observed Afr/Ap 22 May  005/004
  Estimated     Afr/Ap 23 May  004/005
  Predicted    Afr/Ap 24 May-26 May  006/005-011/008-028/042

VI. Geomagnetic Activity Probabilities 24 May to 26 May
A. Middle Latitudes
Minor storm01%15%30%
Major-severe storm01%01%10%
B. High Latitudes
Minor storm20%30%25%
Major-severe storm10%50%65%

All times in UTC

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