:Product: 0520RSGA.txt
:Issued: 2025 May 21 0200 UTC
# Prepared jointly by the U.S. Dept. of Commerce, NOAA,
# Space Weather Prediction Center and the U.S. Air Force.
#
Joint USAF/NOAA Solar Geophysical Activity Report and Forecast
SDF Number 140 Issued at 2200Z on 20 May 2025

IA.  Analysis of Solar Active Regions and Activity from 19/2100Z to
20/2100Z: Solar activity has been at low levels for the past 24 hours.
There are currently 5 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 (21 May, 22 May,
23 May).

IIA.  Geophysical Activity Summary 19/2100Z to 20/2100Z: The geomagnetic
field has been at quiet to unsettled levels for the past 24 hours. Solar
wind speed reached a peak of 617 km/s at 20/2158Z. Total IMF reached 10
nT at 20/1352Z. The maximum southward component of Bz reached -8 nT at
20/1037Z.  Electrons greater than 2 MeV at geosynchronous orbit reached
a peak level of 1309 pfu.
IIB.  Geophysical Activity Forecast: The geomagnetic field is expected
to be at quiet to unsettled levels on days one and two (21 May, 22 May)
and quiet to active levels on day three (23 May).

III.  Event probabilities 21 May-23 May
Class M    35/35/35
Class X    05/05/05
Proton     01/01/01
PCAF       green

IV.  Penticton 10.7 cm Flux
Observed           20 May 119
Predicted   21 May-23 May 118/120/120
90 Day Mean        20 May 159

V.  Geomagnetic A Indices
Observed Afr/Ap 19 May  010/ 010
Estimated Afr/Ap 20 May  012/013
Predicted Afr/Ap 21 May-23 May  010/012-007/010-009/012

VI.  Geomagnetic Activity Probabilities 21 May-23 May
A.  Middle Latitudes
Active                30/15/15
Minor Storm           15/05/01
Major-severe storm    01/01/01
B.  High Latitudes
Active                15/15/15
Minor Storm           30/25/25
Major-severe storm    45/25/20
