:Product: 0920RSGA.txt
:Issued: 2025 Sep 20 2200 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 263 Issued at 2200Z on 20 Sep 2025

IA.  Analysis of Solar Active Regions and Activity from 19/2100Z to
20/2100Z: Solar activity has been at moderate levels for the past 24
hours. There are currently 10 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 Sep, 22 Sep,
23 Sep).

IIA.  Geophysical Activity Summary 19/2100Z to 20/2100Z: The geomagnetic
field has been at quiet levels for the past 24 hours. Solar wind speed
reached a peak of 457 km/s at 19/2100Z.  Electrons greater than 2 MeV at
geosynchronous orbit reached a peak level of 4444 pfu.
IIB.  Geophysical Activity Forecast: The geomagnetic field is expected
to be at unsettled to active levels on day one (21 Sep), unsettled to
minor storm levels on day two (22 Sep) and quiet to unsettled levels on
day three (23 Sep).

III.  Event probabilities 21 Sep-23 Sep
Class M    40/40/40
Class X    05/05/05
Proton     05/05/05
PCAF       green

IV.  Penticton 10.7 cm Flux
Observed           20 Sep 166
Predicted   21 Sep-23 Sep 165/170/170
90 Day Mean        20 Sep 145

V.  Geomagnetic A Indices
Observed Afr/Ap 19 Sep  007/003
Estimated Afr/Ap 20 Sep  005/005
Predicted Afr/Ap 21 Sep-23 Sep  015/018-019/024-009/012

VI.  Geomagnetic Activity Probabilities 21 Sep-23 Sep
A.  Middle Latitudes
Active                30/40/20
Minor Storm           10/25/05
Major-severe storm    01/05/01
B.  High Latitudes
Active                15/10/15
Minor Storm           30/25/25
Major-severe storm    40/60/25
