:Product: 0928RSGA.txt
:Issued: 2025 Sep 28 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 271 Issued at 2200Z on 28 Sep 2025

IA.  Analysis of Solar Active Regions and Activity from 27/2100Z to
28/2100Z: Solar activity has been at high levels for the past 24 hours.
There are currently 9 numbered sunspot regions on the disk.
IB.  Solar Activity Forecast: Solar activity is likely to be moderate
with a slight chance for an X-class flare on days one, two, and three
(29 Sep, 30 Sep, 01 Oct).

IIA.  Geophysical Activity Summary 27/2100Z to 28/2100Z: The geomagnetic
field has been at quiet to unsettled levels for the past 24 hours. Solar
wind speed reached a peak of 447 km/s at 28/1512Z. Total IMF reached 13
nT at 28/1843Z. The maximum southward component of Bz reached -6 nT at
28/0022Z.  Electrons greater than 2 MeV at geosynchronous orbit reached
a peak level of 445 pfu.
IIB.  Geophysical Activity Forecast: The geomagnetic field is expected
to be at quiet to active levels on day one (29 Sep), quiet to unsettled
levels on day two (30 Sep) and quiet levels on day three (01 Oct).

III.  Event probabilities 29 Sep-01 Oct
Class M    55/55/55
Class X    10/10/10
Proton     01/01/01
PCAF       green

IV.  Penticton 10.7 cm Flux
Observed           28 Sep 171
Predicted   29 Sep-01 Oct 175/180/180
90 Day Mean        28 Sep 149

V.  Geomagnetic A Indices
Observed Afr/Ap 27 Sep  005/006
Estimated Afr/Ap 28 Sep  010/012
Predicted Afr/Ap 29 Sep-01 Oct  013/014-008/008-006/005

VI.  Geomagnetic Activity Probabilities 29 Sep-01 Oct
A.  Middle Latitudes
Active                30/25/10
Minor Storm           10/10/01
Major-severe storm    01/01/01
B.  High Latitudes
Active                15/15/15
Minor Storm           30/30/20
Major-severe storm    40/35/20
