:Product: 0831RSGA.txt
:Issued: 2025 Aug 31 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 243 Issued at 2200Z on 31 Aug 2025

IA.  Analysis of Solar Active Regions and Activity from 30/2100Z to
31/2100Z: Solar activity has been at low levels for the past 24 hours.
There are currently 10 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
(01 Sep, 02 Sep, 03 Sep).

IIA.  Geophysical Activity Summary 30/2100Z to 31/2100Z: The geomagnetic
field has been at quiet to unsettled levels for the past 24 hours. Solar
wind speed reached a peak of 499 km/s at 31/1856Z. Total IMF reached 10
nT at 31/0249Z. The maximum southward component of Bz reached -7 nT at
31/0720Z.  Electrons greater than 2 MeV at geosynchronous orbit reached
a peak level of 393 pfu.
IIB.  Geophysical Activity Forecast: The geomagnetic field is expected
to be at quiet to major storm levels on day one (01 Sep), active to
severe storm levels on day two (02 Sep) and quiet to active levels on
day three (03 Sep). Protons have a slight chance of crossing threshold
on days one, two, and three (01 Sep, 02 Sep, 03 Sep).

III.  Event probabilities 01 Sep-03 Sep
Class M    65/65/65
Class X    20/20/20
Proton     10/10/10
PCAF       green

IV.  Penticton 10.7 cm Flux
Observed           31 Aug 217
Predicted   01 Sep-03 Sep 215/210/200
90 Day Mean        31 Aug 143

V.  Geomagnetic A Indices
Observed Afr/Ap 30 Aug  008/008
Estimated Afr/Ap 31 Aug  007/010
Predicted Afr/Ap 01 Sep-03 Sep  016/020-039/055-009/010

VI.  Geomagnetic Activity Probabilities 01 Sep-03 Sep
A.  Middle Latitudes
Active                25/25/35
Minor Storm           40/35/15
Major-severe storm    30/35/01
B.  High Latitudes
Active                05/05/10
Minor Storm           15/15/30
Major-severe storm    79/85/50
