:Product: 0927RSGA.txt
:Issued: 2025 Sep 27 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 270 Issued at 2200Z on 27 Sep 2025

IA.  Analysis of Solar Active Regions and Activity from 26/2100Z to
27/2100Z: Solar activity has been at moderate 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 on
days one, two, and three (28 Sep, 29 Sep, 30 Sep).

IIA.  Geophysical Activity Summary 26/2100Z to 27/2100Z: The geomagnetic
field has been at quiet to unsettled levels for the past 24 hours. Solar
wind speed reached a peak of 434 km/s at 26/2115Z. Total IMF reached 10
nT at 27/2058Z. The maximum southward component of Bz reached -8 nT at
27/1857Z.  Electrons greater than 2 MeV at geosynchronous orbit reached
a peak level of 1723 pfu.
IIB.  Geophysical Activity Forecast: The geomagnetic field is expected
to be at quiet to active levels on days one and two (28 Sep, 29 Sep) and
quiet to unsettled levels on day three (30 Sep).

III.  Event probabilities 28 Sep-30 Sep
Class M    55/55/55
Class X    05/05/05
Proton     01/01/01
PCAF       green

IV.  Penticton 10.7 cm Flux
Observed           27 Sep 164
Predicted   28 Sep-30 Sep 165/160/160
90 Day Mean        27 Sep 149

V.  Geomagnetic A Indices
Observed Afr/Ap 26 Sep  006/007
Estimated Afr/Ap 27 Sep  007/007
Predicted Afr/Ap 28 Sep-30 Sep  013/018-011/014-007/008

VI.  Geomagnetic Activity Probabilities 28 Sep-30 Sep
A.  Middle Latitudes
Active                30/30/25
Minor Storm           15/10/10
Major-severe storm    01/01/01
B.  High Latitudes
Active                15/15/15
Minor Storm           30/30/30
Major-severe storm    45/40/35
