:Product: Report of Solar-Geophysical Activity
:Issued: 2025 Sep 15 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 258 Issued at 2200Z on 15 Sep 2025

IA.  Analysis of Solar Active Regions and Activity from 14/2100Z to
15/2100Z: Solar activity has been at low levels for the past 24 hours.
There are currently 6 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 (16 Sep, 17 Sep,
18 Sep).

IIA.  Geophysical Activity Summary 14/2100Z to 15/2100Z: The geomagnetic
field has been at active to severe storm levels for the past 24 hours.
Solar wind speed reached a peak of 823 km/s at 15/0553Z. Total IMF
reached 19 nT at 14/2232Z. The maximum southward component of Bz reached
-16 nT at 14/2338Z.  Electrons greater than 2 MeV at geosynchronous
orbit reached a peak level of 417 pfu.
IIB.  Geophysical Activity Forecast: The geomagnetic field is expected
to be at quiet to minor storm levels on day one (16 Sep), quiet to
active levels on day two (17 Sep) and quiet to unsettled levels on day
three (18 Sep).

III.  Event probabilities 16 Sep-18 Sep
Class M    30/30/30
Class X    05/05/05
Proton     01/01/01
PCAF       green

IV.  Penticton 10.7 cm Flux
Observed           15 Sep 130
Predicted   16 Sep-18 Sep 130/130/135
90 Day Mean        15 Sep 144

V.  Geomagnetic A Indices
Observed Afr/Ap 14 Sep  012/014
Estimated Afr/Ap 15 Sep  032/051
Predicted Afr/Ap 16 Sep-18 Sep  020/024-013/015-009/010

VI.  Geomagnetic Activity Probabilities 16 Sep-18 Sep
A.  Middle Latitudes
Active                35/30/20
Minor Storm           30/10/05
Major-severe storm    15/01/01
B.  High Latitudes
Active                05/15/15
Minor Storm           20/30/25
Major-severe storm    70/40/30