:Product: Report of Solar-Geophysical Activity
:Issued: 2026 Sep 12 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 255 Issued at 2200Z on 12 Sep 2026

IA.  Analysis of Solar Active Regions and Activity from 11/2100Z to
12/2100Z: Solar activity has been at low levels for the past 24 hours.
There are currently 7 numbered sunspot regions on the disk.
IB.  Solar Activity Forecast: Solar activity is likely to be low with a
slight chance for an M-class flare on days one, two, and three (13 Sep,
14 Sep, 15 Sep).

IIA.  Geophysical Activity Summary 11/2100Z to 12/2100Z: 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 12/0150Z. Total IMF reached 7
nT at 12/1947Z. The maximum southward component of Bz reached 6 nT at
12/0553Z.  Electrons greater than 2 MeV at geosynchronous orbit reached
a peak level of 2662 pfu.
IIB.  Geophysical Activity Forecast: The geomagnetic field is expected
to be at quiet to unsettled levels on days one and three (13 Sep, 15
Sep) and unsettled to active levels on day two (14 Sep).

III.  Event probabilities 13 Sep-15 Sep
Class M    10/10/10
Class X    01/01/01
Proton     01/01/01
PCAF       green

IV.  Penticton 10.7 cm Flux
Observed           12 Sep 109
Predicted   13 Sep-15 Sep 105/105/100
90 Day Mean        12 Sep 126

V.  Geomagnetic A Indices
Observed Afr/Ap 11 Sep  009/008
Estimated Afr/Ap 12 Sep  007/008
Predicted Afr/Ap 13 Sep-15 Sep  008/010-014/018-013/016

VI.  Geomagnetic Activity Probabilities 13 Sep-15 Sep
A.  Middle Latitudes
Active                20/30/25
Minor Storm           05/05/05
Major-severe storm    01/01/01
B.  High Latitudes
Active                15/15/15
Minor Storm           20/20/20
Major-severe storm    20/20/20