:Product: 0920RSGA.txt
:Issued: 2026 Sep 20 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 263 Issued at 2200Z on 20 Sep 2026

IA.  Analysis of Solar Active Regions and Activity from 19/2100Z to
20/2100Z: Solar activity has been at low levels for the past 24 hours.
There are currently 4 numbered sunspot regions on the disk.
IB.  Solar Activity Forecast: Solar activity is expected to be very low
with a chance for a C-class flares on days one, two, and three (21 Sep,
22 Sep, 23 Sep).

IIA.  Geophysical Activity Summary 19/2100Z to 20/2100Z: The geomagnetic
field has been at quiet to unsettled levels for the past 24 hours. Solar
wind speed reached a peak of 430 km/s. Total IMF reached 5 nT. The
maximum southward component of Bz reached -4 nT.  Electrons greater than
2 MeV at geosynchronous orbit reached a peak level of 627 pfu.
IIB.  Geophysical Activity Forecast: The geomagnetic field is expected
to be at quiet levels on days one, two, and three (21 Sep, 22 Sep, 23
Sep).

III.  Event probabilities 21 Sep-23 Sep
Class M    01/01/01
Class X    01/01/01
Proton     01/01/01
PCAF       green

IV.  Penticton 10.7 cm Flux
Observed           20 Sep 101
Predicted   21 Sep-23 Sep 105/105/100
90 Day Mean        20 Sep 125

V.  Geomagnetic A Indices
Observed Afr/Ap 19 Sep  006/007
Estimated Afr/Ap 20 Sep  006/006
Predicted Afr/Ap 21 Sep-23 Sep  005/005-006/005-006/005

VI.  Geomagnetic Activity Probabilities 21 Sep-23 Sep
A.  Middle Latitudes
Active                10/10/10
Minor Storm           05/05/05
Major-severe storm    01/01/01
B.  High Latitudes
Active                15/15/15
Minor Storm           20/15/15
Major-severe storm    15/15/15