:Product: 0918RSGA.txt
:Issued: 2025 Sep 18 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 261 Issued at 2200Z on 18 Sep 2025

IA.  Analysis of Solar Active Regions and Activity from 17/2100Z to
18/2100Z: 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 expected to be low with
a chance for M-class flares on days one, two, and three (19 Sep, 20 Sep,
21 Sep).

IIA.  Geophysical Activity Summary 17/2100Z to 18/2100Z: The geomagnetic
field has been at quiet to unsettled levels for the past 24 hours. Solar
wind speed reached a peak of 614 km/s at 18/0328Z.  Electrons greater
than 2 MeV at geosynchronous orbit reached a peak level of 6213 pfu.
IIB.  Geophysical Activity Forecast: The geomagnetic field is expected
to be at quiet levels on days one and two (19 Sep, 20 Sep) and quiet to
active levels on day three (21 Sep).

III.  Event probabilities 19 Sep-21 Sep
Class M    35/35/35
Class X    01/01/01
Proton     01/01/01
PCAF       green

IV.  Penticton 10.7 cm Flux
Observed           18 Sep 150
Predicted   19 Sep-21 Sep 150/150/150
90 Day Mean        18 Sep 144

V.  Geomagnetic A Indices
Observed Afr/Ap 17 Sep  010/012
Estimated Afr/Ap 18 Sep  007/007
Predicted Afr/Ap 19 Sep-21 Sep  006/005-006/005-012/015

VI.  Geomagnetic Activity Probabilities 19 Sep-21 Sep
A.  Middle Latitudes
Active                10/10/30
Minor Storm           01/01/10
Major-severe storm    01/01/01
B.  High Latitudes
Active                15/15/15
Minor Storm           20/20/30
Major-severe storm    20/20/40
