:Product: 0923RSGA.txt
:Issued: 2023 Sep 23 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 266 Issued at 2200Z on 23 Sep 2023

IA.  Analysis of Solar Active Regions and Activity from 22/2100Z to
23/2100Z: Solar activity has been at moderate levels for the past 24
hours. The largest solar event of the period was a M1 event observed at
22/2300Z from Region 3443 (N28W40). There are currently 12 numbered
sunspot regions on the disk.
IB.  Solar Activity Forecast: Solar activity is likely to be moderate
with a slight chance for an X-class flare on days one, two, and three
(24 Sep, 25 Sep, 26 Sep).

IIA.  Geophysical Activity Summary 22/2100Z to 23/2100Z: The geomagnetic
field has been at quiet to unsettled levels for the past 24 hours. Solar
wind speed reached a peak of 395 km/s at 23/0034Z. Total IMF reached 5
nT at 23/1008Z. The maximum southward component of Bz reached -5 nT at
23/1717Z.  Electrons greater than 2 MeV at geosynchronous orbit reached
a peak level of 2394 pfu.
IIB.  Geophysical Activity Forecast: The geomagnetic field is expected
to be at quiet to minor storm levels on day one (24 Sep) and quiet to
active levels on days two and three (25 Sep, 26 Sep). Protons have a
slight chance of crossing threshold on days one, two, and three (24 Sep,
25 Sep, 26 Sep).

III.  Event probabilities 24 Sep-26 Sep
Class M    60/60/60
Class X    15/15/15
Proton     10/10/10
PCAF       green

IV.  Penticton 10.7 cm Flux
Observed           23 Sep 173
Predicted   24 Sep-26 Sep 175/172/168
90 Day Mean        23 Sep 162

V.  Geomagnetic A Indices
Observed Afr/Ap 22 Sep  007/010
Estimated Afr/Ap 23 Sep  010/010
Predicted Afr/Ap 24 Sep-26 Sep  018/022-013/015-009/012

VI.  Geomagnetic Activity Probabilities 24 Sep-26 Sep
A.  Middle Latitudes
Active                35/25/20
Minor Storm           20/05/05
Major-severe storm    05/01/01
B.  High Latitudes
Active                15/15/15
Minor Storm           20/20/20
Major-severe storm    30/25/20