:Product: 1222RSGA.txt
:Issued: 2023 Dec 22 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 356 Issued at 2200Z on 22 Dec 2023

IA.  Analysis of Solar Active Regions and Activity from 21/2100Z to
22/2100Z: Solar activity has been at moderate levels for the past 24
hours. The largest solar event of the period was a M3 event observed at
22/0004Z from Region 3519 (S10W86). There are currently 10 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 (23 Dec, 24 Dec,
25 Dec).

IIA.  Geophysical Activity Summary 21/2100Z to 22/2100Z: The geomagnetic
field has been at quiet levels for the past 24 hours. Solar wind speed
reached a peak of 381 km/s at 22/0154Z. Total IMF reached 6 nT at
22/0826Z. The maximum southward component of Bz reached -4 nT at
22/0748Z.  Electrons greater than 2 MeV at geosynchronous orbit reached
a peak level of 1867 pfu.
IIB.  Geophysical Activity Forecast: The geomagnetic field is expected
to be at quiet to active levels on day one (23 Dec), quiet to unsettled
levels on day two (24 Dec) and quiet levels on day three (25 Dec).

III.  Event probabilities 23 Dec-25 Dec
Class M    35/25/25
Class X    05/01/01
Proton     05/01/01
PCAF       green

IV.  Penticton 10.7 cm Flux
Observed           22 Dec 187
Predicted   23 Dec-25 Dec 185/185/180
90 Day Mean        22 Dec 150

V.  Geomagnetic A Indices
Observed Afr/Ap 21 Dec  003/004
Estimated Afr/Ap 22 Dec  004/004
Predicted Afr/Ap 23 Dec-25 Dec  010/012-008/008-006/005

VI.  Geomagnetic Activity Probabilities 23 Dec-25 Dec
A.  Middle Latitudes
Active                25/10/05
Minor Storm           10/05/01
Major-severe storm    01/01/01
B.  High Latitudes
Active                15/15/15
Minor Storm           20/20/20
Major-severe storm    25/20/10