:Product: 1228RSGA.txt
:Issued: 2021 Dec 28 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 362 Issued at 2200Z on 28 Dec 2021

IA.  Analysis of Solar Active Regions and Activity from 27/2100Z to
28/2100Z: 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
28/0401Z from Region 2918 (N21W26). There are currently 5 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 (29 Dec, 30 Dec,
31 Dec).

IIA.  Geophysical Activity Summary 27/2100Z to 28/2100Z: The geomagnetic
field has been at quiet to unsettled levels for the past 24 hours. Solar
wind speed reached a peak of 551 km/s at 28/1500Z. Total IMF reached 10
nT at 28/0125Z. The maximum southward component of Bz reached -8 nT at
28/0330Z.  Electrons greater than 2 MeV at geosynchronous orbit reached
a peak level of 284 pfu.
IIB.  Geophysical Activity Forecast: The geomagnetic field is expected
to be at quiet to active levels on day one (29 Dec) and quiet to
unsettled levels on days two and three (30 Dec, 31 Dec).

III.  Event probabilities 29 Dec-31 Dec
Class M    25/25/25
Class X    05/05/05
Proton     05/05/05
PCAF       green

IV.  Penticton 10.7 cm Flux
Observed           28 Dec 121
Predicted   29 Dec-31 Dec 122/122/120
90 Day Mean        28 Dec 093

V.  Geomagnetic A Indices
Observed Afr/Ap 27 Dec  008/009
Estimated Afr/Ap 28 Dec  009/010
Predicted Afr/Ap 29 Dec-31 Dec  013/014-007/010-007/008

VI.  Geomagnetic Activity Probabilities 29 Dec-31 Dec
A.  Middle Latitudes
Active                30/25/20
Minor Storm           15/05/05
Major-severe storm    01/01/01
B.  High Latitudes
Active                15/15/20
Minor Storm           30/30/30
Major-severe storm    45/30/25