:Product: 1219RSGA.txt
:Issued: 2021 Dec 19 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 353 Issued at 2200Z on 19 Dec 2021

IA.  Analysis of Solar Active Regions and Activity from 18/2100Z to
19/2100Z: Solar activity has been at low levels for the past 24 hours.
The largest solar event of the period was a C1 event observed at
19/1916Z from Region 2907 (S21W14). There are currently 7 numbered
sunspot regions on the disk.
IB.  Solar Activity Forecast: Solar activity is expected to be low with
a slight chance for an M-class flare on days one, two, and three (20
Dec, 21 Dec, 22 Dec).

IIA.  Geophysical Activity Summary 18/2100Z to 19/2100Z: The geomagnetic
field has been at quiet to active levels for the past 24 hours. Solar
wind speed reached a peak of 461 km/s at 19/2051Z. Total IMF reached 23
nT at 19/2034Z. The maximum southward component of Bz reached -20 nT at
19/2038Z.  Electrons greater than 2 MeV at geosynchronous orbit reached
a peak level of 477 pfu.
IIB.  Geophysical Activity Forecast: The geomagnetic field is expected
to be at quiet to active levels on days one, two, and three (20 Dec, 21
Dec, 22 Dec).

III.  Event probabilities 20 Dec-22 Dec
Class M    20/20/20
Class X    05/05/05
Proton     05/05/05
PCAF       green

IV.  Penticton 10.7 cm Flux
Observed           19 Dec 115
Predicted   20 Dec-22 Dec 115/115/114
90 Day Mean        19 Dec 089

V.  Geomagnetic A Indices
Observed Afr/Ap 18 Dec  002/002
Estimated Afr/Ap 19 Dec  007/010
Predicted Afr/Ap 20 Dec-22 Dec  010/012-012/016-010/012

VI.  Geomagnetic Activity Probabilities 20 Dec-22 Dec
A.  Middle Latitudes
Active                25/30/25
Minor Storm           05/15/05
Major-severe storm    01/01/01
B.  High Latitudes
Active                15/15/15
Minor Storm           30/30/30
Major-severe storm    30/45/30