:Product: 1215RSGA.txt
:Issued: 2021 Dec 15 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 349 Issued at 2200Z on 15 Dec 2021

IA.  Analysis of Solar Active Regions and Activity from 14/2100Z to
15/2100Z: Solar activity has been at low levels for the past 24 hours.
The largest solar event of the period was a C8 event observed at
15/1044Z from Region 2907 (S21E39). 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 day one (16 Dec) and likely to be low
with a slight chance for an M-class flare on days two and three (17 Dec,
18 Dec).

IIA.  Geophysical Activity Summary 14/2100Z to 15/2100Z: The geomagnetic
field has been at quiet to unsettled levels for the past 24 hours. Solar
wind speed reached a peak of 568 km/s at 15/1236Z. Total IMF reached 16
nT at 15/0517Z. The maximum southward component of Bz reached -14 nT at
15/0517Z.  Electrons greater than 2 MeV at geosynchronous orbit reached
a peak level of 152 pfu.
IIB.  Geophysical Activity Forecast: The geomagnetic field is expected
to be at quiet to unsettled levels on days one and two (16 Dec, 17 Dec)
and quiet levels on day three (18 Dec).

III.  Event probabilities 16 Dec-18 Dec
Class M    25/20/15
Class X    01/01/01
Proton     01/01/01
PCAF       green

IV.  Penticton 10.7 cm Flux
Observed           15 Dec 103
Predicted   16 Dec-18 Dec 102/102/102
90 Day Mean        15 Dec 087

V.  Geomagnetic A Indices
Observed Afr/Ap 14 Dec  004/004
Estimated Afr/Ap 15 Dec  009/011
Predicted Afr/Ap 16 Dec-18 Dec  008/008-008/008-006/005

VI.  Geomagnetic Activity Probabilities 16 Dec-18 Dec
A.  Middle Latitudes
Active                25/15/10
Minor Storm           05/05/01
Major-severe storm    01/01/01
B.  High Latitudes
Active                15/15/15
Minor Storm           30/25/20
Major-severe storm    30/25/20