:Product: 1216RSGA.txt
:Issued: 2025 Dec 16 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 350 Issued at 2200Z on 16 Dec 2025

IA.  Analysis of Solar Active Regions and Activity from 15/2100Z to
16/2100Z: Solar activity has been at low levels for the past 24 hours.
There are currently 6 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 (17
Dec, 18 Dec, 19 Dec).

IIA.  Geophysical Activity Summary 15/2100Z to 16/2100Z: The geomagnetic
field has been at quiet to unsettled levels for the past 24 hours. Solar
wind speed reached a peak of 737 km/s at 16/1353Z. Total IMF reached 13
nT at 16/0136Z. The maximum southward component of Bz reached -7 nT at
15/2350Z.  Electrons greater than 2 MeV at geosynchronous orbit reached
a peak level of 1024 pfu.
IIB.  Geophysical Activity Forecast: The geomagnetic field is expected
to be at quiet to active levels on days one and two (17 Dec, 18 Dec) and
quiet to unsettled levels on day three (19 Dec).

III.  Event probabilities 17 Dec-19 Dec
Class M    15/15/15
Class X    01/01/01
Proton     01/01/01
PCAF       green

IV.  Penticton 10.7 cm Flux
Observed           16 Dec 117
Predicted   17 Dec-19 Dec 118/118/115
90 Day Mean        16 Dec 150

V.  Geomagnetic A Indices
Observed Afr/Ap 15 Dec  005/006
Estimated Afr/Ap 16 Dec  010/011
Predicted Afr/Ap 17 Dec-19 Dec  013/015-014/015-009/010

VI.  Geomagnetic Activity Probabilities 17 Dec-19 Dec
A.  Middle Latitudes
Active                35/35/25
Minor Storm           20/15/10
Major-severe storm    05/05/01
B.  High Latitudes
Active                10/10/15
Minor Storm           25/25/25
Major-severe storm    50/50/35
