:Product: 1209RSGA.txt
:Issued: 2025 Dec 09 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 343 Issued at 2200Z on 09 Dec 2025

IA.  Analysis of Solar Active Regions and Activity from 08/2100Z to
09/2100Z: Solar activity has been at high levels for the past 24 hours.
There are currently 8 numbered sunspot regions on the disk.
IB.  Solar Activity Forecast: Solar activity is likely to be moderate
with a slight chance for an X-class flare on days one, two, and three
(10 Dec, 11 Dec, 12 Dec).

IIA.  Geophysical Activity Summary 08/2100Z to 09/2100Z: The geomagnetic
field has been at quiet levels for the past 24 hours. Solar wind speed
reached a peak of 671 km/s at 09/1305Z. Total IMF reached 9 nT at
09/1250Z. The maximum southward component of Bz reached -5 nT at
09/1222Z.  Electrons greater than 2 MeV at geosynchronous orbit reached
a peak level of 1572 pfu.
IIB.  Geophysical Activity Forecast: The geomagnetic field is expected
to be at quiet to unsettled levels on days one, two, and three (10 Dec,
11 Dec, 12 Dec). Protons greater than 10 Mev have a slight chance of
crossing threshold on day one (10 Dec) and have a slight chance of
crossing threshold on day two (11 Dec).

III.  Event probabilities 10 Dec-12 Dec
Class M    65/65/65
Class X    15/15/10
Proton     15/10/05
PCAF       green

IV.  Penticton 10.7 cm Flux
Observed           09 Dec 183
Predicted   10 Dec-12 Dec 180/175/160
90 Day Mean        09 Dec 150

V.  Geomagnetic A Indices
Observed Afr/Ap 08 Dec  001/002
Estimated Afr/Ap 09 Dec  036/055
Predicted Afr/Ap 10 Dec-12 Dec  013/009-007/009-011/014

VI.  Geomagnetic Activity Probabilities 10 Dec-12 Dec
A.  Middle Latitudes
Active                35/20/35
Minor Storm           35/05/10
Major-severe storm    20/01/01
B.  High Latitudes
Active                05/15/15
Minor Storm           20/25/30
Major-severe storm    75/25/45
