:Product: 1230RSGA.txt
:Issued: 2025 Dec 30 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 364 Issued at 2200Z on 30 Dec 2025

IA.  Analysis of Solar Active Regions and Activity from 29/2100Z to
30/2100Z: Solar activity has been at low levels for the past 24 hours.
There are currently 9 numbered sunspot regions on the disk.
IB.  Solar Activity Forecast: Solar activity is likely to be moderate
with a chance for X-class flares on days one, two, and three (31 Dec, 01
Jan, 02 Jan).

IIA.  Geophysical Activity Summary 29/2100Z to 30/2100Z: The geomagnetic
field has been at quiet to unsettled levels for the past 24 hours. Solar
wind speed reached a peak of 563 km/s at 30/1514Z. Total IMF reached 9
nT at 30/1503Z. The maximum southward component of Bz reached -6 nT at
30/1515Z.  Electrons greater than 2 MeV at geosynchronous orbit reached
a peak level of 5,612 pfu.
IIB.  Geophysical Activity Forecast: The geomagnetic field is expected
to be at quiet to active levels on day one (31 Dec), unsettled to minor
storm levels on day two (01 Jan) and unsettled to active levels on day
three (02 Jan). Protons have a slight chance of crossing threshold on
days one, two, and three (31 Dec, 01 Jan, 02 Jan).

III.  Event probabilities 31 Dec-02 Jan
Class M    60/60/60
Class X    25/25/25
Proton     15/15/15
PCAF       green

IV.  Penticton 10.7 cm Flux
Observed           30 Dec 182
Predicted   31 Dec-02 Jan 200/200/195
90 Day Mean        30 Dec 146

V.  Geomagnetic A Indices
Observed Afr/Ap 29 Dec  009/009
Estimated Afr/Ap 30 Dec  008/009
Predicted Afr/Ap 31 Dec-02 Jan  011/012-021/029-013/018

VI.  Geomagnetic Activity Probabilities 31 Dec-02 Jan
A.  Middle Latitudes
Active                30/45/35
Minor Storm           10/25/15
Major-severe storm    01/05/01
B.  High Latitudes
Active                15/10/15
Minor Storm           30/25/30
Major-severe storm    40/70/45
