:Product: Report of Solar-Geophysical Activity
:Issued: 2026 Jan 20 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 20 Issued at 2200Z on 20 Jan 2026

IA.  Analysis of Solar Active Regions and Activity from 19/2100Z to
20/2100Z: Solar activity has been at low levels for the past 24 hours.
There are currently 11 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
(21 Jan, 22 Jan, 23 Jan).

IIA.  Geophysical Activity Summary 19/2100Z to 20/2100Z: The geomagnetic
field has been at major storm to severe storm levels for the past 24
hours. Solar wind speed reached a peak of 1178 km/s at 19/2133Z. Total
IMF reached 91 nT at 19/2124Z. The maximum southward component of Bz
reached -58 nT at 19/2104Z.  Protons greater than 10 MeV at
geosynchronous orbit reached a peak level of 5680 pfu at 19/2110Z.
Electrons greater than 2 MeV at geosynchronous orbit reached a peak
level of 720 pfu.
IIB.  Geophysical Activity Forecast: The geomagnetic field is expected
to be at unsettled to severe storm levels on day one (21 Jan), unsettled
to active levels on day two (22 Jan) and quiet to unsettled levels on
day three (23 Jan). Protons are expected to cross threshold on day one
(21 Jan), have a chance of crossing threshold on day two (22 Jan) and
have a slight chance of crossing threshold on day three (23 Jan).

III.  Event probabilities 21 Jan-23 Jan
Class M    60/60/60
Class X    15/15/15
Proton     99/45/15
PCAF       red

IV.  Penticton 10.7 cm Flux
Observed           20 Jan 178
Predicted   21 Jan-23 Jan 180/180/175
90 Day Mean        20 Jan 147

V.  Geomagnetic A Indices
Observed Afr/Ap 19 Jan  064/073
Estimated Afr/Ap 20 Jan  068/125
Predicted Afr/Ap 21 Jan-23 Jan  025/042-016/018-008/010

VI.  Geomagnetic Activity Probabilities 21 Jan-23 Jan
A.  Middle Latitudes
Active                15/35/20
Minor Storm           35/15/05
Major-severe storm    50/05/01
B.  High Latitudes
Active                01/10/15
Minor Storm           10/30/25
Major-severe storm    90/50/25