:Product: Report of Solar-Geophysical Activity
:Issued: 2026 Mar 21 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 80 Issued at 2200Z on 21 Mar 2026

IA.  Analysis of Solar Active Regions and Activity from 20/2100Z to
21/2100Z: Solar activity has been at low levels for the past 24 hours.
There are currently 4 numbered sunspot regions on the disk.
IB.  Solar Activity Forecast: Solar activity is expected to be very low
with a chance for a C-class flares and a slight chance for an M-class
flare on days one, two, and three (22 Mar, 23 Mar, 24 Mar).

IIA.  Geophysical Activity Summary 20/2100Z to 21/2100Z: The geomagnetic
field has been at unsettled to severe storm levels for the past 24
hours. Solar wind speed reached a peak of 569 km/s at 21/1147Z. Total
IMF reached 38 nT at 21/1532Z. The maximum southward component of Bz
reached -27 nT at 20/2105Z.  Electrons greater than 2 MeV at
geosynchronous orbit reached a peak level of 315 pfu.
IIB.  Geophysical Activity Forecast: The geomagnetic field is expected
to be at unsettled to major storm levels on day one (22 Mar), unsettled
to minor storm levels on day two (23 Mar) and quiet to active levels on
day three (24 Mar).

III.  Event probabilities 22 Mar-24 Mar
Class M    10/10/10
Class X    01/01/01
Proton     01/01/01
PCAF       green

IV.  Penticton 10.7 cm Flux
Observed           21 Mar 107
Predicted   22 Mar-24 Mar 108/108/105
90 Day Mean        21 Mar 141

V.  Geomagnetic A Indices
Observed Afr/Ap 20 Mar  025/034
Estimated Afr/Ap 21 Mar  033/060
Predicted Afr/Ap 22 Mar-24 Mar  023/036-020/025-013/014

VI.  Geomagnetic Activity Probabilities 22 Mar-24 Mar
A.  Middle Latitudes
Active                25/40/35
Minor Storm           40/30/15
Major-severe storm    25/05/01
B.  High Latitudes
Active                05/05/10
Minor Storm           15/25/25
Major-severe storm    79/65/50