:Product: 0420RSGA.txt
:Issued: 2025 Apr 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 110 Issued at 2200Z on 20 Apr 2025

IA.  Analysis of Solar Active Regions and Activity from 19/2100Z to
20/2100Z: Solar activity has been at moderate levels for the past 24
hours. There are currently 7 numbered sunspot regions on the disk.
IB.  Solar Activity Forecast: Solar activity is expected to be low with
a chance for M-class flares on days one, two, and three (21 Apr, 22 Apr,
23 Apr).

IIA.  Geophysical Activity Summary 19/2100Z to 20/2100Z: The geomagnetic
field has been at quiet to minor storm levels for the past 24 hours.
Solar wind speed reached a peak of 455 km/s at 20/0206Z. Total IMF
reached 13 nT at 20/1930Z. The maximum southward component of Bz reached
-9 nT at 20/1901Z.  Electrons greater than 2 MeV at geosynchronous orbit
reached a peak level of 801 pfu.
IIB.  Geophysical Activity Forecast: The geomagnetic field is expected
to be at quiet to active levels on day one (21 Apr), quiet to major
storm levels on day two (22 Apr) and unsettled to major storm levels on
day three (23 Apr).

III.  Event probabilities 21 Apr-23 Apr
Class M    40/40/40
Class X    05/05/05
Proton     01/01/01
PCAF       green

IV.  Penticton 10.7 cm Flux
Observed           20 Apr 156
Predicted   21 Apr-23 Apr 160/165/165
90 Day Mean        20 Apr 174

V.  Geomagnetic A Indices
Observed Afr/Ap 19 Apr  018/018
Estimated Afr/Ap 20 Apr  014/014
Predicted Afr/Ap 21 Apr-23 Apr  010/012-023/035-024/035

VI.  Geomagnetic Activity Probabilities 21 Apr-23 Apr
A.  Middle Latitudes
Active                15/35/35
Minor Storm           05/40/40
Major-severe storm    01/20/15
B.  High Latitudes
Active                15/05/05
Minor Storm           20/15/20
Major-severe storm    20/80/75
