:Product: 0419RSGA.txt
:Issued: 2025 Apr 19 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 109 Issued at 2200Z on 19 Apr 2025

IA.  Analysis of Solar Active Regions and Activity from 18/2100Z to
19/2100Z: 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 (20 Apr, 21 Apr,
22 Apr).

IIA.  Geophysical Activity Summary 18/2100Z to 19/2100Z: The geomagnetic
field has been at quiet to active levels for the past 24 hours. Solar
wind speed reached a peak of 520 km/s at 19/0612Z. Total IMF reached 9
nT at 19/2100Z. The maximum southward component of Bz reached -8 nT at
19/2058Z.  Electrons greater than 2 MeV at geosynchronous orbit reached
a peak level of 456 pfu.
IIB.  Geophysical Activity Forecast: The geomagnetic field is expected
to be at quiet to active levels on days one and two (20 Apr, 21 Apr) and
quiet to major storm levels on day three (22 Apr).

III.  Event probabilities 20 Apr-22 Apr
Class M    40/40/40
Class X    05/05/05
Proton     01/01/01
PCAF       green

IV.  Penticton 10.7 cm Flux
Observed           19 Apr 157
Predicted   20 Apr-22 Apr 160/165/165
90 Day Mean        19 Apr 175

V.  Geomagnetic A Indices
Observed Afr/Ap 18 Apr  011/ 011
Estimated Afr/Ap 19 Apr  016/017
Predicted Afr/Ap 20 Apr-22 Apr  009/010-006/008-023/035

VI.  Geomagnetic Activity Probabilities 20 Apr-22 Apr
A.  Middle Latitudes
Active                30/15/35
Minor Storm           10/05/40
Major-severe storm    01/01/20
B.  High Latitudes
Active                15/15/05
Minor Storm           30/20/15
Major-severe storm    40/20/80