:Product: 0819RSGA.txt
:Issued: 2025 Aug 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 231 Issued at 2200Z on 19 Aug 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 3 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 (20 Aug, 21 Aug, 22 Aug).

IIA.  Geophysical Activity Summary 18/2100Z to 19/2100Z: The geomagnetic
field has been at quiet to minor storm levels for the past 24 hours.
Solar wind speed reached a peak of 707 km/s at 19/1521Z. Total IMF
reached 19 nT at 19/1231Z. The maximum southward component of Bz reached
-11 nT at 19/1636Z.  Electrons greater than 2 MeV at geosynchronous
orbit reached a peak level of 471 pfu.
IIB.  Geophysical Activity Forecast: The geomagnetic field is expected
to be at unsettled to minor storm levels on day one (20 Aug), quiet to
active levels on day two (21 Aug) and quiet levels on day three (22
Aug).

III.  Event probabilities 20 Aug-22 Aug
Class M    10/10/10
Class X    01/01/01
Proton     01/01/01
PCAF       green

IV.  Penticton 10.7 cm Flux
Observed           19 Aug 116
Predicted   20 Aug-22 Aug 115/115/115
90 Day Mean        19 Aug 136

V.  Geomagnetic A Indices
Observed Afr/Ap 18 Aug  005/ 007
Estimated Afr/Ap 19 Aug  015/021
Predicted Afr/Ap 20 Aug-22 Aug  018/025-012/015-007/008

VI.  Geomagnetic Activity Probabilities 20 Aug-22 Aug
A.  Middle Latitudes
Active                35/30/20
Minor Storm           30/15/05
Major-severe storm    10/01/01
B.  High Latitudes
Active                05/15/15
Minor Storm           20/30/30
Major-severe storm    70/40/25
