:Product: 0423RSGA.txt
:Issued: 2023 Apr 23 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 113 Issued at 2200Z on 23 Apr 2023

IA.  Analysis of Solar Active Regions and Activity from 22/2100Z to
23/2100Z: Solar activity has been at low levels for the past 24 hours.
The largest solar event of the period was a C2 event observed at
23/0640Z from Region 3279 (S19W78). There are currently 6 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 day one (24 Apr) and likely to be low
with a chance for M-class flares on day two (25 Apr) and likely to be
low on day three (26 Apr).

IIA.  Geophysical Activity Summary 22/2100Z to 23/2100Z: The geomagnetic
field has been at quiet to severe storm levels for the past 24 hours.
Solar wind speed reached a peak of 733 km/s at 23/2057Z. Total IMF
reached 29 nT at 23/2054Z. The maximum southward component of Bz reached
-24 nT at 23/1710Z.  Protons greater than 10 MeV at geosynchronous orbit
reached a peak level of 26 pfu at 23/1820Z. Electrons greater than 2 MeV
at geosynchronous orbit reached a peak level of 157 pfu.
IIB.  Geophysical Activity Forecast: The geomagnetic field is expected
to be at unsettled to severe storm levels on day one (24 Apr), quiet to
active levels on day two (25 Apr) and quiet levels on day three (26
Apr). Protons greater than 10 Mev have a chance of crossing threshold on
day one (24 Apr) and have a slight chance of crossing threshold on day
two (25 Apr).

III.  Event probabilities 24 Apr-26 Apr
Class M    25/25/05
Class X    01/01/01
Proton     25/10/05
PCAF       green

IV.  Penticton 10.7 cm Flux
Observed           23 Apr 135
Predicted   24 Apr-26 Apr 135/130/125
90 Day Mean        23 Apr 159

V.  Geomagnetic A Indices
Observed Afr/Ap 22 Apr  006/007
Estimated Afr/Ap 23 Apr  039/069
Predicted Afr/Ap 24 Apr-26 Apr  032/047-013/015-007/008

VI.  Geomagnetic Activity Probabilities 24 Apr-26 Apr
A.  Middle Latitudes
Active                25/30/15
Minor Storm           35/15/05
Major-severe storm    35/01/01
B.  High Latitudes
Active                05/15/15
Minor Storm           20/30/20
Major-severe storm    79/45/20