:Product: 0523RSGA.txt
:Issued: 2023 May 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 143 Issued at 2200Z on 23 May 2023

IA.  Analysis of Solar Active Regions and Activity from 22/2100Z to
23/2100Z: Solar activity has been at moderate levels for the past 24
hours. The largest solar event of the period was a M3 event observed at
23/1213Z from Region 3311 (N18E05). 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 and a slight chance for an X-class flare on
days one and two (24 May, 25 May) and likely to be moderate with a
slight chance for an X-class flare on day three (26 May).

IIA.  Geophysical Activity Summary 22/2100Z to 23/2100Z: The geomagnetic
field has been at quiet to active levels for the past 24 hours. Solar
wind speed reached a peak of 626 km/s at 23/0257Z. Total IMF reached 9
nT at 23/0104Z. The maximum southward component of Bz reached -7 nT at
23/0313Z.  Electrons greater than 2 MeV at geosynchronous orbit reached
a peak level of 1236 pfu.
IIB.  Geophysical Activity Forecast: The geomagnetic field is expected
to be at quiet to minor storm levels on day one (24 May) and quiet to
active levels on days two and three (25 May, 26 May). Protons have a
slight chance of crossing threshold on days one and two (24 May, 25 May)
and have a slight chance of crossing threshold on day three (26 May).

III.  Event probabilities 24 May-26 May
Class M    50/50/55
Class X    10/10/15
Proton     10/10/15
PCAF       green

IV.  Penticton 10.7 cm Flux
Observed           23 May 155
Predicted   24 May-26 May 155/155/160
90 Day Mean        23 May 153

V.  Geomagnetic A Indices
Observed Afr/Ap 22 May  017/023
Estimated Afr/Ap 23 May  011/015
Predicted Afr/Ap 24 May-26 May  019/021-011/015-014/016

VI.  Geomagnetic Activity Probabilities 24 May-26 May
A.  Middle Latitudes
Active                35/35/35
Minor Storm           30/20/15
Major-severe storm    10/05/01
B.  High Latitudes
Active                15/20/10
Minor Storm           25/30/30
Major-severe storm    50/30/50