:Product: 0518RSGA.txt
:Issued: 2023 May 18 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 138 Issued at 2200Z on 18 May 2023

IA.  Analysis of Solar Active Regions and Activity from 17/2100Z to
18/2100Z: Solar activity has been at moderate levels for the past 24
hours. The largest solar event of the period was a M2 event observed at
18/1147Z from Region 3311 (N18E76). There are currently 8 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 (19 May, 20 May,
21 May).

IIA.  Geophysical Activity Summary 17/2100Z to 18/2100Z: The geomagnetic
field has been at quiet levels for the past 24 hours. Solar wind speed
reached a peak of 501 km/s at 18/1058Z.  Electrons greater than 2 MeV at
geosynchronous orbit reached a peak level of 174 pfu.
IIB.  Geophysical Activity Forecast: The geomagnetic field is expected
to be at quiet levels on day one (19 May), quiet to unsettled levels on
day two (20 May) and quiet to active levels on day three (21 May).

III.  Event probabilities 19 May-21 May
Class M    35/25/25
Class X    05/05/05
Proton     01/01/01
PCAF       green

IV.  Penticton 10.7 cm Flux
Observed           18 May 151
Predicted   19 May-21 May 145/140/140
90 Day Mean        18 May 153

V.  Geomagnetic A Indices
Observed Afr/Ap 17 May  005/004
Estimated Afr/Ap 18 May  004/004
Predicted Afr/Ap 19 May-21 May  006/005-007/008-010/012

VI.  Geomagnetic Activity Probabilities 19 May-21 May
A.  Middle Latitudes
Active                10/20/25
Minor Storm           01/05/05
Major-severe storm    01/01/01
B.  High Latitudes
Active                15/15/15
Minor Storm           20/20/25
Major-severe storm    10/25/40