:Product: 0519RSGA.txt
:Issued: 2023 May 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 139 Issued at 2200Z on 19 May 2023

IA.  Analysis of Solar Active Regions and Activity from 18/2100Z to
19/2100Z: Solar activity has been at high levels for the past 24 hours.
The largest solar event of the period was a M5 event observed at
19/0048Z from Region 3311 (N17E60). There are currently 9 numbered
sunspot regions on the disk.
IB.  Solar Activity Forecast: Solar activity is likely to be moderate
with a chance for X-class flares on days one, two, and three (20 May, 21
May, 22 May).

IIA.  Geophysical Activity Summary 18/2100Z to 19/2100Z: The geomagnetic
field has been at quiet to unsettled levels for the past 24 hours. Solar
wind speed reached a peak of 373 km/s at 19/2059Z. Total IMF reached 12
nT at 19/2100Z. The maximum southward component of Bz reached -8 nT at
19/2038Z.  Electrons greater than 2 MeV at geosynchronous orbit reached
a peak level of 318 pfu.
IIB.  Geophysical Activity Forecast: The geomagnetic field is expected
to be at quiet to active levels on days one and two (20 May, 21 May) and
quiet to unsettled levels on day three (22 May). Protons have a slight
chance of crossing threshold on days one, two, and three (20 May, 21
May, 22 May).

III.  Event probabilities 20 May-22 May
Class M    55/55/55
Class X    25/25/25
Proton     10/10/10
PCAF       green

IV.  Penticton 10.7 cm Flux
Observed           19 May 165
Predicted   20 May-22 May 165/165/160
90 Day Mean        19 May 153

V.  Geomagnetic A Indices
Observed Afr/Ap 18 May  008/004
Estimated Afr/Ap 19 May  005/008
Predicted Afr/Ap 20 May-22 May  009/010-010/012-010/010

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