:Product: 0528RSGA.txt
:Issued: 2024 May 28 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 149 Issued at 2200Z on 28 May 2024

IA.  Analysis of Solar Active Regions and Activity from 27/2100Z to
28/2100Z: Solar activity has been at low levels for the past 24 hours.
The largest solar event of the period was a C8 event observed at
28/1841Z from Region 3697 (S18E69). 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 (29 May, 30
May, 31 May).

IIA.  Geophysical Activity Summary 27/2100Z to 28/2100Z: The geomagnetic
field has been at quiet to unsettled levels for the past 24 hours. Solar
wind speed reached a peak of 389 km/s at 27/2307Z. Total IMF reached 7
nT at 28/1906Z. The maximum southward component of Bz reached -4 nT at
27/2206Z.  Electrons greater than 2 MeV at geosynchronous orbit reached
a peak level of 327 pfu.
IIB.  Geophysical Activity Forecast: The geomagnetic field is expected
to be at quiet to active levels on day one (29 May), quiet to unsettled
levels on day two (30 May) and quiet levels on day three (31 May).
Protons have a slight chance of crossing threshold on days one, two, and
three (29 May, 30 May, 31 May).

III.  Event probabilities 29 May-31 May
Class M    60/60/60
Class X    30/30/30
Proton     10/10/10
PCAF       green

IV.  Penticton 10.7 cm Flux
Observed           28 May 166
Predicted   29 May-31 May 170/170/175
90 Day Mean        28 May 168

V.  Geomagnetic A Indices
Observed Afr/Ap 27 May  009/009
Estimated Afr/Ap 28 May  007/008
Predicted Afr/Ap 29 May-31 May  009/012-009/008-006/005

VI.  Geomagnetic Activity Probabilities 29 May-31 May
A.  Middle Latitudes
Active                35/20/10
Minor Storm           15/05/01
Major-severe storm    01/01/01
B.  High Latitudes
Active                10/15/15
Minor Storm           30/30/20
Major-severe storm    50/25/20