:Product: 0528RSGA.txt
:Issued: 2021 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 148 Issued at 2200Z on 28 May 2021

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 C7 event observed at
27/2315Z from Region 2824 (N20W55). There are currently 2 numbered
sunspot regions on the disk.
IB.  Solar Activity Forecast: Solar activity is likely to be low with a
slight chance for an M-class flare on day one (29 May) and expected to
be very low with a chance for a C-class flares on day two (30 May) and
expected to be very low with a slight chance for a C-class flare on day
three (31 May).

IIA.  Geophysical Activity Summary 27/2100Z to 28/2100Z: The geomagnetic
field has been at quiet levels for the past 24 hours. Solar wind speed
reached a peak of 455 km/s at 28/0257Z. Total IMF reached 8 nT at
28/0255Z. The maximum southward component of Bz reached -2 nT at
28/1611Z.  Electrons greater than 2 MeV at geosynchronous orbit reached
a peak level of 178 pfu.
IIB.  Geophysical Activity Forecast: The geomagnetic field is expected
to be at quiet levels on days one and three (29 May, 31 May) and quiet
to unsettled levels on day two (30 May).

III.  Event probabilities 29 May-31 May
Class M    10/05/01
Class X    01/01/01
Proton     01/01/01
PCAF       green

IV.  Penticton 10.7 cm Flux
Observed           28 May 077
Predicted   29 May-31 May 075/074/072
90 Day Mean        28 May 076

V.  Geomagnetic A Indices
Observed Afr/Ap 27 May  015/014
Estimated Afr/Ap 28 May  004/005
Predicted Afr/Ap 29 May-31 May  005/005-008/008-006/005

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