:Product: 0520RSGA.txt
:Issued: 2021 May 20 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 140 Issued at 2200Z on 20 May 2021

IA.  Analysis of Solar Active Regions and Activity from 19/2100Z to
20/2100Z: Solar activity has been at very low levels for the past 24
hours. There are currently 1 numbered sunspot regions on the disk.
IB.  Solar Activity Forecast: Solar activity is expected to be very low
with a slight chance for a C-class flare on day one (21 May) and
expected to be very low on days two and three (22 May, 23 May).

IIA.  Geophysical Activity Summary 19/2100Z to 20/2100Z: The geomagnetic
field has been at quiet to minor storm levels for the past 24 hours.
Solar wind speed reached a peak of 575 km/s at 20/2042Z. Total IMF
reached 18 nT at 20/1201Z. The maximum southward component of Bz reached
-14 nT at 20/1027Z.  Electrons greater than 2 MeV at geosynchronous
orbit reached a peak level of 117 pfu.
IIB.  Geophysical Activity Forecast: The geomagnetic field is expected
to be at quiet to active levels on day one (21 May), quiet to unsettled
levels on day two (22 May) and quiet levels on day three (23 May).

III.  Event probabilities 21 May-23 May
Class M    01/01/01
Class X    01/01/01
Proton     01/01/01
PCAF       green

IV.  Penticton 10.7 cm Flux
Observed           20 May 072
Predicted   21 May-23 May 072/072/072
90 Day Mean        20 May 076

V.  Geomagnetic A Indices
Observed Afr/Ap 19 May  005/005
Estimated Afr/Ap 20 May  020/024
Predicted Afr/Ap 21 May-23 May  008/010-008/008-006/005

VI.  Geomagnetic Activity Probabilities 21 May-23 May
A.  Middle Latitudes
Active                30/15/10
Minor Storm           10/01/01
Major-severe storm    01/01/01
B.  High Latitudes
Active                15/15/15
Minor Storm           30/25/20
Major-severe storm    40/20/20