:Product: 0821RSGA.txt
:Issued: 2021 Aug 21 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 233 Issued at 2200Z on 21 Aug 2021

IA.  Analysis of Solar Active Regions and Activity from 20/2100Z to
21/2100Z: Solar activity has been at low levels for the past 24 hours.
The largest solar event of the period was a C1 event observed at
20/2200Z from new Region 2859. There are currently 2 numbered sunspot
regions on the disk.
IB.  Solar Activity Forecast: Solar activity is expected to be very low
with a chance for a C-class flares on days one, two, and three (22 Aug,
23 Aug, 24 Aug).

IIA.  Geophysical Activity Summary 20/2100Z to 21/2100Z: The geomagnetic
field has been at quiet levels for the past 24 hours. Solar wind speed
reached a peak of 356 km/s at 21/0832Z. Total IMF reached 7 nT at
21/0439Z. The maximum southward component of Bz reached -3 nT at
21/1314Z.  Electrons greater than 2 MeV at geosynchronous orbit reached
a peak level of 154 pfu.
IIB.  Geophysical Activity Forecast: The geomagnetic field is expected
to be at quiet to unsettled levels on days one and two (22 Aug, 23 Aug)
and quiet to active levels on day three (24 Aug).

III.  Event probabilities 22 Aug-24 Aug
Class M    05/05/05
Class X    01/01/01
Proton     01/01/01
PCAF       green

IV.  Penticton 10.7 cm Flux
Observed           21 Aug 077
Predicted   22 Aug-24 Aug 077/077/077
90 Day Mean        21 Aug 079

V.  Geomagnetic A Indices
Observed Afr/Ap 20 Aug  006/007
Estimated Afr/Ap 21 Aug  004/005
Predicted Afr/Ap 22 Aug-24 Aug  008/008-008/010-011/014

VI.  Geomagnetic Activity Probabilities 22 Aug-24 Aug
A.  Middle Latitudes
Active                20/20/40
Minor Storm           05/05/15
Major-severe storm    01/01/01
B.  High Latitudes
Active                15/15/10
Minor Storm           30/30/30
Major-severe storm    25/25/55