:Product: 0818RSGA.txt
:Issued: 2021 Aug 18 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 230 Issued at 2200Z on 18 Aug 2021

IA.  Analysis of Solar Active Regions and Activity from 17/2100Z to
18/2100Z: 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 days one, two, and three (19
Aug, 20 Aug, 21 Aug).

IIA.  Geophysical Activity Summary 17/2100Z to 18/2100Z: The geomagnetic
field has been at quiet to unsettled levels for the past 24 hours. Solar
wind speed reached a peak of 476 km/s at 17/2108Z.  Electrons greater
than 2 MeV at geosynchronous orbit reached a peak level of 490 pfu.
IIB.  Geophysical Activity Forecast: The geomagnetic field is expected
to be at quiet levels on days one and two (19 Aug, 20 Aug) and quiet to
unsettled levels on day three (21 Aug).

III.  Event probabilities 19 Aug-21 Aug
Class M    01/01/01
Class X    01/01/01
Proton     01/01/01
PCAF       green

IV.  Penticton 10.7 cm Flux
Observed           18 Aug 075
Predicted   19 Aug-21 Aug 075/075/073
90 Day Mean        18 Aug 079

V.  Geomagnetic A Indices
Observed Afr/Ap 17 Aug  007/004
Estimated Afr/Ap 18 Aug  005/006
Predicted Afr/Ap 19 Aug-21 Aug  005/005-005/005-008/008

VI.  Geomagnetic Activity Probabilities 19 Aug-21 Aug
A.  Middle Latitudes
Active                10/10/20
Minor Storm           01/01/05
Major-severe storm    01/01/01
B.  High Latitudes
Active                15/15/15
Minor Storm           20/20/30
Major-severe storm    15/15/25