:Product: 0827RSGA.txt
:Issued: 2021 Aug 27 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 239 Issued at 2200Z on 27 Aug 2021

IA.  Analysis of Solar Active Regions and Activity from 26/2100Z to
27/2100Z: Solar activity has been at low levels for the past 24 hours.
The largest solar event of the period was a C3 event observed at
26/2322Z from Region 2860 (S30E14). There are currently 4 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 days one, two, and three (28 Aug,
29 Aug, 30 Aug).

IIA.  Geophysical Activity Summary 26/2100Z to 27/2100Z: The geomagnetic
field has been at quiet to active levels for the past 24 hours. Solar
wind speed reached a peak of 525 km/s at 27/1906Z. Total IMF reached 16
nT at 27/1315Z. The maximum southward component of Bz reached -15 nT at
27/1847Z.  Electrons greater than 2 MeV at geosynchronous orbit reached
a peak level of 161 pfu.
IIB.  Geophysical Activity Forecast: The geomagnetic field is expected
to be at quiet to minor storm levels on days one, two, and three (28
Aug, 29 Aug, 30 Aug).

III.  Event probabilities 28 Aug-30 Aug
Class M    15/15/15
Class X    01/01/01
Proton     01/01/01
PCAF       green

IV.  Penticton 10.7 cm Flux
Observed           27 Aug 090
Predicted   28 Aug-30 Aug 090/090/090
90 Day Mean        27 Aug 079

V.  Geomagnetic A Indices
Observed Afr/Ap 26 Aug  006/006
Estimated Afr/Ap 27 Aug  018/022
Predicted Afr/Ap 28 Aug-30 Aug  012/015-011/018-022/025

VI.  Geomagnetic Activity Probabilities 28 Aug-30 Aug
A.  Middle Latitudes
Active                40/35/30
Minor Storm           25/35/40
Major-severe storm    05/20/25
B.  High Latitudes
Active                10/05/05
Minor Storm           20/20/15
Major-severe storm    65/75/80