:Product: 0816RSGA.txt
:Issued: 2026 Aug 16 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 228 Issued at 2200Z on 16 Aug 2026

IA.  Analysis of Solar Active Regions and Activity from 15/2100Z to
16/2100Z: Solar activity has been at low levels for the past 24 hours.
There are currently 5 numbered sunspot regions on the disk.
IB.  Solar Activity Forecast: Solar activity is expected to be low with
a slight chance for an M-class flare on days one, two, and three (17
Aug, 18 Aug, 19 Aug).

IIA.  Geophysical Activity Summary 15/2100Z to 16/2100Z: The geomagnetic
field has been at quiet levels for the past 24 hours. Solar wind
parameters were at background levels. Electrons greater than 2 MeV at
geosynchronous orbit reached a peak level of 395 pfu.
IIB.  Geophysical Activity Forecast: The geomagnetic field is expected
to be at quiet to active levels on days one and two (17 Aug, 18 Aug) and
quiet levels on day three (19 Aug).

III.  Event probabilities 17 Aug-19 Aug
Class M    15/15/15
Class X    01/01/01
Proton     01/01/01
PCAF       green

IV.  Penticton 10.7 cm Flux
Observed           16 Aug 129
Predicted   17 Aug-19 Aug 130/125/130
90 Day Mean        16 Aug 131

V.  Geomagnetic A Indices
Observed Afr/Ap 15 Aug  006/006
Estimated Afr/Ap 16 Aug  005/005
Predicted Afr/Ap 17 Aug-19 Aug  012/015-011/012-005/005

VI.  Geomagnetic Activity Probabilities 17 Aug-19 Aug
A.  Middle Latitudes
Active                15/10/10
Minor Storm           05/05/05
Major-severe storm    01/01/01
B.  High Latitudes
Active                20/20/20
Minor Storm           25/20/20
Major-severe storm    20/15/15