:Product: 0916RSGA.txt
:Issued: 2024 Sep 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 260 Issued at 2200Z on 16 Sep 2024

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.
The largest solar event of the period was a C5 event observed at
16/0125Z from Region 3824 (S04W40). There are currently 7 numbered
sunspot regions on the disk.
IB.  Solar Activity Forecast: Solar activity is likely to be moderate
with a slight chance for an X-class flare on day one (17 Sep) and
expected to be low with a chance for M-class flares and a slight chance
for an X-class flare on days two and three (18 Sep, 19 Sep).

IIA.  Geophysical Activity Summary 15/2100Z to 16/2100Z: The geomagnetic
field has been at quiet to active levels for the past 24 hours. Solar
wind speed reached a peak of 580 km/s at 16/0606Z. Total IMF reached 10
nT at 16/0947Z. The maximum southward component of Bz reached -9 nT at
16/0932Z.  Protons greater than 10 MeV at geosynchronous orbit reached a
peak level of 4 pfu at 15/2150Z. Electrons greater than 2 MeV at
geosynchronous orbit reached a peak level of 2241 pfu.
IIB.  Geophysical Activity Forecast: The geomagnetic field is expected
to be at quiet to major storm levels on day one (17 Sep) and quiet to
unsettled levels on days two and three (18 Sep, 19 Sep). Protons have a
slight chance of crossing threshold on day one (17 Sep), have a slight
chance of crossing threshold on day two (18 Sep) and have a slight
chance of crossing threshold on day three (19 Sep).

III.  Event probabilities 17 Sep-19 Sep
Class M    55/45/40
Class X    15/10/10
Proton     20/15/10
PCAF       green

IV.  Penticton 10.7 cm Flux
Observed           16 Sep 170
Predicted   17 Sep-19 Sep 170/170/170
90 Day Mean        16 Sep 217

V.  Geomagnetic A Indices
Observed Afr/Ap 15 Sep  016/020
Estimated Afr/Ap 16 Sep  022/027
Predicted Afr/Ap 17 Sep-19 Sep  019/028-007/010-007/008

VI.  Geomagnetic Activity Probabilities 17 Sep-19 Sep
A.  Middle Latitudes
Active                30/30/20
Minor Storm           35/15/05
Major-severe storm    25/05/01
B.  High Latitudes
Active                05/15/15
Minor Storm           15/30/20
Major-severe storm    80/50/25