:Product: 0915RSGA.txt
:Issued: 2024 Sep 15 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 259 Issued at 2200Z on 15 Sep 2024

IA.  Analysis of Solar Active Regions and Activity from 14/2100Z to
15/2100Z: Solar activity has been at low levels for the past 24 hours.
The largest solar event of the period was a C4 event observed at
15/1528Z from Region 3824 (S04W26). There are currently 5 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 (16 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 (17 Sep, 18 Sep).

IIA.  Geophysical Activity Summary 14/2100Z to 15/2100Z: The geomagnetic
field has been at quiet to active levels for the past 24 hours. Solar
wind speed reached a peak of 523 km/s at 15/0323Z. Total IMF reached 9
nT at 14/2125Z. The maximum southward component of Bz reached -7 nT at
15/1548Z.  Protons greater than 10 MeV at geosynchronous orbit reached a
peak level of 6 pfu at 15/1455Z. Electrons greater than 2 MeV at
geosynchronous orbit reached a peak level of 1692 pfu.
IIB.  Geophysical Activity Forecast: The geomagnetic field is expected
to be at unsettled to severe storm levels on day one (16 Sep), quiet to
major storm levels on day two (17 Sep) and quiet to unsettled levels on
day three (18 Sep). Protons have a slight chance of crossing threshold
on day one (16 Sep), have a slight chance of crossing threshold on day
two (17 Sep) and have a slight chance of crossing threshold on day three
(18 Sep).

III.  Event probabilities 16 Sep-18 Sep
Class M    55/45/40
Class X    15/10/10
Proton     20/15/10
PCAF       green

IV.  Penticton 10.7 cm Flux
Observed           15 Sep 173
Predicted   16 Sep-18 Sep 175/170/170
90 Day Mean        15 Sep 217

V.  Geomagnetic A Indices
Observed Afr/Ap 14 Sep  022/023
Estimated Afr/Ap 15 Sep  017/020
Predicted Afr/Ap 16 Sep-18 Sep  045/070-019/028-007/010

VI.  Geomagnetic Activity Probabilities 16 Sep-18 Sep
A.  Middle Latitudes
Active                15/30/35
Minor Storm           35/35/20
Major-severe storm    50/25/05
B.  High Latitudes
Active                01/05/10
Minor Storm           10/15/30
Major-severe storm    90/80/55