:Product: 0913RSGA.txt
:Issued: 2024 Sep 13 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 257 Issued at 2200Z on 13 Sep 2024

IA.  Analysis of Solar Active Regions and Activity from 12/2100Z to
13/2100Z: Solar activity has been at high levels for the past 24 hours.
The largest solar event of the period was a M5 event observed at
13/0656Z from Region 3811 (S13W0*). 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 days one, two, and three
(14 Sep, 15 Sep, 16 Sep).

IIA.  Geophysical Activity Summary 12/2100Z to 13/2100Z: The geomagnetic
field has been at unsettled to minor storm levels for the past 24 hours.
Solar wind speed reached a peak of 619 km/s at 13/0104Z. Total IMF
reached 14 nT at 12/2102Z. The maximum southward component of Bz reached
-9 nT at 13/2015Z.  Electrons greater than 2 MeV at geosynchronous orbit
reached a peak level of 1135 pfu.
IIB.  Geophysical Activity Forecast: The geomagnetic field is expected
to be at unsettled to minor storm levels on days one and three (14 Sep,
16 Sep) and quiet to unsettled levels on day two (15 Sep). Protons have
a slight chance of crossing threshold on days one, two, and three (14
Sep, 15 Sep, 16 Sep).

III.  Event probabilities 14 Sep-16 Sep
Class M    55/55/55
Class X    10/10/10
Proton     10/10/10
PCAF       green

IV.  Penticton 10.7 cm Flux
Observed           13 Sep 186
Predicted   14 Sep-16 Sep 185/180/180
90 Day Mean        13 Sep 217

V.  Geomagnetic A Indices
Observed Afr/Ap 12 Sep  036/078
Estimated Afr/Ap 13 Sep  025/035
Predicted Afr/Ap 14 Sep-16 Sep  017/024-012/015-016/022

VI.  Geomagnetic Activity Probabilities 14 Sep-16 Sep
A.  Middle Latitudes
Active                40/30/40
Minor Storm           25/10/25
Major-severe storm    05/01/05
B.  High Latitudes
Active                10/15/10
Minor Storm           25/30/25
Major-severe storm    65/45/65