:Product: 0911RSGA.txt
:Issued: 2024 Sep 11 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 255 Issued at 2200Z on 11 Sep 2024

IA.  Analysis of Solar Active Regions and Activity from 10/2100Z to
11/2100Z: Solar activity has been at high levels for the past 24 hours.
The largest solar event of the period was a M2 event observed at
11/1752Z from Region 3814 (N15W16). There are currently 10 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
(12 Sep, 13 Sep, 14 Sep).

IIA.  Geophysical Activity Summary 10/2100Z to 11/2100Z: The geomagnetic
field has been at quiet to unsettled levels for the past 24 hours. Solar
wind speed reached a peak of 422 km/s at 10/2120Z. Total IMF reached 11
nT at 11/1729Z. The maximum southward component of Bz reached -6 nT at
11/1959Z.  Electrons greater than 2 MeV at geosynchronous orbit reached
a peak level of 192 pfu.
IIB.  Geophysical Activity Forecast: The geomagnetic field is expected
to be at quiet to minor storm levels on day one (12 Sep), quiet to major
storm levels on day two (13 Sep) and unsettled to active levels on day
three (14 Sep). Protons have a slight chance of crossing threshold on
days one, two, and three (12 Sep, 13 Sep, 14 Sep).

III.  Event probabilities 12 Sep-14 Sep
Class M    55/55/55
Class X    15/15/15
Proton     15/15/15
PCAF       green

IV.  Penticton 10.7 cm Flux
Observed           11 Sep 207
Predicted   12 Sep-14 Sep 200/200/200
90 Day Mean        11 Sep 217

V.  Geomagnetic A Indices
Observed Afr/Ap 10 Sep  007/006
Estimated Afr/Ap 11 Sep  012/016
Predicted Afr/Ap 12 Sep-14 Sep  012/025-023/035-017/025

VI.  Geomagnetic Activity Probabilities 12 Sep-14 Sep
A.  Middle Latitudes
Active                35/30/35
Minor Storm           25/35/25
Major-severe storm    05/20/05
B.  High Latitudes
Active                10/05/10
Minor Storm           20/20/20
Major-severe storm    65/75/60