771
FXXX12 KWNP 010031
DAYDIS

:Product: Forecast Discussion
:Issued: 2025 Sep 01 0030 UTC
# Prepared by the US Dept. of Commerce, NOAA, Space Weather Prediction Center
# Product description and SWPC contact on the Web
# http://www.swpc.noaa.gov/wwire.html
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#             Forecast Discussion
#
Solar Activity

.24 hr Summary...
Solar activity decreased from moderate to low levels. Region 4202
(S15W05, Hax/alpha) produced a C6.8 flare at 31/1826 UTC. Region 4197
(S18W24, Ekc/beta-gamma) remained the largest spot group on the disk,
but only produced a few C-class flares. This region was mostly stable
with some minor decay noted in the intermediate spot area with the loss
of the delta configuration in the intermediate portion. Region 4191
(N11W68, Cho/beta) also produced C-class flare activity. Little change
was noticed in this region.

Region 4207 (N30E58, Eao/beta) developed additional trailer spots.
However, due to foreshortening, it is difficult to discern whether or
not these additional spots are part of a new, separate region. New
Region 4208 (N18W68, Dro/beta) was numbered. The remaining regions were
stable.

An asymmetric full-halo CME, associated with the long-duration M2.7
flare at 30/2002 UTC from AR4199, was first observed in LASCO C3 imagery
at ~30/2030 UTC. Analysis suggests this CME will arrive during the
latter half of 01 Sep.

.Forecast...
M-class flares (R1-R2/Minor-Moderate) are likely, with a slight chance
for an X-class flare (R3-Strong or greater), through 03 Sep.

Energetic Particle

.24 hr Summary...
The greater than 2 MeV electron flux was at normal to moderate levels.
The greater than 10 MeV proton flux remained elevated but below S1
(Minor) storm levels.

.Forecast...
The greater than 2 MeV electron flux is expected to be at normal to
moderate levels over 01-02 Sep, with moderate to high levels likely on
03 Sep. There is a slight chance for the greater than 10 MeV proton flux
to reach S1 (Minor) storm levels through 03 Sep.

Solar Wind

.24 hr Summary...
Nominal solar wind conditions prevailed throughout the period. Total
magnetic field strength peaked at 10 nT and the Bz component varied
between +9/-7 nT. Solar wind speed began to increase from a low of ~375
km/s to a peak of near 500 km/s after 31/0230 UTC. The phi orientation
was predominately negative.

.Forecast...
Mildly enhanced conditions are expected for most of 01 Sep under
negative polarity CH HSS influences. Stronger enhancements are likely
late on 01 Sep through most of 02 Sep with the anticipated arrival of
the 30 Aug asymmetric full-halo CME. Enhanced conditions are likely to
continue on 03 Sep.

Geospace

.24 hr Summary...
The geomagnetic field was at quiet levels.

.Forecast...
The geomagnetic field is expected to be at quiet to unsettled levels on
01 Sep under negative polarity CH HSS influences. Periods of G2
(Moderate) storming are likely, with a chance for G3 (Strong) storm
periods, late on 01 Sep due to the anticipated arrival of the 30 Aug
asymmetric full halo CME. On 02 Sep, periods of G3 (Strong) storming
are likely, with a chance for G4 (Severe) storm periods, as CME
influences continue. As CME effects weaken, unsettled to active
conditions are likely on 03 Sep.