368
FXXX12 KWNP 031231
DAYDIS

:Product: Forecast Discussion
:Issued: 2025 Oct 03 1230 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 remained at moderate levels during the past 24h due to an
M1.5/2n double-peak flare with flare peak occurring on Oct 03/0523 UTC
from Region 4236 (N10W29, Dhc/beta-gamma). This M-flare raised the
background X-ray levels (from C1.5 to C2.5) and was associated with a
filament disruption (observed at GONG/H-alpha imagery) that included an
ejected component resulting in a faint CME first observed by LASCO/C2
coronagraph imagery at 03/0648 UTC. Modeling of this event is currently
underway.

Two new active regions were numbered during this period: Region 4242
(S11E27, Cro/beta) and Region 4243 (N18E55, Bxo/beta). With them, a
total of 10 regions were present at the visible solar disk in the past
24h.

Additional activity included a type II radio sweep with an estimated
speed of 1,618 km/s and a type IV emission beginning at 03/1112 UTC.
Early analysis of GOES-19 SUVI imagery suggests related field line
movement originating just beyond the western limb to be the culprit.
Additional analysis of a subsequent CME will be performed as coronagraph
imagery becomes available, but given the source region an Earth-directed
component is unlikely.

.Forecast...
Solar flare activity is likely to remain at low to moderate levels
(R1-R2), with a slight chance (10%) for strong (R3) events through 04
Oct. Considering the imminent exit of the regions 4238 (S14W84,
Cso/beta) and 4230 (S10W80, Eai/beta-gamma), the M-flare probabilities
for the upcoming two days (Oct 04-05) are considered slightly reduced.

Energetic Particle

.24 hr Summary...
The greater than 2 MeV electron flux remained high (above 1,000 pfu) for
the most part of the period, peaking at Oct 03/0605 UTC with 7,010 pfu,
due to magnetospheric responses to persistent high speed streams (HSS)
associated with a positive polarity coronal hole (CH). The greater than
10 MeV proton fluxes measured by GOES-R satellites remained at
background levels during the past 24h.

.Forecast...
The greater than 2 MeV electron flux is expected to remain at high
levels as the CH HSS continues to be geoeffective in the next three
days. The greater than 10 MeV proton flux is expected to continue at
background level over the next few days, with a low (5%) chance for a
proton event, due to the presence of magnetically complex growing active
regions.

Solar Wind

.24 hr Summary...
The solar wind near Earth continued to be dominated by CH HSS
conditions, with Phi angle values representative of the positive sector
and speeds varying between 700-800 km/s during the period. The total
Interplanetary Magnetic Field (Bt) remained oscillating around 5 nT,
with north/south (Bz) component between -/+ 5 nT.

.Forecast...
The CH HSS influences on the solar wind conditions near Earth are
expected to persist through 05 Oct, as the planet continues to be
embedded at the CH associated co-rotating interactive region (CIR). A
recurrent negative CH was observed rotating into the East limb of the
visible solar disk during the period, but no impact is expected from it
in the upcoming days.

Geospace

.24 hr Summary...
The geomagnetic activity was active for most part of the period,
reaching G1 (Minor) storming levels during the following synoptic
periods: 02/18-21, 03/03-06 and 03/06-09. That was due to the influence
of the ongoing CIR/HSS near Earths environment.

.Forecast...
G1 (Minor) geomagnetic activity levels are expected until 03/1500 UTC,
with primarily unsettled to active conditions persisting through 05 Oct.