773
FXXX02 KWNP 010156
WEKFOR

:Product: 27-day Space Weather Forecast
:Issued: 2025 Sep 01 0133 UTC
# Prepared by the US Dept. of Commerce, NOAA, Space Weather Prediction Center
# Product description and SWPC contact on the Web
# https://www.swpc.noaa.gov/content/subscription-services
#
#               27-day Space Weather Forecast
#
Forecast of Solar and Geomagnetic Activity
01 September - 27 September 2025

Solar activity is expected to be at low levels, with varying chances
for M-class flares (R1-R2/Minor-Moderate events) through 27 Sep.

The greater than 10 MeV proton flux levels are expected to be
slightly enhanced, but below the 10 pfu level for 01-03 Sep. There
is a chance levels could exceed the 10 pfu threshold on 01-02 Sep as
the halo CME from 30 Aug passes Earth. Conditions are then likely to
return to near background levels after 04 Sep, barring any
additional strong flare events.

The greater than 2 MeV electron flux at geosynchronous orbit is
expected to be at moderate levels on 01-02 Sep, 15-19 Sep, and 22-27
Sep. Flux levels are expected to reach high levels on 03-14 Sep and
20-21 Sep in association with coronal hole (CH) high speed stream
(HSS) influence.

Geomagnetic field activity is expected to reach G2 (Moderate)
geomagnetic storm levels on 01 Sep, G3 (Strong) levels on 02 Sep,
and active conditions on 03 Sep following the arrival of the halo
CME from 30 Aug. Active conditions are likely on 06-10 Sep, and
15-19 Sep with CH HSS influence. Quiet to unsettled levels are
expected on 04-05 Sep, 11-14 Sep, and 20-27 Sep.