:Product: 1018RSGA.txt
:Issued: 2025 Oct 18 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 291 Issued at 2200Z on 18 Oct 2025

IA.  Analysis of Solar Active Regions and Activity from 17/2100Z to
18/2100Z: Solar activity has been at high levels for the past 24 hours.
There are currently 7 numbered sunspot regions on the disk.
IB.  Solar Activity Forecast: Solar activity is expected to be low with
a chance for M-class flares on days one, two, and three (19 Oct, 20 Oct,
21 Oct).

IIA.  Geophysical Activity Summary 17/2100Z to 18/2100Z: The geomagnetic
field has been at quiet to major storm levels for the past 24 hours.
Solar wind speed reached a peak of 587 km/s at 18/1439Z. Total IMF
reached 20 nT at 18/0822Z. The maximum southward component of Bz reached
-12 nT at 18/0953Z.  Electrons greater than 2 MeV at geosynchronous
orbit reached a peak level of 700 pfu.
IIB.  Geophysical Activity Forecast: The geomagnetic field is expected
to be at quiet to active levels on days one and two (19 Oct, 20 Oct) and
quiet to unsettled levels on day three (21 Oct).

III.  Event probabilities 19 Oct-21 Oct
Class M    35/35/35
Class X    05/05/05
Proton     01/01/01
PCAF       green

IV.  Penticton 10.7 cm Flux
Observed           18 Oct 156
Predicted   19 Oct-21 Oct 150/155/160
90 Day Mean        18 Oct 154

V.  Geomagnetic A Indices
Observed Afr/Ap 17 Oct  008/009
Estimated Afr/Ap 18 Oct  023/033
Predicted Afr/Ap 19 Oct-21 Oct  013/015-011/012-008/008

VI.  Geomagnetic Activity Probabilities 19 Oct-21 Oct
A.  Middle Latitudes
Active                30/30/20
Minor Storm           15/15/05
Major-severe storm    05/05/01
B.  High Latitudes
Active                10/10/15
Minor Storm           25/25/25
Major-severe storm    50/50/25
