:Product: 0427RSGA.txt
:Issued: 2025 Apr 27 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 117 Issued at 2200Z on 27 Apr 2025

IA.  Analysis of Solar Active Regions and Activity from 26/2100Z to
27/2100Z: Solar activity has been at low levels for the past 24 hours.
There are currently 9 numbered sunspot regions on the disk.
IB.  Solar Activity Forecast: Solar activity is expected to be low with
a slight chance for an M-class flare on days one, two, and three (28
Apr, 29 Apr, 30 Apr).

IIA.  Geophysical Activity Summary 26/2100Z to 27/2100Z: The geomagnetic
field has been at quiet levels for the past 24 hours. Solar wind speed
reached a peak of 536 km/s at 27/0710Z. Total IMF reached 10 nT at
27/1223Z. The maximum southward component of Bz reached -6 nT at
27/1618Z.  Electrons greater than 2 MeV at geosynchronous orbit reached
a peak level of 1439 pfu.
IIB.  Geophysical Activity Forecast: The geomagnetic field is expected
to be at quiet to active levels on day one (28 Apr), quiet to unsettled
levels on day two (29 Apr) and quiet levels on day three (30 Apr).

III.  Event probabilities 28 Apr-30 Apr
Class M    10/10/10
Class X    01/01/01
Proton     01/01/01
PCAF       green

IV.  Penticton 10.7 cm Flux
Observed           27 Apr 156
Predicted   28 Apr-30 Apr 150/145/140
90 Day Mean        27 Apr 171

V.  Geomagnetic A Indices
Observed Afr/Ap 26 Apr  007/007
Estimated Afr/Ap 27 Apr  007/008
Predicted Afr/Ap 28 Apr-30 Apr  011/010-007/008-006/005

VI.  Geomagnetic Activity Probabilities 28 Apr-30 Apr
A.  Middle Latitudes
Active                30/30/25
Minor Storm           15/15/10
Major-severe storm    01/01/01
B.  High Latitudes
Active                15/15/15
Minor Storm           30/30/25
Major-severe storm    45/45/35