:Product: 0428RSGA.txt
:Issued: 2023 Apr 28 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 118 Issued at 2200Z on 28 Apr 2023

IA.  Analysis of Solar Active Regions and Activity from 27/2100Z to
28/2100Z: Solar activity has been at low levels for the past 24 hours.
The largest solar event of the period was a C6 event observed at
28/1600Z from Region 3289 (N20E37). There are currently 6 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 (29 Apr, 30 Apr,
01 May).

IIA.  Geophysical Activity Summary 27/2100Z to 28/2100Z: The geomagnetic
field has been at unsettled to active levels for the past 24 hours.
Solar wind speed reached a peak of 740 km/s at 28/1322Z. Total IMF
reached 5 nT at 28/0751Z. The maximum southward component of Bz reached
-5 nT at 27/2255Z.  Electrons greater than 2 MeV at geosynchronous orbit
reached a peak level of 5965 pfu.
IIB.  Geophysical Activity Forecast: The geomagnetic field is expected
to be at quiet to active levels on days one and two (29 Apr, 30 Apr) and
quiet to unsettled levels on day three (01 May).

III.  Event probabilities 29 Apr-01 May
Class M    25/25/25
Class X    01/01/01
Proton     05/05/05
PCAF       green

IV.  Penticton 10.7 cm Flux
Observed           28 Apr 150
Predicted   29 Apr-01 May 145/145/145
90 Day Mean        28 Apr 158

V.  Geomagnetic A Indices
Observed Afr/Ap 27 Apr  020/025
Estimated Afr/Ap 28 Apr  018/022
Predicted Afr/Ap 29 Apr-01 May  013/016-010/012-008/012

VI.  Geomagnetic Activity Probabilities 29 Apr-01 May
A.  Middle Latitudes
Active                25/25/15
Minor Storm           10/10/05
Major-severe storm    01/01/01
B.  High Latitudes
Active                15/15/15
Minor Storm           20/20/15
Major-severe storm    20/30/15