:Product: 0427RSGA.txt
:Issued: 2023 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 2023

IA.  Analysis of Solar Active Regions and Activity from 26/2100Z to
27/2100Z: Solar activity has been at moderate levels for the past 24
hours. The largest solar event of the period was a M1 event observed at
27/1114Z from Region 3288 (S23W07). 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 (28 Apr, 29 Apr,
30 Apr).

IIA.  Geophysical Activity Summary 26/2100Z to 27/2100Z: The geomagnetic
field has been at unsettled to active levels for the past 24 hours.
Solar wind speed reached a peak of 720 km/s at 27/0546Z. Total IMF
reached 8 nT at 26/2108Z. The maximum southward component of Bz reached
-7 nT at 27/1124Z.  Electrons greater than 2 MeV at geosynchronous orbit
reached a peak level of 3355 pfu.
IIB.  Geophysical Activity Forecast: The geomagnetic field is expected
to be at quiet to minor storm levels on day one (28 Apr) and quiet to
active levels on days two and three (29 Apr, 30 Apr).

III.  Event probabilities 28 Apr-30 Apr
Class M    25/25/25
Class X    01/01/01
Proton     05/05/05
PCAF       green

IV.  Penticton 10.7 cm Flux
Observed           27 Apr 141
Predicted   28 Apr-30 Apr 135/135/135
90 Day Mean        27 Apr 158

V.  Geomagnetic A Indices
Observed Afr/Ap 26 Apr  012/014
Estimated Afr/Ap 27 Apr  016/021
Predicted Afr/Ap 28 Apr-30 Apr  019/025-013/016-010/012

VI.  Geomagnetic Activity Probabilities 28 Apr-30 Apr
A.  Middle Latitudes
Active                35/25/25
Minor Storm           20/10/10
Major-severe storm    05/01/01
B.  High Latitudes
Active                15/15/15
Minor Storm           20/20/20
Major-severe storm    30/20/30