:Product: 0417RSGA.txt
:Issued: 2022 Apr 17 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 107 Issued at 2200Z on 17 Apr 2022

IA.  Analysis of Solar Active Regions and Activity from 16/2100Z to
17/2100Z: Solar activity has been at high levels for the past 24 hours.
The largest solar event of the period was a X1 event observed at
17/0334Z from Region 2994 (N13E66). There are currently 5 numbered
sunspot regions on the disk.
IB.  Solar Activity Forecast: Solar activity is expected to be moderate
with a chance for X-class flares on days one, two, and three (18 Apr, 19
Apr, 20 Apr).

IIA.  Geophysical Activity Summary 16/2100Z to 17/2100Z: The geomagnetic
field has been at quiet to unsettled levels for the past 24 hours. Solar
wind speed reached a peak of 593 km/s at 16/2256Z. Total IMF reached 10
nT at 17/2038Z. The maximum southward component of Bz reached -7 nT at
17/1354Z.  Electrons greater than 2 MeV at geosynchronous orbit reached
a peak level of 2314 pfu.
IIB.  Geophysical Activity Forecast: The geomagnetic field is expected
to be at quiet to active levels on day one (18 Apr) and quiet to
unsettled levels on days two and three (19 Apr, 20 Apr).

III.  Event probabilities 18 Apr-20 Apr
Class M    75/75/75
Class X    25/25/25
Proton     05/05/05
PCAF       green

IV.  Penticton 10.7 cm Flux
Observed           17 Apr 135
Predicted   18 Apr-20 Apr 135/130/130
90 Day Mean        17 Apr 113

V.  Geomagnetic A Indices
Observed Afr/Ap 16 Apr  007/006
Estimated Afr/Ap 17 Apr  010/012
Predicted Afr/Ap 18 Apr-20 Apr  011/012-009/010-009/010

VI.  Geomagnetic Activity Probabilities 18 Apr-20 Apr
A.  Middle Latitudes
Active                30/25/25
Minor Storm           10/05/05
Major-severe storm    01/01/01
B.  High Latitudes
Active                15/15/15
Minor Storm           25/30/30
Major-severe storm    40/30/30