Joint USAF/NOAA Solar Geophysical Activity Report and Forecast 25 April 2022

Joint USAF/NOAA Solar Geophysical Activity Report and Forecast
SDF Number 115 Issued at 2200Z on 25 Apr 2022

IA. Analysis of Solar Active Regions and Activity from 24/2100Z to 25/2100Z: 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 25/0402Z from Region 2993 (N19W45). 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 and a slight chance for an X-class flare on days one, two, and three (26 Apr, 27 Apr, 28 Apr).

IIA. Geophysical Activity Summary 24/2100Z to 25/2100Z: The geomagnetic field has been at quiet levels for the past 24 hours. Solar wind speed reached a peak of 538 km/s at 25/2043Z. Total IMF reached 5 nT at 24/2151Z. The maximum southward component of Bz reached -3 nT at 25/0402Z. Electrons greater than 2 MeV at geosynchronous orbit reached a peak level of 390 pfu.

IIB. Geophysical Activity Forecast: The geomagnetic field is expected to be at quiet levels on days one, two, and three (26 Apr, 27 Apr, 28 Apr). Protons have a slight chance of crossing threshold on days one, two, and three (26 Apr, 27 Apr, 28 Apr).

III. Event probabilities 26 Apr-28 Apr
Class M 40/40/40
Class X 10/10/10
Proton 10/10/10
PCAF green

IV. Penticton 10.7 cm Flux
Observed 25 Apr 157
Predicted 26 Apr-28 Apr 160/160/140
90 Day Mean 25 Apr 118

V. Geomagnetic A Indices
Observed Afr/Ap 24 Apr 005/006
Estimated Afr/Ap 25 Apr 005/005
Predicted Afr/Ap 26 Apr-28 Apr 006/005-005/005-005/005

VI. Geomagnetic Activity Probabilities 26 Apr-28 Apr
A. Middle Latitudes
Active 15/15/15
Minor Storm 01/01/01
Major-severe storm 01/01/01
B. High Latitudes
Active 15/15/15
Minor Storm 20/20/20
Major-severe storm 20/20/20