Joint USAF/NOAA Solar Geophysical Activity Report and Forecast 4 April 2021

Joint USAF/NOAA Solar Geophysical Activity Report and Forecast
SDF Number 93 Issued at 2200Z on 03 Apr 2021

IA. Analysis of Solar Active Regions and Activity from 02/2100Z to 03/2100Z: Solar activity has been at very low levels for the past 24 hours. There are currently 0 numbered sunspot regions on the disk.

IB. Solar Activity Forecast: Solar activity is expected to be very low on days one, two, and three (04 Apr, 05 Apr, 06 Apr).

IIA. Geophysical Activity Summary 02/2100Z to 03/2100Z: The geomagnetic field has been at quiet levels for the past 24 hours. Solar wind speed reached a peak of 409 km/s at 03/0000Z. Total IMF reached 8 nT at 02/2101Z. The maximum southward component of Bz reached -3 nT at 03/1105Z. Electrons greater than 2 MeV at geosynchronous orbit reached a peak level of 158 pfu.

IIB. Geophysical Activity Forecast: The geomagnetic field is expected to be at quiet levels on day one (04 Apr) and quiet to unsettled levels on days two and three (05 Apr, 06 Apr).

III. Event probabilities 04 Apr-06 Apr
Class M 01/01/01
Class X 01/01/01
Proton 01/01/01
PCAF green

IV. Penticton 10.7 cm Flux
Observed 03 Apr 073
Predicted 04 Apr-06 Apr 073/073/072
90 Day Mean 03 Apr 076

V. Geomagnetic A Indices
Observed Afr/Ap 02 Apr 004/005
Estimated Afr/Ap 03 Apr 005/005
Predicted Afr/Ap 04 Apr-06 Apr 006/005-006/008-008/008

VI. Geomagnetic Activity Probabilities 04 Apr-06 Apr
A. Middle Latitudes
Active 15/20/25
Minor Storm 05/05/05
Major-severe storm 01/01/01
B. High Latitudes
Active 20/20/20
Minor Storm 25/30/30
Major-severe storm 20/25/25