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

Joint USAF/NOAA Solar Geophysical Activity Report and Forecast
SDF Number 277 Issued at 2200Z on 04 Oct 2021

IA. Analysis of Solar Active Regions and Activity from 03/2100Z to 04/2100Z: Solar activity has been at very low levels for the past 24 hours. There are currently 2 numbered sunspot regions on the disk.

IB. Solar Activity Forecast: Solar activity is expected to be very low with a chance for a C-class flares on days one, two, and three (05 Oct, 06 Oct, 07 Oct).

IIA. Geophysical Activity Summary 03/2100Z to 04/2100Z: The geomagnetic field has been at quiet to unsettled levels for the past 24 hours. Solar wind speed reached a peak of 408 km/s at 03/2105Z. Total IMF reached 5 nT at 03/2101Z. The maximum southward component of Bz reached -4 nT at 03/2124Z. Electrons greater than 2 MeV at geosynchronous orbit reached a peak level of 271 pfu.

IIB. Geophysical Activity Forecast: The geomagnetic field is expected to be at quiet to unsettled levels on days one and two (05 Oct, 06 Oct) and quiet levels on day three (07 Oct).

III. Event probabilities 05 Oct-07 Oct
Class M 05/05/05
Class X 01/01/01
Proton 01/01/01
PCAF green

IV. Penticton 10.7 cm Flux
Observed 04 Oct 084
Predicted 05 Oct-07 Oct 084/084/084
90 Day Mean 04 Oct 082

V. Geomagnetic A Indices
Observed Afr/Ap 03 Oct 006/006
Estimated Afr/Ap 04 Oct 006/006
Predicted Afr/Ap 05 Oct-07 Oct 007/008-007/008-006/005

VI. Geomagnetic Activity Probabilities 05 Oct-07 Oct
A. Middle Latitudes
Active 20/20/15
Minor Storm 05/05/01
Major-severe storm 01/01/01
B. High Latitudes
Active 20/20/15
Minor Storm 30/30/20
Major-severe storm 25/25/20