Joint USAF/NOAA Solar Geophysical Activity Report and Forecast 20 October 2021

Joint USAF/NOAA Solar Geophysical Activity Report and Forecast
SDF Number 293 Issued at 2200Z on 20 Oct 2021

IA. Analysis of Solar Active Regions and Activity from 19/2100Z to 20/2100Z: Solar activity has been at very low levels for the past 24 hours. There are currently 1 numbered sunspot regions on the disk.

IB. Solar Activity Forecast: Solar activity is expected to be very low on days one, two, and three (21 Oct, 22 Oct, 23 Oct).

IIA. Geophysical Activity Summary 19/2100Z to 20/2100Z: The geomagnetic field has been at quiet to unsettled levels for the past 24 hours. Solar wind speed reached a peak of 447 km/s at 20/2034Z. Total IMF reached 10 nT at 20/2048Z. The maximum southward component of Bz reached -5 nT at 20/1953Z. Electrons greater than 2 MeV at geosynchronous orbit reached a peak level of 155 pfu.

IIB. Geophysical Activity Forecast: The geomagnetic field is expected to be at quiet to unsettled levels on days one and two (21 Oct, 22 Oct) and quiet levels on day three (23 Oct).

III. Event probabilities 21 Oct-23 Oct
Class M 01/01/01
Class X 01/01/01
Proton 01/01/01
PCAF green

IV. Penticton 10.7 cm Flux
Observed 20 Oct 076
Predicted 21 Oct-23 Oct 076/076/080
90 Day Mean 20 Oct 082

V. Geomagnetic A Indices
Observed Afr/Ap 19 Oct 009/010
Estimated Afr/Ap 20 Oct 008/008
Predicted Afr/Ap 21 Oct-23 Oct 009/010-008/008-006/005

VI. Geomagnetic Activity Probabilities 21 Oct-23 Oct
A. Middle Latitudes
Active 25/25/15
Minor Storm 05/05/01
Major-severe storm 01/01/01
B. High Latitudes
Active 20/15/15
Minor Storm 30/30/20
Major-severe storm 30/30/20