Joint USAF/NOAA Solar Geophysical Activity Report and Forecast 24 October 2021

Joint USAF/NOAA Solar Geophysical Activity Report and Forecast
SDF Number 297 Issued at 2200Z on 24 Oct 2021

IA. Analysis of Solar Active Regions and Activity from 23/2100Z to 24/2100Z: Solar activity has been at very low levels for the past 24 hours. There are currently 3 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 and a slight chance for an M-class flare on days one, two, and three (25 Oct, 26 Oct, 27 Oct).

IIA. Geophysical Activity Summary 23/2100Z to 24/2100Z: The geomagnetic field has been at quiet levels for the past 24 hours. Solar wind speed reached a peak of 373 km/s at 24/2052Z. Total IMF reached 6 nT at 24/0820Z. The maximum southward component of Bz reached -5 nT at 24/0831Z. Electrons greater than 2 MeV at geosynchronous orbit reached a peak level of 151 pfu.

IIB. Geophysical Activity Forecast: The geomagnetic field is expected to be at quiet levels on days one and two (25 Oct, 26 Oct) and quiet to unsettled levels on day three (27 Oct).

III. Event probabilities 25 Oct-27 Oct
Class M 10/10/10
Class X 01/01/01
Proton 01/01/01
PCAF green

IV. Penticton 10.7 cm Flux
Observed 24 Oct 093
Predicted 25 Oct-27 Oct 094/095/095
90 Day Mean 24 Oct 083

V. Geomagnetic A Indices
Observed Afr/Ap 23 Oct 002/001
Estimated Afr/Ap 24 Oct 004/004
Predicted Afr/Ap 25 Oct-27 Oct 006/005-006/005-008/008

VI. Geomagnetic Activity Probabilities 25 Oct-27 Oct
A. Middle Latitudes
Active 10/15/15
Minor Storm 01/01/05
Major-severe storm 01/01/01
B. High Latitudes
Active 15/15/15
Minor Storm 20/20/25
Major-severe storm 10/20/25