Joint USAF/NOAA Solar Geophysical Activity Report and Forecast 22 December 2020

Joint USAF/NOAA Solar Geophysical Activity Report and Forecast
SDF Number 357 Issued at 2200Z on 22 Dec 2020

IA. Analysis of Solar Active Regions and Activity from 21/2100Z to 22/2100Z: 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 with a slight chance for a C-class flare on days one, two, and three (23 Dec, 24 Dec, 25 Dec).

IIA. Geophysical Activity Summary 21/2100Z to 22/2100Z: The geomagnetic field has been at quiet to active levels for the past 24 hours. Solar wind speed reached a peak of 585 km/s at 22/2028Z. Total IMF reached 19 nT at 21/2322Z. The maximum southward component of Bz reached -11 nT at 21/2102Z. Electrons greater than 2 MeV at geosynchronous orbit reached a peak level of 207 pfu.

IIB. Geophysical Activity Forecast: The geomagnetic field is expected to be at quiet to minor storm levels on days one and two (23 Dec, 24 Dec) and quiet to active levels on day three (25 Dec).

III. Event probabilities 23 Dec-25 Dec
Class M 01/01/01
Class X 01/01/01
Proton 01/01/01
PCAF green

IV. Penticton 10.7 cm Flux
Observed 22 Dec 086
Predicted 23 Dec-25 Dec 086/086/088
90 Day Mean 22 Dec 083

V. Geomagnetic A Indices
Observed Afr/Ap 21 Dec 008/008
Estimated Afr/Ap 22 Dec 012/014
Predicted Afr/Ap 23 Dec-25 Dec 012/018-018/022-011/015

VI. Geomagnetic Activity Probabilities 23 Dec-25 Dec
A. Middle Latitudes
Active 35/40/30
Minor Storm 20/30/15
Major-severe storm 05/10/01
B. High Latitudes
Active 10/05/15
Minor Storm 25/25/30
Major-severe storm 55/65/45