Joint USAF/NOAA Solar Geophysical Activity Report and Forecast 19 December 2020

Joint USAF/NOAA Solar Geophysical Activity Report and Forecast
SDF Number 354 Issued at 2200Z on 19 Dec 2020

IA. Analysis of Solar Active Regions and Activity from 18/2100Z to 19/2100Z: 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 (20 Dec, 21 Dec, 22 Dec).

IIA. Geophysical Activity Summary 18/2100Z to 19/2100Z: The geomagnetic field has been at quiet levels for the past 24 hours. Solar wind speed reached a peak of 373 km/s at 19/1940Z. Total IMF reached 10 nT at 19/0944Z. The maximum southward component of Bz reached -8 nT at 19/1126Z. Electrons greater than 2 MeV at geosynchronous orbit reached a peak level of 144 pfu.

IIB. Geophysical Activity Forecast: The geomagnetic field is expected to be at quiet levels on day one (20 Dec), quiet to active levels on day two (21 Dec) and quiet to unsettled levels on day three (22 Dec).

III. Event probabilities 20 Dec-22 Dec
Class M 01/01/01
Class X 01/01/01
Proton 01/01/01
PCAF green

IV. Penticton 10.7 cm Flux
Observed 19 Dec 082
Predicted 20 Dec-22 Dec 082/082/082
90 Day Mean 19 Dec 082

V. Geomagnetic A Indices
Observed Afr/Ap 18 Dec 002/001
Estimated Afr/Ap 19 Dec 004/005
Predicted Afr/Ap 20 Dec-22 Dec 006/005-010/012-007/008

VI. Geomagnetic Activity Probabilities 20 Dec-22 Dec
A. Middle Latitudes
Active 10/30/20
Minor Storm 01/10/05
Major-severe storm 01/01/01
B. High Latitudes
Active 20/15/15
Minor Storm 20/30/25
Major-severe storm 10/40/25