Joint USAF/NOAA Solar Geophysical Activity Report and Forecast 30 December 2021

Joint USAF/NOAA Solar Geophysical Activity Report and Forecast
SDF Number 364 Issued at 2200Z on 30 Dec 2021

IA. Analysis of Solar Active Regions and Activity from 29/2100Z to 30/2100Z: Solar activity has been at very low levels for the past 24 hours. There are currently 5 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 (31 Dec, 01 Jan, 02 Jan).

IIA. Geophysical Activity Summary 29/2100Z to 30/2100Z: The geomagnetic field has been at quiet to unsettled levels for the past 24 hours. Solar wind speed reached a peak of 517 km/s at 30/1237Z. Total IMF reached 21 nT at 30/0035Z. The maximum southward component of Bz reached -10 nT at 30/0109Z. Electrons greater than 2 MeV at geosynchronous orbit reached a peak level of 324 pfu.

IIB. Geophysical Activity Forecast: The geomagnetic field is expected to be at quiet to unsettled levels on days one and two (31 Dec, 01 Jan) and quiet to active levels on day three (02 Jan).

III. Event probabilities 31 Dec-02 Jan
Class M 10/10/10
Class X 05/05/05
Proton 05/05/05
PCAF green

IV. Penticton 10.7 cm Flux
Observed 30 Dec 102
Predicted 31 Dec-02 Jan 102/100/100
90 Day Mean 30 Dec 093

V. Geomagnetic A Indices
Observed Afr/Ap 29 Dec 005/005
Estimated Afr/Ap 30 Dec 009/009
Predicted Afr/Ap 31 Dec-02 Jan 007/008-005/006-011/012

VI. Geomagnetic Activity Probabilities 31 Dec-02 Jan
A. Middle Latitudes
Active 20/20/30
Minor Storm 05/05/10
Major-severe storm 01/01/01
B. High Latitudes
Active 20/15/15
Minor Storm 30/25/30
Major-severe storm 25/25/40