Joint USAF/NOAA Solar Geophysical Activity Report and Forecast 17 January 2021

Joint USAF/NOAA Solar Geophysical Activity Report and Forecast
SDF Number 17 Issued at 2200Z on 17 Jan 2021

IA. Analysis of Solar Active Regions and Activity from 16/2100Z to 17/2100Z: Solar activity has been at very low levels for the past 24 hours. There are currently 2 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 (18 Jan, 19 Jan, 20 Jan).

IIA. Geophysical Activity Summary 16/2100Z to 17/2100Z: The geomagnetic field has been at quiet levels for the past 24 hours. Solar wind speed reached a peak of 316 km/s at 16/2105Z. Total IMF reached 5 nT at 17/0114Z. The maximum southward component of Bz reached -4 nT at 17/2041Z. Electrons greater than 2 MeV at geosynchronous orbit reached a peak level of 189 pfu.

IIB. Geophysical Activity Forecast: The geomagnetic field is expected to be at quiet to active levels on days one, two, and three (18 Jan, 19 Jan, 20 Jan).

III. Event probabilities 18 Jan-20 Jan
Class M 01/01/01
Class X 01/01/01
Proton 01/01/01
PCAF green

IV. Penticton 10.7 cm Flux
Observed 17 Jan 077
Predicted 18 Jan-20 Jan 077/077/077
90 Day Mean 17 Jan 085

V. Geomagnetic A Indices
Observed Afr/Ap 16 Jan 002/002
Estimated Afr/Ap 17 Jan 003/003
Predicted Afr/Ap 18 Jan-20 Jan 011/012-013/015-011/012

VI. Geomagnetic Activity Probabilities 18 Jan-20 Jan
A. Middle Latitudes
Active 35/40/35
Minor Storm 10/15/10
Major-severe storm 01/01/01
B. High Latitudes
Active 10/10/15
Minor Storm 25/30/30
Major-severe storm 40/55/45