Joint USAF/NOAA Solar Geophysical Activity Report and Forecast 16 August 2021

Joint USAF/NOAA Solar Geophysical Activity Report and Forecast
SDF Number 228 Issued at 2200Z on 16 Aug 2021

IA. Analysis of Solar Active Regions and Activity from 15/2100Z to 16/2100Z: 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 (17 Aug, 18 Aug, 19 Aug).

IIA. Geophysical Activity Summary 15/2100Z to 16/2100Z: The geomagnetic field has been at quiet to unsettled levels for the past 24 hours. Solar wind speed reached a peak of 518 km/s at 15/2317Z. Total IMF reached 5 nT at 16/0336Z. The maximum southward component of Bz reached -5 nT at 15/2116Z. Electrons greater than 2 MeV at geosynchronous orbit reached a peak level of 438 pfu.

IIB. Geophysical Activity Forecast: The geomagnetic field is expected to be at quiet to unsettled levels on day one (17 Aug) and quiet levels on days two and three (18 Aug, 19 Aug).

III. Event probabilities 17 Aug-19 Aug
Class M 01/01/01
Class X 01/01/01
Proton 01/01/01
PCAF green

IV. Penticton 10.7 cm Flux
Observed 16 Aug 074
Predicted 17 Aug-19 Aug 074/074/073
90 Day Mean 16 Aug 079

V. Geomagnetic A Indices
Observed Afr/Ap 15 Aug 013/010
Estimated Afr/Ap 16 Aug 008/008
Predicted Afr/Ap 17 Aug-19 Aug 006/008-005/005-005/005

VI. Geomagnetic Activity Probabilities 17 Aug-19 Aug
A. Middle Latitudes
Active 15/10/10
Minor Storm 01/01/01
Major-severe storm 01/01/01
B. High Latitudes
Active 15/15/15
Minor Storm 25/20/20
Major-severe storm 20/15/15