Joint USAF/NOAA Solar Geophysical Activity Report and Forecast 24 August 2021

Joint USAF/NOAA Solar Geophysical Activity Report and Forecast
SDF Number 236 Issued at 2200Z on 24 Aug 2021

IA. Analysis of Solar Active Regions and Activity from 23/2100Z to 24/2100Z: Solar activity has been at low levels for the past 24 hours. The largest solar event of the period was a C1 event observed at 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 (25 Aug, 26 Aug, 27 Aug).

IIA. Geophysical Activity Summary 23/2100Z to 24/2100Z: The geomagnetic field has been at quiet levels for the past 24 hours. Solar wind speed reached a peak of 345 km/s at 24/2035Z. Total IMF reached 7 nT at 24/2026Z. The maximum southward component of Bz reached -4 nT at 24/0831Z. Electrons greater than 2 MeV at geosynchronous orbit reached a peak level of 143 pfu.

IIB. Geophysical Activity Forecast: The geomagnetic field is expected to be at quiet to active levels on days one and three (25 Aug, 27 Aug) and unsettled to active levels on day two (26 Aug).

III. Event probabilities 25 Aug-27 Aug
Class M 01/01/01
Class X 01/01/01
Proton 01/01/01
PCAF green

IV. Penticton 10.7 cm Flux
Observed 24 Aug 081
Predicted 25 Aug-27 Aug 080/080/080
90 Day Mean 24 Aug 079

V. Geomagnetic A Indices
Observed Afr/Ap 23 Aug 008/002
Estimated Afr/Ap 24 Aug 005/006
Predicted Afr/Ap 25 Aug-27 Aug 012/015-014/018-010/012

VI. Geomagnetic Activity Probabilities 25 Aug-27 Aug
A. Middle Latitudes
Active 30/40/30
Minor Storm 10/20/10
Major-severe storm 01/05/01
B. High Latitudes
Active 15/10/15
Minor Storm 25/30/25
Major-severe storm 40/55/40