Joint USAF/NOAA Solar Geophysical Activity Report and Forecast 9 August 2021

Joint USAF/NOAA Solar Geophysical Activity Report and Forecast
SDF Number 221 Issued at 2200Z on 09 Aug 2021

IA. Analysis of Solar Active Regions and Activity from 08/2100Z to 09/2100Z: 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 09/0004Z from Region 2853 (N23E48). There are currently 1 numbered sunspot regions on the disk.

IB. Solar Activity Forecast: Solar activity is expected to be very low on days one, two, and three (10 Aug, 11 Aug, 12 Aug).

IIA. Geophysical Activity Summary 08/2100Z to 09/2100Z: The geomagnetic field has been at quiet levels for the past 24 hours. Solar wind speed component of Bz reached -5 nT at 09/0727Z. Electrons greater than 2 MeV at geosynchronous orbit reached a peak level of 352 pfu.

IIB. Geophysical Activity Forecast: The geomagnetic field is expected to be at quiet to unsettled levels on day one (10 Aug) and quiet levels on days two and three (11 Aug, 12 Aug).

III. Event probabilities 10 Aug-12 Aug
Class M 01/01/01
Class X 01/01/01
Proton 01/01/01
PCAF green

IV. Penticton 10.7 cm Flux
Observed 09 Aug 073
Predicted 10 Aug-12 Aug 073/073/072
90 Day Mean 09 Aug 079

V. Geomagnetic A Indices
Observed Afr/Ap 08 Aug 006/004
Estimated Afr/Ap 09 Aug 005/006
Predicted Afr/Ap 10 Aug-12 Aug 008/008-006/005-006/005

VI. Geomagnetic Activity Probabilities 10 Aug-12 Aug
A. Middle Latitudes
Active 20/10/10
Minor Storm 05/01/01
Major-severe storm 01/01/01
B. High Latitudes
Active 15/15/15
Minor Storm 25/20/20
Major-severe storm 25/15/15