Joint USAF/NOAA Solar Geophysical Activity Report and Forecast 1 September 2021

Joint USAF/NOAA Solar Geophysical Activity Report and Forecast
SDF Number 244 Issued at 2200Z on 01 Sep 2021

IA. Analysis of Solar Active Regions and Activity from 31/2100Z to01/2100Z: 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 01/0854Z from Region 2860 (S27W64). There are currently 2 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 on days one and two (02 Sep, 03 Sep) and expected to be very low with a slight chance for a C-class flare on day three (04 Sep).

IIA. Geophysical Activity Summary 31/2100Z to 01/2100Z: The geomagnetic field has been at quiet levels for the past 24 hours. Solar wind speed reached a peak of 345 km/s at 01/1226Z. Total IMF reached 5 nT at 01/0450Z. The maximum southward component of Bz reached -4 nT at 01/0921Z. Electrons greater than 2 MeV at geosynchronous orbit reached a peak level of 3639 pfu.

IIB. Geophysical Activity Forecast: The geomagnetic field is expected to be at unsettled to major storm levels on day one (02 Sep), quiet to active levels on day two (03 Sep) and quiet levels on day three (04 Sep).

III. Event probabilities 02 Sep-04 Sep
Class M 05/05/01
Class X 01/01/01
Proton 01/01/01
PCAF green

IV. Penticton 10.7 cm Flux
Observed 01 Sep 084
Predicted 02 Sep-04 Sep 084/082/080
90 Day Mean 01 Sep 080

V. Geomagnetic A Indices
Observed Afr/Ap 31 Aug 009/008
Estimated Afr/Ap 01 Sep 010/012
Predicted Afr/Ap 02 Sep-04 Sep 023/030-010/012-006/005

VI. Geomagnetic Activity Probabilities 02 Sep-04 Sep
A. Middle Latitudes
Active 35/30/15
Minor Storm 30/10/05
Major-severe storm 10/01/01
B. High Latitudes
Active 10/15/15
Minor Storm 25/30/25
Major-severe storm 65/40/20