Joint USAF/NOAA Solar Geophysical Activity Report and Forecast 20 September 2020

Joint USAF/NOAA Solar Geophysical Activity Report and Forecast
SDF Number 264 Issued at 2200Z on 20 Sep 2020

IA. Analysis of Solar Active Regions and Activity from 19/2100Z to 20/2100Z: Solar activity has been at very low levels for the past 24 hours. There are currently 0 numbered sunspot regions on the disk.

IB. Solar Activity Forecast: Solar activity is expected to be very low on days one, two, and three (21 Sep, 22 Sep, 23 Sep).

IIA. Geophysical Activity Summary 19/2100Z to 20/2100Z: The geomagnetic field has been at quiet levels for the past 24 hours. Solar wind speed reached a peak of 304 km/s at 20/1035Z. Total IMF reached 5 nT at 20/2050Z. The maximum southward component of Bz reached -4 nT at20/1331Z. Electrons greater than 2 MeV at geosynchronous orbit reached a peak level of 156 pfu.

IIB. Geophysical Activity Forecast: The geomagnetic field is expected to be at quiet levels on days one and two (21 Sep, 22 Sep) and quiet to unsettled levels on day three (23 Sep).

III. Event probabilities 21 Sep-23 Sep
Class M 01/01/01
Class X 01/01/01
Proton 01/01/01
PCAF green

IV. Penticton 10.7 cm Flux
Observed 20 Sep 070
Predicted 21 Sep-23 Sep 070/070/070
90 Day Mean 20 Sep 070

V. Geomagnetic A Indices
Observed Afr/Ap 19 Sep 004/003
Estimated Afr/Ap 20 Sep 003/004
Predicted Afr/Ap 21 Sep-23 Sep 006/005-006/005-008/010

VI. Geomagnetic Activity Probabilities 21 Sep-23 Sep
A. Middle Latitudes
Active 05/10/20
Minor Storm 01/01/05
Major-severe storm 01/01/01
B. High Latitudes
Active 15/15/15
Minor Storm 15/15/30
Major-severe storm 05/10/25