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

Joint USAF/NOAA Solar Geophysical Activity Report and Forecast
SDF Number 258 Issued at 2200Z on 15 Sep 2021

IA. Analysis of Solar Active Regions and Activity from 14/2100Z to 15/2100Z: 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 (16 Sep, 17 Sep, 18 Sep).

IIA. Geophysical Activity Summary 14/2100Z to 15/2100Z: The geomagnetic field has been at quiet levels for the past 24 hours. Solar wind speed reached a peak of 465 km/s at 14/2355Z. Electrons greater than 2 MeV at geosynchronous orbit reached a peak level of 456 pfu.

IIB. Geophysical Activity Forecast: The geomagnetic field is expected to be at quiet levels on day one (16 Sep) and quiet to active levels on days two and three (17 Sep, 18 Sep).

III. Event probabilities 16 Sep-18 Sep
Class M 01/01/01
Class X 01/01/01
Proton 01/01/01
PCAF green

IV. Penticton 10.7 cm Flux
Observed 15 Sep 075
Predicted 16 Sep-18 Sep 075/075/075
90 Day Mean 15 Sep 082

V. Geomagnetic A Indices
Observed Afr/Ap 14 Sep 005/006
Estimated Afr/Ap 15 Sep 005/005
Predicted Afr/Ap 16 Sep-18 Sep 006/005-012/015-013/015

VI. Geomagnetic Activity Probabilities 16 Sep-18 Sep
A. Middle Latitudes
Active 10/40/45
Minor Storm 01/20/20
Major-severe storm 01/01/01
B. High Latitudes
Active 15/10/10
Minor Storm 20/35/25
Major-severe storm 20/50/65