Joint USAF/NOAA Solar Geophysical Activity Report and Forecast 17 September 2020

Joint USAF/NOAA Solar Geophysical Activity Report and Forecast
SDF Number 261 Issued at 2200Z on 17 Sep 2020

IA. Analysis of Solar Active Regions and Activity from 16/2100Z to 17/2100Z: 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 (18 Sep, 19 Sep, 20 Sep).

IIA. Geophysical Activity Summary 16/2100Z to 17/2100Z: The geomagnetic field has been at quiet levels for the past 24 hours. Solar wind speed reached a peak of 343 km/s at 17/0150Z. Total IMF reached 5 nT at 17/0134Z. The maximum southward component of Bz reached -4 nT at 17/0529Z. Electrons greater than 2 MeV at geosynchronous orbit reached a peak level of 192 pfu.

IIB. Geophysical Activity Forecast: The geomagnetic field is expected to be at quiet levels on days one, two, and three (18 Sep, 19 Sep, 20 Sep).

III. Event probabilities 18 Sep-20 Sep
Class M 01/01/01
Class X 01/01/01
Proton 01/01/01
PCAF green

IV. Penticton 10.7 cm Flux
Observed 17 Sep 070
Predicted 18 Sep-20 Sep 070/070/070
90 Day Mean 17 Sep 070

V. Geomagnetic A Indices
Observed Afr/Ap 16 Sep 003/003
Estimated Afr/Ap 17 Sep 004/004
Predicted Afr/Ap 18 Sep-20 Sep 006/005-006/005-006/005

VI. Geomagnetic Activity Probabilities 18 Sep-20 Sep
A. Middle Latitudes
Active 10/10/05
Minor Storm 01/01/01
Major-severe storm 01/01/01
B. High Latitudes
Active 15/15/15
Minor Storm 15/15/15
Major-severe storm 10/10/05