Joint USAF/NOAA Solar Geophysical Activity Report and Forecast 18 February 2021

Joint USAF/NOAA Solar Geophysical Activity Report and Forecast
SDF Number 49 Issued at 2200Z on 18 Feb 2021

IA. Analysis of Solar Active Regions and Activity from 17/2100Z to 18/2100Z: Solar activity has been at very low levels for the past 24 hours. 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 (19 Feb, 20 Feb, 21 Feb).

IIA. Geophysical Activity Summary 17/2100Z to 18/2100Z: The geomagnetic field has been at quiet to unsettled levels for the past 24 hours. Solar wind speed reached a peak of 415 km/s at 17/2321Z. Total IMF reached 5 nT at 17/2355Z. The maximum southward component of Bz reached -4 nT at 18/0616Z. Electrons greater than 2 MeV at geosynchronous orbit reached a peak level of 158 pfu.

IIB. Geophysical Activity Forecast: The geomagnetic field is expected to be at quiet levels on day one (19 Feb), quiet to unsettled levels on day two (20 Feb) and unsettled to minor storm levels on day three (21 Feb).

III. Event probabilities 19 Feb-21 Feb
Class M 01/01/01
Class X 01/01/01
Proton 01/01/01
PCAF green

IV. Penticton 10.7 cm Flux
Observed 18 Feb 071
Predicted 19 Feb-21 Feb 071/071/071
90 Day Mean 18 Feb 082

V. Geomagnetic A Indices
Observed Afr/Ap 17 Feb 006/006
Estimated Afr/Ap 18 Feb 005/006
Predicted Afr/Ap 19 Feb-21 Feb 006/005-007/008-015/018

VI. Geomagnetic Activity Probabilities 19 Feb-21 Feb
A. Middle Latitudes
Active 10/15/35
Minor Storm 01/05/15
Major-severe storm 01/01/01
B. High Latitudes
Active 15/15/10
Minor Storm 20/25/25
Major-severe storm 10/25/50