Joint USAF/NOAA Solar Geophysical Activity Report and Forecast 23 February 2021

Joint USAF/NOAA Solar Geophysical Activity Report and Forecast
SDF Number 54 Issued at 2200Z on 23 Feb 2021

IA. Analysis of Solar Active Regions and Activity from 22/2100Z to 23/2100Z: Solar activity has been at very low levels for the past 24 hours. 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, two, and three (24 Feb, 25 Feb, 26 Feb).

IIA. Geophysical Activity Summary 22/2100Z to 23/2100Z: The geomagnetic field has been at quiet to active levels for the past 24 hours. Solar wind speed reached a peak of 636 km/s at 23/0122Z. Total IMF reached 6 nT at 23/0652Z. The maximum southward component of Bz reached -4 nT at 23/0518Z. Electrons greater than 2 MeV at geosynchronous orbit reached a peak level of 14236 pfu.

IIB. Geophysical Activity Forecast: The geomagnetic field is expected to be at quiet to minor storm levels on day one (24 Feb), quiet to unsettled levels on day two (25 Feb) and quiet levels on day three (26 Feb).

III. Event probabilities 24 Feb-26 Feb
Class M 01/01/01
Class X 01/01/01
Proton 01/01/01
PCAF green

IV. Penticton 10.7 cm Flux
Observed 23 Feb 078
Predicted 24 Feb-26 Feb 078/078/078
90 Day Mean 23 Feb 081

V. Geomagnetic A Indices
Observed Afr/Ap 22 Feb 013/013
Estimated Afr/Ap 23 Feb 015/017
Predicted Afr/Ap 24 Feb-26 Feb 020/025-009/010-006/005

VI. Geomagnetic Activity Probabilities 24 Feb-26 Feb
A. Middle Latitudes
Active 45/15/05
Minor Storm 30/01/01
Major-severe storm 05/01/01
B. High Latitudes
Active 05/15/15
Minor Storm 20/25/20
Major-severe storm 70/20/10