Joint USAF/NOAA Solar Geophysical Activity Report and Forecast 26 March 2021

Joint USAF/NOAA Solar Geophysical Activity Report and Forecast
SDF Number 85 Issued at 2200Z on 26 Mar 2021

IA. Analysis of Solar Active Regions and Activity from 25/2100Z to 26/2100Z: 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 slight chance for a C-class flare on days one, two, and three (27Mar, 28 Mar, 29 Mar).

IIA. Geophysical Activity Summary 25/2100Z to 26/2100Z: The geomagnetic field has been at quiet to active levels for the past 24 hours. Solar wind speed reached a peak of 490 km/s at 26/0357Z. Total IMF reached 6 nT at 25/2114Z. The maximum southward component of Bz reached -6 nT at 25/2125Z. Electrons greater than 2 MeV at geosynchronous orbit reached a peak level of 1507 pfu.

IIB. Geophysical Activity Forecast: The geomagnetic field is expected to be at quiet to active levels on days one and three (27 Mar, 29 Mar) and unsettled to minor storm levels on day two (28 Mar).

III. Event probabilities 27 Mar-29 Mar
Class M 01/01/01
Class X 01/01/01
Proton 01/01/01
PCAF green

IV. Penticton 10.7 cm Flux
Observed 26 Mar 080
Predicted 27 Mar-29 Mar 079/077/076
90 Day Mean 26 Mar 077

V. Geomagnetic A Indices
Observed Afr/Ap 25 Mar 018/016
Estimated Afr/Ap 26 Mar 010/012
Predicted Afr/Ap 27 Mar-29 Mar 008/010-020/025-014/020

VI. Geomagnetic Activity Probabilities 27 Mar-29 Mar
A. Middle Latitudes
Active 30/40/40
Minor Storm 15/30/30
Major-severe storm 01/05/05
B. High Latitudes
Active 15/05/10
Minor Storm 30/25/25
Major-severe storm 45/60/60