Joint USAF/NOAA Solar Geophysical Activity Report and Forecast 28 March 2021

Joint USAF/NOAA Solar Geophysical Activity Report and Forecast
SDF Number 87 Issued at 2200Z on 28 Mar 2021

IA. Analysis of Solar Active Regions and Activity from 27/2100Z to 28/2100Z: 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 (29 Mar, 30 Mar, 31 Mar).

IIA. Geophysical Activity Summary 27/2100Z to 28/2100Z: The geomagnetic field has been at quiet to active levels for the past 24 hours. Solar wind speed reached a peak of 440 km/s at 28/0611Z. Total IMF reached 8 nT at 27/2217Z. The maximum southward component of Bz reached -7 nT at 28/0021Z. Electrons greater than 2 MeV at geosynchronous orbit reached a peak level of 727 pfu.

IIB. Geophysical Activity Forecast: The geomagnetic field is expected to be at quiet to minor storm levels on day one (29 Mar), quiet to active levels on day two (30 Mar) and quiet to unsettled levels on day three (31 Mar).

III. Event probabilities 29 Mar-31 Mar
Class M 01/01/01
Class X 01/01/01
Proton 01/01/01
PCAF green

IV. Penticton 10.7 cm Flux
Observed 28 Mar 075
Predicted 29 Mar-31 Mar 075/075/075
90 Day Mean 28 Mar 076

V. Geomagnetic A Indices
Observed Afr/Ap 27 Mar 007/007
Estimated Afr/Ap 28 Mar 008/010
Predicted Afr/Ap 29 Mar-31 Mar 013/018-010/012-007/008

VI. Geomagnetic Activity Probabilities 29 Mar-31 Mar
A. Middle Latitudes
Active 40/40/20
Minor Storm 30/20/10
Major-severe storm 05/05/01
B. High Latitudes
Active 10/10/15
Minor Storm 25/30/25
Major-severe storm 60/50/25