Joint USAF/NOAA Solar Geophysical Activity Report and Forecast 27 March 2021

Joint USAF/NOAA Solar Geophysical Activity Report and Forecast
SDF Number 86 Issued at 2200Z on 27 Mar 2021

IA. Analysis of Solar Active Regions and Activity from 26/2100Z to 27/2100Z: 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 with a slight chance for a C-class flare on days one, two, and three (28 Mar, 29 Mar, 30 Mar).

IIA. Geophysical Activity Summary 26/2100Z to 27/2100Z: The geomagnetic field has been at quiet to unsettled levels for the past 24 hours. Solar wind speed reached a peak of 414 km/s at 27/1849Z. Total IMF reached 7 nT at 27/1903Z. The maximum southward component of Bz reached -4 nT at 27/1903Z. Electrons greater than 2 MeV at geosynchronous orbit reached a peak level of 888 pfu.

IIB. Geophysical Activity Forecast: The geomagnetic field is expected to be at unsettled to minor storm levels on day one (28 Mar), unsettled to active levels on day two (29 Mar) and quiet to active levels on day three (30 Mar).

III. Event probabilities 28 Mar-30 Mar
Class M 01/01/01
Class X 01/01/01
Proton 01/01/01
PCAF green

IV. Penticton 10.7 cm Flux
Observed 27 Mar 080
Predicted 28 Mar-30 Mar 078/077/077
90 Day Mean 27 Mar 076

V. Geomagnetic A Indices
Observed Afr/Ap 26 Mar 011/010
Estimated Afr/Ap 27 Mar 006/010
Predicted Afr/Ap 28 Mar-30 Mar 020/025-015/018-014/015

VI. Geomagnetic Activity Probabilities 28 Mar-30 Mar
A. Middle Latitudes
Active 40/40/40
Minor Storm 30/30/20
Major-severe storm 05/05/05
B. High Latitudes
Active 05/10/10
Minor Storm 25/25/30
Major-severe storm 60/60/50