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

Joint USAF/NOAA Solar Geophysical Activity Report and Forecast
SDF Number 77 Issued at 2200Z on 18 Mar 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 is 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 Mar, 20 Mar, 21 Mar).

IIA. Geophysical Activity Summary 17/2100Z to 18/2100Z: The geomagnetic field has been at quiet levels for the past 24 hours. Solar wind speed reached a peak of 350 km/s at 18/0235Z. Total IMF reached 5 nT at 17/2134Z. The maximum southward component of Bz reached -3 nT at 18/0233Z. Electrons greater than 2 MeV at geosynchronous orbit reached a peak level of 1500 pfu.

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

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

IV. Penticton 10.7 cm Flux
Observed 18 Mar 073
Predicted 19 Mar-21 Mar 072/072/072
90 Day Mean 18 Mar 077

V. Geomagnetic A Indices
Observed Afr/Ap 17 Mar 002/004
Estimated Afr/Ap 18 Mar 006/005
Predicted Afr/Ap 19 Mar-21 Mar 008/012-018/024-015/020

VI. Geomagnetic Activity Probabilities 19 Mar-21 Mar
A. Middle Latitudes
Active 35/40/35
Minor Storm 15/25/15
Major-severe storm 01/05/01
B. High Latitudes
Active 20/10/15
Minor Storm 25/25/25
Major-severe storm 35/60/25