Joint USAF/NOAA Solar Geophysical Activity Report and Forecast 9 May 2021

Joint USAF/NOAA Solar Geophysical Activity Report and Forecast
SDF Number 129 Issued at 2200Z on 09 May 2021

IA. Analysis of Solar Active Regions and Activity from 08/2100Z to 09/2100Z: Solar activity has been at low levels for the past 24 hours. The largest solar event of the period was a C4 event observed at 09/1358Z from Region 2822 (N18E45). There are currently 1 numbered sunspot regions on the disk.

IB. Solar Activity Forecast: Solar activity is likely to be low with a slight chance for an M-class flare on days one, two, and three (10 May, 11 May, 12 May).

IIA. Geophysical Activity Summary 08/2100Z to 09/2100Z: The geomagnetic field has been at quiet levels for the past 24 hours. Solar wind speed reached a peak of 346 km/s at 09/1811Z. Total IMF reached 7 nT at 09/1952Z. The maximum southward component of Bz reached -4 nT at 09/1300Z. Electrons greater than 2 MeV at geosynchronous orbit reached a peak level of 389 pfu.

IIB. Geophysical Activity Forecast: The geomagnetic field is expected to be at quiet to unsettled levels on days one and three (10 May, 12 May) and quiet levels on day two (11 May).

III. Event probabilities 10 May-12 May
Class M 15/15/15
Class X 01/01/01
Proton 01/01/01
PCAF green

IV. Penticton 10.7 cm Flux
Observed 09 May 076
Predicted 10 May-12 May 077/077/079
90 Day Mean 09 May 076

V. Geomagnetic A Indices
Observed Afr/Ap 08 May 004/002
Estimated Afr/Ap 09 May 007/007
Predicted Afr/Ap 10 May-12 May 008/008-006/005-008/008

VI. Geomagnetic Activity Probabilities 10 May-12 May
A. Middle Latitudes
Active 10/10/10
Minor Storm 01/01/01
Major-severe storm 01/01/01
B. High Latitudes
Active 15/20/15
Minor Storm 25/20/25
Major-severe storm 20/10/20