Joint USAF/NOAA Solar Geophysical Activity Report and Forecast 10 May 2021

Joint USAF/NOAA Solar Geophysical Activity Report and Forecast
SDF Number 130 Issued at 2200Z on 10 May 2021

IA. Analysis of Solar Active Regions and Activity from 09/2100Z to 10/2100Z: 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 likely to be low with a slight chance for an M-class flare on days one, two, and three (11 May, 12 May, 13 May).

IIA. Geophysical Activity Summary 09/2100Z to 10/2100Z: The geomagnetic field has been at quiet levels for the past 24 hours. Solar wind speed reached a peak of 367 km/s at 10/0422Z. Total IMF reached 12 nT at 10/0514Z. The maximum southward component of Bz reached -5 nT at 10/0741Z. Electrons greater than 2 MeV at geosynchronous orbit reached a peak level of 619 pfu.

IIB. Geophysical Activity Forecast: The geomagnetic field is expected to be at quiet to unsettled levels on day one (11 May) and quiet to active levels on days two and three (12 May, 13 May).

III. Event probabilities 11 May-13 May
Class M 15/15/15
Class X 01/01/01
Proton 01/01/01
PCAF green

IV. Penticton 10.7 cm Flux
Observed 10 May 077
Predicted 11 May-13 May 077/077/080
90 Day Mean 10 May 076

V. Geomagnetic A Indices
Observed Afr/Ap 09 May 006/002
Estimated Afr/Ap 10 May 007/007
Predicted Afr/Ap 11 May-13 May 008/008-007/008-014/016

VI. Geomagnetic Activity Probabilities 11 May-13 May
A. Middle Latitudes
Active 10/30/35
Minor Storm 01/10/10
Major-severe storm 01/01/01
B. High Latitudes
Active 20/15/15
Minor Storm 20/30/30
Major-severe storm 10/40/45