Joint USAF/NOAA Solar Geophysical Activity Report and Forecast 30 May 2021

Joint USAF/NOAA Solar Geophysical Activity Report and Forecast
SDF Number 150 Issued at 2200Z on 30 May 2021

IA. Analysis of Solar Active Regions and Activity from 29/2100Z to 30/2100Z: 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 expected to be very low with a slight chance for a C-class flare on days one, two, and three (31 May, 01 Jun, 02 Jun).

IIA. Geophysical Activity Summary 29/2100Z to 30/2100Z: The geomagnetic field has been at quiet levels for the past 24 hours. Solar wind speed reached a peak of 491 km/s at 30/0838Z. Total IMF reached 6 nT at 29/2149Z. The maximum southward component of Bz reached -3 nT at 30/2005Z. Electrons greater than 2 MeV at geosynchronous orbit reached a peak level of 350 pfu.

IIB. Geophysical Activity Forecast: The geomagnetic field is expected to be at quiet levels on day one (31 May) and quiet to active levels on days two and three (01 Jun, 02 Jun).

III. Event probabilities 31 May-02 Jun
Class M 01/01/01
Class X 01/01/01
Proton 01/01/01
PCAF green

IV. Penticton 10.7 cm Flux
Observed 30 May 074
Predicted 31 May-02 Jun 072/072/072
90 Day Mean 30 May 077

V. Geomagnetic A Indices
Observed Afr/Ap 29 May 007/005
Estimated Afr/Ap 30 May 007/007
Predicted Afr/Ap 31 May-02 Jun 006/005-015/018-014/015

VI. Geomagnetic Activity Probabilities 31 May-02 Jun
A. Middle Latitudes
Active 10/35/35
Minor Storm 01/10/10
Major-severe storm 01/01/01
B. High Latitudes
Active 15/15/15
Minor Storm 20/30/30
Major-severe storm 10/45/45