Joint USAF/NOAA Solar Geophysical Activity Report and Forecast 29 May 2021

Joint USAF/NOAA Solar Geophysical Activity Report and Forecast
SDF Number 149 Issued at 2200Z on 29 May 2021

IA. Analysis of Solar Active Regions and Activity from 28/2100Z to 29/2100Z: Solar activity has been at low levels for the past 24 hours. The largest solar event of the period was a C9 event observed at 28/2313Z from Region 2824 (N19W68). There are currently 2 numbered sunspot regions on the disk.

IB. Solar Activity Forecast: Solar activity is expected to be very low with a chance for a C-class flares and a slight chance for an M-class flare on day one (30 May) and expected to be very low with a slight chance for a C-class flare on day two (31 May) and expected to be very low on day three (01 Jun).

IIA. Geophysical Activity Summary 28/2100Z to 29/2100Z: The geomagnetic field has been at quiet levels for the past 24 hours. Solar wind speed reached a peak of 476 km/s at 29/1904Z. Total IMF reached 8 nT at 29/0409Z. The maximum southward component of Bz reached -6 nT at 29/1001Z. Protons greater than 10 MeV at geosynchronous orbit reached a peak level of 15 pfu at 29/0320Z. Electrons greater than 2 MeV at geosynchronous orbit reached a peak level of 134 pfu.

IIB. Geophysical Activity Forecast: The geomagnetic field is expected to be at quiet to unsettled levels on day one (30 May), quiet levels on day two (31 May) and quiet to active levels on day three (01 Jun).

III. Event probabilities 30 May-01 Jun
Class M 15/01/01
Class X 01/01/01
Proton 05/01/01
PCAF green

IV. Penticton 10.7 cm Flux
Observed 29 May 076
Predicted 30 May-01 Jun 074/072/072
90 Day Mean 29 May 076

V. Geomagnetic A Indices
Observed Afr/Ap 28 May 003/003
Estimated Afr/Ap 29 May 004/005
Predicted Afr/Ap 30 May-01 Jun 008/008-006/005-015/018

VI. Geomagnetic Activity Probabilities 30 May-01 Jun
A. Middle Latitudes
Active 15/10/30
Minor Storm 05/01/10
Major-severe storm 01/01/01
B. High Latitudes
Active 15/15/15
Minor Storm 25/20/35
Major-severe storm 25/10/40