Joint USAF/NOAA Solar Geophysical Activity Report and Forecast 28 May 2022

Joint USAF/NOAA Solar Geophysical Activity Report and Forecast
SDF Number 148 Issued at 2200Z on 28 May 2022

IA. Analysis of Solar Active Regions and Activity from 27/2100Z to 28/2100Z: Solar activity has been at low levels for the past 24 hours. The largest solar event of the period was a C1 event observed at 28/1904Z from Region 3021 (N13W10). There are currently 3 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 on days one, two, and three (29 May, 30 May, 31 May).

IIA. Geophysical Activity Summary 27/2100Z to 28/2100Z: The geomagnetic field has been at quiet to minor storm levels for the past 24 hours. Solar wind speed reached a peak of 571 km/s at 28/0442Z. Total IMF reached 11 nT at 27/2317Z. The maximum southward component of Bz reached -9 nT at 27/2143Z. Electrons greater than 2 MeV at geosynchronous orbit reached a peak level of 150 pfu.

IIB. Geophysical Activity Forecast: The geomagnetic field is expected to be at quiet to active levels on day one (29 May), unsettled levels on day two (30 May) and quiet to unsettled levels on day three (31 May).

III. Event probabilities 29 May-31 May
Class M 01/01/01
Class X 01/01/01
Proton 01/01/01
PCAF green

IV. Penticton 10.7 cm Flux
Observed 28 May 102
Predicted 29 May-31 May 100/100/100
90 Day Mean 28 May 128

V. Geomagnetic A Indices
Observed Afr/Ap 27 May 014/015
Estimated Afr/Ap 28 May 021/025
Predicted Afr/Ap 29 May-31 May 012/015-011/012-007/010

VI. Geomagnetic Activity Probabilities 29 May-31 May
A. Middle Latitudes
Active 25/10/20
Minor Storm 05/01/05
Major-severe storm 01/01/01
B. High Latitudes
Active 20/20/15
Minor Storm 30/20/20
Major-severe storm 30/10/25