Joint USAF/NOAA Solar Geophysical Activity Report and Forecast 27 May 2022

Joint USAF/NOAA Solar Geophysical Activity Report and Forecast
SDF Number 147 Issued at 2200Z on 27 May 2022

IA. Analysis of Solar Active Regions and Activity from 26/2100Z to 27/2100Z: Solar activity has been at low levels for the past 24 hours. The largest solar event of the period was a C2 event observed at 27/1127Z from Region 3021 (N13E02). There are currently 6 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 (28 May) and expected to be very low with a chance for a C-class flares on days two and three (29 May, 30 May).

IIA. Geophysical Activity Summary 26/2100Z to 27/2100Z: The geomagnetic field has been at quiet to minor storm levels for the past 24 hours. Solar wind speed reached a peak of 480 km/s at 27/2053Z. Total IMF reached 18 nT at 27/1220Z. The maximum southward component of Bz reached -15 nT at 27/1207Z. Electrons greater than 2 MeV at geosynchronous orbit reached a peak level of 507 pfu.

IIB. Geophysical Activity Forecast: The geomagnetic field is expected to be at quiet to minor storm levels on day one (28 May), quiet to active levels on day two (29 May) and unsettled levels on day three (30 May).

III. Event probabilities 28 May-30 May
Class M 10/01/01
Class X 01/01/01
Proton 01/01/01
PCAF green

IV. Penticton 10.7 cm Flux
Observed 27 May 114
Predicted 28 May-30 May 112/108/110
90 Day Mean 27 May 128

V. Geomagnetic A Indices
Observed Afr/Ap 26 May 006/004
Estimated Afr/Ap 27 May 013/018
Predicted Afr/Ap 28 May-30 May 014/018-012/015-011/012

VI. Geomagnetic Activity Probabilities 28 May-30 May
A. Middle Latitudes
Active 35/25/10
Minor Storm 20/05/01
Major-severe storm 05/01/01
B. High Latitudes
Active 10/20/20
Minor Storm 30/30/20
Major-severe storm 50/30/10