Joint USAF/NOAA Solar Geophysical Activity Report and Forecast 26 May 2022

Joint USAF/NOAA Solar Geophysical Activity Report and Forecast
SDF Number 146 Issued at 2200Z on 26 May 2022

IA. Analysis of Solar Active Regions and Activity from 25/2100Z to Region 3017 (N12W71). There are currently 7 numbered sunspot regions on the disk.

IB. Solar Activity Forecast: Solar activity is expected to be low with a chance for M-class flares on day one (27 May) and expected to be low with a slight chance for an M-class flare on day two (28 May) and expected to be very low with a chance for a C-class flares on day three (29 May).

IIA. Geophysical Activity Summary 25/2100Z to 26/2100Z: The geomagnetic field has been at quiet levels for the past 24 hours. Solar wind speed reached a peak of 388 km/s at 26/0129Z. Total IMF reached 7 nT at 26/1921Z. The maximum southward component of Bz reached -3 nT at 26/1013Z. Electrons greater than 2 MeV at geosynchronous orbit reached a peak level of 775 pfu.

IIB. Geophysical Activity Forecast: The geomagnetic field is expected to be at quiet to active levels on days one, two, and three (27 May, 28 May, 29 May). Protons greater than 10 Mev have a slight chance of crossing threshold on day one (27 May).

III. Event probabilities 27 May-29 May
Class M 30/20/05
Class X 05/05/01
Proton 10/05/01
PCAF green

IV. Penticton 10.7 cm Flux
Observed 26 May 123
Predicted 27 May-29 May 120/115/110
90 Day Mean 26 May 128

V. Geomagnetic A Indices
Observed Afr/Ap 25 May 007/006
Estimated Afr/Ap 26 May 007/010
Predicted Afr/Ap 27 May-29 May 012/015-015/018-012/015

VI. Geomagnetic Activity Probabilities 27 May-29 May
A. Middle Latitudes
Active 30/35/25
Minor Storm 10/20/05
Major-severe storm 01/05/01
B. High Latitudes
Active 15/10/20
Minor Storm 30/30/30
Major-severe storm 40/50/30