Joint USAF/NOAA Solar Geophysical Activity Report and Forecast 20 May 2022

Joint USAF/NOAA Solar Geophysical Activity Report and Forecast
SDF Number 140 Issued at 2200Z on 20 May 2022

IA. Analysis of Solar Active Regions and Activity from 19/2100Z to 20/2100Z: Solar activity has been at moderate levels for the past 24 hours. The largest solar event of the period was a M3 event observed at 20/0745Z from Region 3014 (N24W09). 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 days one, two, and three (21 May, 22 May, 23 May).

IIA. Geophysical Activity Summary 19/2100Z to 20/2100Z: The geomagnetic field has been at quiet to unsettled levels for the past 24 hours. Solar wind speed reached a peak of 608 km/s at 20/1541Z. Total IMF reached 7 nT at 20/1845Z. The maximum southward component of Bz reached -6 nT at 20/1540Z. Electrons greater than 2 MeV at geosynchronous orbit reached a peak level of 225 pfu.

IIB. Geophysical Activity Forecast: The geomagnetic field is expected to be at quiet to unsettled levels on days one and two (21 May, 22 May) and quiet levels on day three (23 May). Protons greater than 10 Mev have a slight chance of crossing threshold on days two and three (22 May, 23 May).

III. Event probabilities 21 May-23 May
Class M 40/40/40
Class X 05/05/05
Proton 05/10/10
PCAF green

IV. Penticton 10.7 cm Flux
Observed 20 May 166
Predicted 21 May-23 May 160/162/165
90 Day Mean 20 May 124

V. Geomagnetic A Indices
Observed Afr/Ap 19 May 010/009
Estimated Afr/Ap 20 May 011/012
Predicted Afr/Ap 21 May-23 May 007/010-007/010-005/005

VI. Geomagnetic Activity Probabilities 21 May-23 May
A. Middle Latitudes
Active 25/25/10
Minor Storm 05/05/01
Major-severe storm 01/01/01
B. High Latitudes
Active 15/15/15
Minor Storm 30/30/20
Major-severe storm 30/30/20