Joint USAF/NOAA Solar Geophysical Activity Report and Forecast SDF Number 229 Issued at 2200Z on 17 Aug 2022

IA. Analysis of Solar Active Regions and Activity from 16/2100Z to 17/2100Z: Solar activity has been at moderate levels for the past 24 hours. The largest solar event of the period was a M2 event observed at 17/1345Z from Region 3078 (S20W34). There are currently 5 numbered sunspot regions on the disk.

IB. Solar Activity Forecast: Solar activity is expected to be low with a chance for M-class flares and a slight chance for an X-class flare on days one, two, and three (18 Aug, 19 Aug, 20 Aug).

IIA. Geophysical Activity Summary 16/2100Z to 17/2100Z: The geomagnetic field has been at quiet to major storm levels for the past 24 hours. Solar wind speed reached a peak of 529 km/s at 17/1841Z. Total IMF reached 18 nT at 17/0343Z. The maximum southward component of Bz reached -17 nT at 17/1850Z. Electrons greater than 2 MeV at geosynchronous orbit reached a peak level of 6038 pfu.

IIB. Geophysical Activity Forecast: The geomagnetic field is expected to be at active to severe storm levels on day one (18 Aug), unsettled to major storm levels on day two (19 Aug) and unsettled to active levels on day three (20 Aug). Protons have a slight chance of crossing threshold on days one, two, and three (18 Aug, 19 Aug, 20 Aug).

III. Event probabilities 18 Aug-20 Aug
Class M 40/40/40
Class X 10/10/10
Proton 10/10/10
PCAF green

IV. Penticton 10.7 cm Flux
Observed 17 Aug 123
Predicted 18 Aug-20 Aug 125/125/120
90 Day Mean 17 Aug 121

V. Geomagnetic A Indices
Observed Afr/Ap 16 Aug 005/004
Estimated Afr/Ap 17 Aug 020/037
Predicted Afr/Ap 18 Aug-20 Aug 039/056-022/030-013/018

VI. Geomagnetic Activity Probabilities 18 Aug-20 Aug
A. Middle Latitudes
Active 15/25/40
Minor Storm 35/35/15
Major-severe storm 50/25/01
B. High Latitudes
Active 01/05/10
Minor Storm 05/15/30
Major-severe storm 90/75/55