Joint USAF/NOAA Solar Geophysical Activity Report and Forecast SDF Number 135 Issued at 2200Z on 15 May 2023
IA. Analysis of Solar Active Regions and Activity from 14/2100Z to 15/2100Z: Solar activity has been at low levels for the past 24 hours. The largest solar event of the period was a C3 event observed at 15/0051Z from Region 3306 (S18W50). There are currently 6 numbered sunspot regions on the disk.
IB. Solar Activity Forecast: Solar activity is expected to be low with a slight chance for an M-class flare on day one (16 May) and expected to be low with a chance for M-class flares on days two and three (17 May, 18 May).
IIA. Geophysical Activity Summary 14/2100Z to 15/2100Z: The geomagnetic field has been at quiet levels for the past 24 hours. Solar wind speed reached a peak of 535 km/s at 14/2251Z. Total IMF reached 6 nT at 15/0433Z. The maximum southward component of Bz reached -4 nT at 15/1832Z. Electrons greater than 2 MeV at geosynchronous orbit reached a peak level of 191 pfu.
IIB. Geophysical Activity Forecast: The geomagnetic field is expected to be at quiet to active levels on day one (16 May), quiet to unsettled levels on day two (17 May) and quiet levels on day three (18 May).
III. Event probabilities 16 May-18 May
Class M 15/25/25
Class X 01/05/05
Proton 01/01/01
PCAF green
IV. Penticton 10.7 cm Flux
Observed 15 May 135
Predicted 16 May-18 May 135/140/145
90 Day Mean 15 May 156
V. Geomagnetic A Indices
Observed Afr/Ap 14 May 009/008
Estimated Afr/Ap 15 May 003/004
Predicted Afr/Ap 16 May-18 May 009/012-008/008-006/005
VI. Geomagnetic Activity Probabilities 16 May-18 May
A. Middle Latitudes
Active 25/20/10
Minor Storm 05/05/05
Major-severe storm 01/01/01
B. High Latitudes
Active 15/15/15
Minor Storm 20/20/20
Major-severe storm 20/25/15
Space weather
