- Press Release
- Mar 21, 2023
Joint USAF/NOAA Solar Geophysical Activity Report and Forecast SDF Number 74 Issued at 2200Z on 15 Mar 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 C1 event observed at 14/2226Z from Region 3254 (S24W28). There are currently 8 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 on day one (16 Mar) and expected to be very low with a chance for a C-class flares and a slight chance for an M-class flare on days two and three (17 Mar, 18 Mar).
IIA. Geophysical Activity Summary 14/2100Z to 15/2100Z: The geomagnetic field has been at quiet to major storm levels for the past 24 hours. Solar wind speed reached a peak of 584 km/s at 15/0435Z. Total IMF reached 26 nT at 15/0502Z. The maximum southward component of Bz reached -17 nT at 15/0435Z. Protons greater than 10 MeV at geosynchronous orbit reached a peak level of 21 pfu at 15/0425Z. Electrons greater than 2 MeV at geosynchronous orbit reached a peak level of 157 pfu.
IIB. Geophysical Activity Forecast: The geomagnetic field is expected to be at quiet to minor storm levels on day one (16 Mar), quiet to unsettled levels on day two (17 Mar) and quiet levels on day three (18 Mar). Protons greater than 10 Mev have a chance of crossing threshold on day one (16 Mar).
III. Event probabilities 16 Mar-18 Mar
Class M 05/10/10
Class X 01/01/01
IV. Penticton 10.7 cm Flux
Observed 15 Mar 136
Predicted 16 Mar-18 Mar 138/145/142
90 Day Mean 15 Mar 171
V. Geomagnetic A Indices
Observed Afr/Ap 14 Mar 012/014
Estimated Afr/Ap 15 Mar 019/025
Predicted Afr/Ap 16 Mar-18 Mar 021/025-007/010-006/005
VI. Geomagnetic Activity Probabilities 16 Mar-18 Mar
A. Middle Latitudes
Minor Storm 30/05/01
Major-severe storm 15/01/01
B. High Latitudes
Minor Storm 20/25/20
Major-severe storm 70/25/20