- Press Release
- Jun 7, 2023
Joint USAF/NOAA Solar Geophysical Activity Report and Forecast SDF Number 102 Issued at 2200Z on 12 Apr 2023
IA. Analysis of Solar Active Regions and Activity from 11/2100Z to 12/2100Z: Solar activity has been at low levels for the past 24 hours. The largest solar event of the period was a C6 event observed at 12/1153Z from Region 3276 (S21E52). 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 and a slight chance for an X-class flare on days one, two, and three (13 Apr, 14 Apr, 15 Apr).
IIA. Geophysical Activity Summary 11/2100Z to 12/2100Z: The geomagnetic field has been at quiet levels for the past 24 hours. Solar wind speed reached a peak of 468 km/s at 12/1423Z. Total IMF reached 9 nT at 12/1406Z. The maximum southward component of Bz reached -4 nT at 12/1631Z. Electrons greater than 2 MeV at geosynchronous orbit reached a peak level of 146 pfu.
IIB. Geophysical Activity Forecast: The geomagnetic field is expected to be at quiet to unsettled levels on day one (13 Apr), quiet levels on day two (14 Apr) and quiet to active levels on day three (15 Apr).
III. Event probabilities 13 Apr-15 Apr
Class M 45/45/45
Class X 10/10/10
IV. Penticton 10.7 cm Flux
Observed 12 Apr 154
Predicted 13 Apr-15 Apr 155/160/165
90 Day Mean 12 Apr 166
V. Geomagnetic A Indices
Observed Afr/Ap 11 Apr 006/005
Estimated Afr/Ap 12 Apr 005/006
Predicted Afr/Ap 13 Apr-15 Apr 008/005-006/005-011/005
VI. Geomagnetic Activity Probabilities 13 Apr-15 Apr
A. Middle Latitudes
Minor Storm 05/05/15
Major-severe storm 01/01/05
B. High Latitudes
Minor Storm 25/20/30
Major-severe storm 20/15/55