- Press Release
- Mar 21, 2023
Joint USAF/NOAA Solar Geophysical Activity Report and Forecast SDF Number 50 Issued at 2200Z on 19 Feb 2023
IA. Analysis of Solar Active Regions and Activity from 18/2100Z to 19/2100Z: 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 19/0817Z from Region 3226 (N10W47). 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 (20 Feb, 21 Feb, 22 Feb).
IIA. Geophysical Activity Summary 18/2100Z to 19/2100Z: The geomagnetic field has been at quiet to unsettled levels for the past 24 hours. Solar wind speed reached a peak of 507 km/s at 19/1454Z. Total IMF reached 6 nT at 19/2058Z. The maximum southward component of Bz reached -4 nT at 19/1155Z. Electrons greater than 2 MeV at geosynchronous orbit reached a peak level of 307 pfu.
IIB. Geophysical Activity Forecast: The geomagnetic field is expected to be at unsettled to minor storm levels on day one (20 Feb) and quiet to active levels on days two and three (21 Feb, 22 Feb). Protons have a slight chance of crossing threshold on day one (20 Feb) and have a slight chance of crossing threshold on days two and three (21 Feb, 22 Feb).
III. Event probabilities 20 Feb-22 Feb
Class M 50/50/50
Class X 15/15/15
IV. Penticton 10.7 cm Flux
Observed 19 Feb 169
Predicted 20 Feb-22 Feb 160/150/140
90 Day Mean 19 Feb 163
V. Geomagnetic A Indices
Observed Afr/Ap 18 Feb 005/004
Estimated Afr/Ap 19 Feb 008/012
Predicted Afr/Ap 20 Feb-22 Feb 020/025-014/015-010/012
VI. Geomagnetic Activity Probabilities 20 Feb-22 Feb
A. Middle Latitudes
Minor Storm 30/15/05
Major-severe storm 10/01/01
B. High Latitudes
Minor Storm 20/30/30
Major-severe storm 70/50/35