- Press Release
- Apr 1, 2023
Joint USAF/NOAA Solar Geophysical Activity Report and Forecast SDF Number 58 Issued at 2200Z on 27 Feb 2023
IA. Analysis of Solar Active Regions and Activity from 26/2100Z to 27/2100Z: Solar activity has been at low levels for the past 24 hours. The largest solar event of the period was a C4 event observed at 27/1022Z from Region 3234 (N25W22). 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 (28 Feb, 01 Mar, 02 Mar).
IIA. Geophysical Activity Summary 26/2100Z to 27/2100Z: The geomagnetic field has been at minor storm to severe storm levels for the past 24 hours. Solar wind speed reached a peak of 883 km/s at 27/1250Z. Total IMF reached 20 nT at 27/1025Z. The maximum southward component of Bz reached -19 nT at 27/1030Z. Protons greater than 10 MeV at geosynchronous orbit reached a peak level of 15 pfu at 26/2115Z. Electrons greater than 2 MeV at geosynchronous orbit reached a peak level of 266 pfu.
IIB. Geophysical Activity Forecast: The geomagnetic field is expected to be at unsettled to major storm levels on day one (28 Feb), unsettled to active levels on day two (01 Mar) and quiet to unsettled levels on day three (02 Mar). Protons have a slight chance of crossing threshold on days one, two, and three (28 Feb, 01 Mar, 02 Mar).
III. Event probabilities 28 Feb-02 Mar
Class M 50/45/45
Class X 15/10/10
IV. Penticton 10.7 cm Flux
Observed 27 Feb 161
Predicted 28 Feb-02 Mar 160/158/154
90 Day Mean 27 Feb 167
V. Geomagnetic A Indices
Observed Afr/Ap 26 Feb 018/022
Estimated Afr/Ap 27 Feb 060/102
Predicted Afr/Ap 28 Feb-02 Mar 023/036-014/016-007/010
VI. Geomagnetic Activity Probabilities 28 Feb-02 Mar
A. Middle Latitudes
Minor Storm 35/20/05
Major-severe storm 25/05/01
B. High Latitudes
Minor Storm 20/25/30
Major-severe storm 70/55/30