- Nov 13, 2023
Joint USAF/NOAA Solar Geophysical Activity Report and Forecast SDF Number 291 Issued at 2200Z on 18 Oct 2023
IA. Analysis of Solar Active Regions and Activity from 17/2100Z to 18/2100Z: Solar activity has been at very low levels for the past 24 hours. There are currently 3 numbered sunspot regions on the disk.
IB. Solar Activity Forecast: Solar activity is likely to be low on days one, two, and three (19 Oct, 20 Oct, 21 Oct).
IIA. Geophysical Activity Summary 17/2100Z to 18/2100Z: The geomagnetic field has been at quiet to unsettled levels for the past 24 hours. Solar wind speed reached a peak of 473 km/s at 18/1641Z. Total IMF reached 34 nT at 18/1813Z. The maximum southward component of Bz reached -10 nT at 18/1314Z. Electrons greater than 2 MeV at geosynchronous orbit reached a peak level of 154 pfu.
IIB. Geophysical Activity Forecast: The geomagnetic field is expected to be at quiet to minor storm levels on day one (19 Oct), unsettled to minor storm levels on day two (20 Oct) and unsettled to active levels on day three (21 Oct).
III. Event probabilities 19 Oct-21 Oct
Class M 05/05/05
Class X 01/01/01
IV. Penticton 10.7 cm Flux
Observed 18 Oct 135
Predicted 19 Oct-21 Oct 135/135/140
90 Day Mean 18 Oct 156
V. Geomagnetic A Indices
Observed Afr/Ap 17 Oct 002/002
Estimated Afr/Ap 18 Oct 007/008
Predicted Afr/Ap 19 Oct-21 Oct 015/020-015/022-018/014
VI. Geomagnetic Activity Probabilities 19 Oct-21 Oct
A. Middle Latitudes
Minor Storm 25/25/10
Major-severe storm 05/05/01
B. High Latitudes
Minor Storm 25/30/30
Major-severe storm 60/55/40