Joint USAF/NOAA Solar Geophysical Activity Report and Forecast 25 October 2017

Joint USAF/NOAA Solar Geophysical Activity Report and Forecast
SDF Number 298 Issued at 2200Z on 25 Oct 2017

IA.  Analysis of Solar Active Regions and Activity from 24/2100Z to 25/2100Z: Solar activity has been at very low levels for the past 24 hours. There are currently 2 numbered sunspot regions on the disk.

IB.  Solar Activity Forecast: Solar activity is expected to be very low with a slight chance for a C-class flare on days one, two, and three (26 Oct, 27 Oct, 28 Oct).

IIA.  Geophysical Activity Summary 24/2100Z to 25/2100Z: The geomagnetic field has been at quiet to minor storm levels for the past 24 hours. Solar wind speed reached a peak of 676 km/s at 25/1945Z. Total IMF reached 10 nT at 25/0157Z. The maximum southward component of Bz reached -8 nT at 25/0206Z. Electrons greater than 2 MeV at geosynchronous orbit reached a peak level of 1178 pfu.

IIB.  Geophysical Activity Forecast: The geomagnetic field is expected to be at quiet to minor storm levels on day one (26 Oct) and quiet to active levels on days two and three (27 Oct, 28 Oct).

III.  Event probabilities 26 Oct-28 Oct
Class M    01/01/01
Class X    01/01/01
Proton     01/01/01
PCAF       green

IV.  Penticton 10.7 cm Flux
Observed           25 Oct 079
Predicted   26 Oct-28 Oct 079/078/077
90 Day Mean        25 Oct 082

V.  Geomagnetic A Indices
Observed Afr/Ap 24 Oct  013/014
Estimated Afr/Ap 25 Oct  022/028
Predicted Afr/Ap 26 Oct-28 Oct  019/024-013/016-010/012

VI.  Geomagnetic Activity Probabilities 26 Oct-28 Oct
A.  Middle Latitudes
Active                40/30/25
Minor Storm           25/15/10
Major-severe storm    05/05/01
B.  High Latitudes
Active                15/15/20
Minor Storm           30/25/20
Major-severe storm    45/35/20