Joint USAF/NOAA Solar Geophysical Activity Report and Forecast 26 October 2017

Joint USAF/NOAA Solar Geophysical Activity Report and Forecast
SDF Number 299 Issued at 2200Z on 26 Oct 2017

IA.  Analysis of Solar Active Regions and Activity from 25/2100Z to 26/2100Z: 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 (27 Oct, 28 Oct, 29 Oct).

IIA.  Geophysical Activity Summary 25/2100Z to 26/2100Z: The geomagnetic field has been at quiet to active levels for the past 24 hours. Solar wind speed reached a peak of 607 km/s at 26/0357Z. Total IMF reached 6 nT at 26/0103Z. The maximum southward component of Bz reached -5 nT at 26/0848Z. Electrons greater than 2 MeV at geosynchronous orbit reached a peak level of 2154 pfu.

IIB.  Geophysical Activity Forecast: The geomagnetic field is expected to be at quiet to active levels on days one and two (27 Oct, 28 Oct) and quiet to unsettled levels on day three (29 Oct).

III.  Event probabilities 27 Oct-29 Oct
Class M    01/01/01
Class X    01/01/01
Proton     01/01/01
PCAF       green

IV.  Penticton 10.7 cm Flux
Observed           26 Oct 077
Predicted   27 Oct-29 Oct 078/077/077
90 Day Mean        26 Oct 082

V.  Geomagnetic A Indices
Observed Afr/Ap 25 Oct  015/018
Estimated Afr/Ap 26 Oct  017/026
Predicted Afr/Ap 27 Oct-29 Oct  013/016-010/012-007/008

VI.  Geomagnetic Activity Probabilities 27 Oct-29 Oct
A.  Middle Latitudes
Active                30/25/20
Minor Storm           15/10/05
Major-severe storm    05/01/01
B.  High Latitudes
Active                15/20/15
Minor Storm           25/20/25
Major-severe storm    35/20/30