Joint USAF/NOAA Solar Geophysical Activity Report and Forecast 5 April 2017

Joint USAF/NOAA Solar Geophysical Activity Report and Forecast
SDF Number 95 Issued at 2200Z on 05 Apr 2017

IA.  Analysis of Solar Active Regions and Activity from 04/2100Z to 05/2100Z: 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 04/2342Z from Region 2645 (S10W53). There are currently 2 numbered sunspot regions on the disk.

IB.  Solar Activity Forecast: Solar activity is likely to be low with a chance for M-class flares and a slight chance for an X-class flare on day one (06 Apr) and expected to be very low with a chance for a C-class flares and a slight chance for an M-class flare on day two (07 Apr) and expected to be very low with a slight chance for a C-class flare on day three (08 Apr).

IIA.  Geophysical Activity Summary 04/2100Z to 05/2100Z: The geomagnetic field has been at quiet to unsettled levels for the past 24 hours. Solar wind speed reached a peak of 489 km/s at 05/2011Z. Total IMF reached 13 nT at 05/1744Z. The maximum southward component of Bz reached -6 nT at 05/0452Z. Electrons greater than 2 MeV at geosynchronous orbit reached a peak level of 210 pfu.

IIB.  Geophysical Activity Forecast: The geomagnetic field is expected to be at quiet to unsettled levels on days one, two, and three (06 Apr, 07 Apr, 08 Apr). Protons greater than 10 Mev have a slight chance of crossing threshold on days one and two (06 Apr, 07 Apr).

III.  Event probabilities 06 Apr-08 Apr
Class M    35/20/01
Class X    10/05/01
Proton     10/10/01
PCAF       green

IV.  Penticton 10.7 cm Flux
Observed           05 Apr 085
Predicted   06 Apr-08 Apr 085/080/075
90 Day Mean        05 Apr 078

V.  Geomagnetic A Indices
Observed Afr/Ap 04 Apr  017/017
Estimated Afr/Ap 05 Apr  007/008
Predicted Afr/Ap 06 Apr-08 Apr  007/008-007/008-007/008

VI.  Geomagnetic Activity Probabilities 06 Apr-08 Apr
A.  Middle Latitudes
Active                15/20/20
Minor Storm           05/05/05
Major-severe storm    01/01/01
B.  High Latitudes
Active                15/15/15
Minor Storm           20/15/20
Major-severe storm    20/15/15