Joint USAF/NOAA Solar Geophysical Activity Report and Forecast 1 April 2017

Joint USAF/NOAA Solar Geophysical Activity Report and Forecast
SDF Number 91 Issued at 2200Z on 01 Apr 2017

IA.  Analysis of Solar Active Regions and Activity from 31/2100Z to 01/2100Z: Solar activity has been at low levels for the past 24 hours. The largest solar event of the period was a C3 event observed at 01/1956Z from Region 2644 (N12W52). There are currently 4 numbered sunspot regions on the disk.

IB.  Solar Activity Forecast: Solar activity is expected to be low with a slight chance for an M-class flare on days one, two, and three (02 Apr, 03 Apr, 04 Apr).

IIA.  Geophysical Activity Summary 31/2100Z to 01/2100Z: The geomagnetic field has been at quiet to active levels for the past 24 hours. Solar wind speed reached a peak of 682 km/s at 31/2104Z. Total IMF reached 5 nT at 01/1038Z. The maximum southward component of Bz reached -4 nT at 01/0958Z. Electrons greater than 2 MeV at geosynchronous orbit reached a peak level of 41365 pfu.

IIB.  Geophysical Activity Forecast: The geomagnetic field is expected to be at quiet to active levels on days one, two, and three (02 Apr, 03 Apr, 04 Apr).

III.  Event probabilities 02 Apr-04 Apr
Class M    20/20/20
Class X    05/05/05
Proton     01/01/01
PCAF       green

IV.  Penticton 10.7 cm Flux
Observed           01 Apr 101
Predicted   02 Apr-04 Apr 105/102/100
90 Day Mean        01 Apr 077

V.  Geomagnetic A Indices
Observed Afr/Ap 31 Mar  021/025
Estimated Afr/Ap 01 Apr  016/020
Predicted Afr/Ap 02 Apr-04 Apr  014/018-014/015-011/012

VI.  Geomagnetic Activity Probabilities 02 Apr-04 Apr
A.  Middle Latitudes
Active                20/20/20
Minor Storm           05/05/05
Major-severe storm    01/01/01
B.  High Latitudes
Active                15/15/15
Minor Storm           15/15/15
Major-severe storm    10/15/10