Joint USAF/NOAA Solar Geophysical Activity Report and Forecast 16 April 2017

Joint USAF/NOAA Solar Geophysical Activity Report and Forecast
SDF Number 106 Issued at 2200Z on 16 Apr 2017

IA.  Analysis of Solar Active Regions and Activity from 15/2100Z to 16/2100Z: Solar activity has been at very low levels for the past 24 hours. There are currently 0 numbered sunspot regions on the disk.

IB.  Solar Activity Forecast: Solar activity is expected to be very low with a chance for a C-class flares on days one, two, and three (17 Apr, 18 Apr, 19 Apr).

IIA.  Geophysical Activity Summary 15/2100Z to 16/2100Z: The geomagnetic field has been at quiet levels for the past 24 hours. Solar wind speed reached a peak of 381 km/s at 16/1150Z. Total IMF reached 5 nT at 16/0540Z. The maximum southward component of Bz reached -4 nT at 16/0531Z. Electrons greater than 2 MeV at geosynchronous orbit reached a peak level of 909 pfu.

IIB.  Geophysical Activity Forecast: The geomagnetic field is expected to be at unsettled to minor storm levels on day one (17 Apr), quiet to active levels on day two (18 Apr) and unsettled to active levels on day three (19 Apr).

III.  Event probabilities 17 Apr-19 Apr
Class M    05/05/05
Class X    01/01/01
Proton     01/01/01
PCAF       green

IV.  Penticton 10.7 cm Flux
Observed           16 Apr 075
Predicted   17 Apr-19 Apr 083/088/090
90 Day Mean        16 Apr 078

V.  Geomagnetic A Indices
Observed Afr/Ap 15 Apr  005/004
Estimated Afr/Ap 16 Apr  007/011
Predicted Afr/Ap 17 Apr-19 Apr  014/020-013/015-013/018

VI.  Geomagnetic Activity Probabilities 17 Apr-19 Apr
A.  Middle Latitudes
Active                40/40/40
Minor Storm           20/20/20
Major-severe storm    01/01/01
B.  High Latitudes
Active                10/10/10
Minor Storm           20/25/25
Major-severe storm    55/55/60