Joint USAF/NOAA Solar Geophysical Activity Report and Forecast 19 April 2016

Joint USAF/NOAA Solar Geophysical Activity Report and Forecast
SDF Number 110 Issued at 2200Z on 19 Apr 2016

IA. Analysis of Solar Active Regions and Activity from 18/2100Z to 19/2100Z: 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 low with a slight chance for an M-class flare on day one (20 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 (21 Apr) and expected to be very low with a slight chance for a C-class flare on day three (22 Apr).

IIA. Geophysical Activity Summary 18/2100Z to 19/2100Z: The geomagnetic field has been at quiet levels for the past 24 hours. Solar wind speed reached a peak of 426 km/s at 18/2350Z. Total IMF reached 6 nT at 19/2024Z. The maximum southward component of Bz reached -4 nT at 19/0141Z. Electrons greater than 2 MeV at geosynchronous orbit reached a peak level of 376 pfu.

IIB. Geophysical Activity Forecast: The geomagnetic field is expected to be at quiet to unsettled levels on day one (20 Apr) and quiet levels on days two and three (21 Apr, 22 Apr). Protons greater than 10 Mev have a slight chance of crossing threshold on day one (20 Apr).

III. Event probabilities 20 Apr-22 Apr
Class M 15/10/01
Class X 05/01/01
Proton 15/05/01
PCAF green

IV. Penticton 10.7 cm Flux
Observed 19 Apr 089
Predicted 20 Apr-22 Apr 085/085/085
90 Day Mean 19 Apr 099

V. Geomagnetic A Indices
Observed Afr/Ap 18 Apr 007/006
Estimated Afr/Ap 19 Apr 004/004
Predicted Afr/Ap 20 Apr-22 Apr 008/008-006/005-006/005

VI. Geomagnetic Activity Probabilities 20 Apr-22 Apr
A. Middle Latitudes
Active 15/15/15
Minor Storm 10/05/05
Major-severe storm 01/01/01
B. High Latitudes
Active 15/15/15
Minor Storm 20/20/20
Major-severe storm 25/20/20