Joint USAF/NOAA Solar Geophysical Activity Report and Forecast 27 December 2016

Joint USAF/NOAA Solar Geophysical Activity Report and Forecast
SDF Number 362 Issued at 2200Z on 27 Dec 2016

IA. Analysis of Solar Active Regions and Activity from 26/2100Z to 27/2100Z: Solar activity has been at very low levels for the past 24 hours. There is currently 1 numbered sunspot region 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 (28 Dec, 29 Dec, 30 Dec).

IIA. Geophysical Activity Summary 26/2100Z to 27/2100Z: The geomagnetic field has been at quiet to active levels for the past 24 hours. Solar wind speed reached a peak of 696 km/s at 26/2117Z. Electrons greater than 2 MeV at geosynchronous orbit reached a peak level of 15954 pfu.

IIB. Geophysical Activity Forecast: The geomagnetic field is expected to be at quiet levels on days one and two (28 Dec, 29 Dec) and quiet to active levels on day three (30 Dec).

III. Event probabilities 28 Dec-30 Dec
Class M 01/01/01
Class X 01/01/01
Proton 01/01/01
PCAF green

IV. Penticton 10.7 cm Flux
Observed 27 Dec 074
Predicted 28 Dec-30 Dec 073/072/070
90 Day Mean 27 Dec 080

V. Geomagnetic A Indices
Observed Afr/Ap 26 Dec 015/018
Estimated Afr/Ap 27 Dec 008/010
Predicted Afr/Ap 28 Dec-30 Dec 006/005-006/005-010/012

VI. Geomagnetic Activity Probabilities 28 Dec-30 Dec
A. Middle Latitudes
Active 10/10/35
Minor Storm 01/01/20
Major-severe storm 01/01/05
B. High Latitudes
Active 20/20/10
Minor Storm 20/20/25
Major-severe storm 10/10/50