Joint USAF/NOAA Solar Geophysical Activity Report and Forecast 15 December 2015

Joint USAF/NOAA Solar Geophysical Activity Report and Forecast
SDF Number 349 Issued at 2200Z on 15 Dec 2015

IA. Analysis of Solar Active Regions and Activity from 14/2100Z to 15/2100Z: Solar activity has been at very low levels for the past 24 hours. There are currently 4 numbered sunspot regions on the disk.

IB. Solar Activity Forecast: Solar activity is likely to be low with a slight chance for an M-class flare on days one, two, and three (16 Dec, 17 Dec, 18 Dec).

IIA. Geophysical Activity Summary 14/2100Z to 15/2100Z: The geomagnetic field has been at quiet to minor storm levels for the past 24 hours. Solar wind speed, as measured by the ACE spacecraft, reached a peak speed of 612 km/s at 15/0807Z. Total IMF reached 10 nT at 14/2104Z. The maximum southward component of Bz reached -10 nT at 14/2104Z. Electrons greater than 2 MeV at geosynchronous orbit reached a peak level of 122 pfu.

IIB. Geophysical Activity Forecast: The geomagnetic field is expected to be at quiet to active levels on day one (16 Dec) and quiet to unsettled levels on days two and three (17 Dec, 18 Dec).

III. Event probabilities 16 Dec-18 Dec
Class M 10/10/10
Class X 01/01/01
Proton 01/01/01
PCAF green

IV. Penticton 10.7 cm Flux
Observed 15 Dec 119
Predicted 16 Dec-18 Dec 120/120/125
90 Day Mean 15 Dec 108

V. Geomagnetic A Indices
Observed Afr/Ap 14 Dec 015/020
Estimated Afr/Ap 15 Dec 015/017
Predicted Afr/Ap 16 Dec-18 Dec 011/012-007/008-007/008

VI. Geomagnetic Activity Probabilities 16 Dec-18 Dec
A. Middle Latitudes
Active 15/10/10
Minor Storm 05/05/01
Major-severe storm 01/01/01
B. High Latitudes
Active 20/15/25
Minor Storm 30/20/30
Major-severe storm 25/15/10