Joint USAF/NOAA Solar Geophysical Activity Report and Forecast 31 December 2013

Joint USAF/NOAA Solar Geophysical Activity Report and Forecast
SDF Number 365 Issued at 2200Z on 31 Dec 2013

IA. Analysis of Solar Active Regions and Activity from 30/2100Z to
31/2100Z: Solar activity has been at low levels for the past 24 hours.
The largest solar event of the period was a C8 event observed at
31/1150Z. There are currently 8 numbered sunspot regions on the disk.

IB. Solar Activity Forecast: Solar activity is expected to be low with
a chance for M-class flares and a slight chance for an X-class flare on
days one, two, and three (01 Jan, 02 Jan, 03 Jan).

IIA. Geophysical Activity Summary 30/2100Z to 31/2100Z: The geomagnetic
field has been at quiet levels for the past 24 hours. Solar wind speed,
as measured by the ACE spacecraft, reached a peak speed of 426 km/s at
31/0012Z. Total IMF reached 6 nT at 31/0605Z. The maximum southward
component of Bz reached -4 nT at 31/0745Z.

IIB. Geophysical Activity Forecast: The geomagnetic field is expected
to be at quiet to unsettled levels on days one and three (01 Jan, 03
Jan) and quiet to minor storm levels on day two (02 Jan).

III. Event probabilities 01 Jan-03 Jan
Class M 40/40/40
Class X 10/10/10
Proton 05/05/05
PCAF green

IV. Penticton 10.7 cm Flux
Observed 31 Dec 145
Predicted 01 Jan-03 Jan 150/150/155
90 Day Mean 31 Dec 144

V. Geomagnetic A Indices
Observed Afr/Ap 30 Dec 002/002
Estimated Afr/Ap 31 Dec 005/005
Predicted Afr/Ap 01 Jan-03 Jan 009/010-014/018-011/010

VI. Geomagnetic Activity Probabilities 01 Jan-03 Jan
A. Middle Latitudes
Active 20/30/20
Minor Storm 05/10/05
Major-severe storm 01/01/01
B. High Latitudes
Active 20/15/20
Minor Storm 30/25/30
Major-severe storm 25/40/25