Joint USAF/NOAA Solar Geophysical Activity Report and Forecast 19 December 2013

Joint USAF/NOAA Solar Geophysical Activity Report and Forecast
SDF Number 353 Issued at 2200Z on 19 Dec 2013

IA. Analysis of Solar Active Regions and Activity from 18/2100Z to
19/2100Z: Solar activity has been at low levels for the past 24 hours.
The largest solar event of the period was a C2 event observed at
19/1535Z from Region 1928 (S16W19). There are currently 9 numbered
sunspot regions on the disk.

IB. Solar Activity Forecast: Solar activity is expected to be low with
a chance for M-class flares on days one, two, and three (20 Dec, 21 Dec,
22 Dec).

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,
as measured by the ACE spacecraft, reached a peak speed of 409 km/s at
19/1447Z. Total IMF reached 6 nT at 18/2225Z. The maximum southward
component of Bz reached -5 nT at 19/0034Z.

IIB. Geophysical Activity Forecast: The geomagnetic field is expected
to be at quiet levels on days one, two, and three (20 Dec, 21 Dec, 22
Dec).

III. Event probabilities 20 Dec-22 Dec
Class M 30/30/30
Class X 05/05/05
Proton 01/01/01
PCAF green

IV. Penticton 10.7 cm Flux
Observed 19 Dec 153
Predicted 20 Dec-22 Dec 155/150/145
90 Day Mean 19 Dec 140

V. Geomagnetic A Indices
Observed Afr/Ap 18 Dec 003/003
Estimated Afr/Ap 19 Dec 004/005
Predicted Afr/Ap 20 Dec-22 Dec 005/005-005/005-005/005

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