Joint USAF/NOAA Solar Geophysical Activity Report and Forecast 24 December 2013

Joint USAF/NOAA Solar Geophysical Activity Report and Forecast
SDF Number 358 Issued at 2200Z on 24 Dec 2013

IA. Analysis of Solar Active Regions and Activity from 23/2100Z to
24/2100Z: Solar activity has been at low levels for the past 24 hours.
The largest solar event of the period was a C1 event observed at
24/1552Z. There are currently 6 numbered sunspot regions on the disk.

IB. Solar Activity Forecast: Solar activity is likely to be low with a
chance for M-class flares on days one, two, and three (25 Dec, 26 Dec,
27 Dec).

IIA. Geophysical Activity Summary 23/2100Z to 24/2100Z: 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 319 km/s at
23/2110Z.

IIB. Geophysical Activity Forecast: The geomagnetic field is expected
to be at quiet to active levels on day one (25 Dec), quiet to unsettled
levels on day two (26 Dec) and quiet levels on day three (27 Dec).

III. Event probabilities 25 Dec-27 Dec
Class M 35/30/30
Class X 01/01/01
Proton 01/01/01
PCAF green

IV. Penticton 10.7 cm Flux
Observed 24 Dec 128
Predicted 25 Dec-27 Dec 130/130/130
90 Day Mean 24 Dec 141

V. Geomagnetic A Indices
Observed Afr/Ap 23 Dec 002/001
Estimated Afr/Ap 24 Dec 002/002
Predicted Afr/Ap 25 Dec-27 Dec 007/010-008/008-006/005

VI. Geomagnetic Activity Probabilities 25 Dec-27 Dec
A. Middle Latitudes
Active 25/20/05
Minor Storm 10/05/01
Major-severe storm 01/01/01
B. High Latitudes
Active 15/15/15
Minor Storm 25/25/15
Major-severe storm 35/25/05