Joint USAF/NOAA Solar Geophysical Activity Report and Forecast 28 December 2013

Joint USAF/NOAA Solar Geophysical Activity Report and Forecast
SDF Number 362 Issued at 2200Z on 28 Dec 2013

IA. Analysis of Solar Active Regions and Activity from 27/2100Z to
28/2100Z: Solar activity has been at low levels for the past 24 hours.
The largest solar event of the period was a C9 event observed at
28/1802Z from Region 1936 (S17E06). There are currently 5 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 (29 Dec, 30 Dec,
31 Dec).

IIA. Geophysical Activity Summary 27/2100Z to 28/2100Z: 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 379 km/s at
28/2040Z. Total IMF reached 8 nT at 28/1620Z. The maximum southward
component of Bz reached -5 nT at 28/2059Z. Protons greater than 10 MeV
at geosynchronous orbit reached a peak level of 5 pfu at 28/2055Z.

IIB. Geophysical Activity Forecast: The geomagnetic field is expected
to be at quiet levels on days one, two, and three (29 Dec, 30 Dec, 31
Dec). Protons greater than 10 Mev are expected to cross threshold on day
one (29 Dec) and have a chance of crossing threshold on day two (30
Dec).

III. Event probabilities 29 Dec-31 Dec
Class M 25/25/25
Class X 01/01/01
Proton 75/50/01
PCAF green

IV. Penticton 10.7 cm Flux
Observed 28 Dec 135
Predicted 29 Dec-31 Dec 135/135/135
90 Day Mean 28 Dec 142

V. Geomagnetic A Indices
Observed Afr/Ap 27 Dec 003/001
Estimated Afr/Ap 28 Dec 002/003
Predicted Afr/Ap 29 Dec-31 Dec 006/005-006/005-006/005

VI. Geomagnetic Activity Probabilities 29 Dec-31 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