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000
FXXX12 KWNP 050031
DAYDIS

:Product: Forecast Discussion
:Issued: 2013 Dec 05 0030 UTC
# Prepared by the US Dept. of Commerce, NOAA, Space Weather Prediction Center
# Product description and SWPC contact on the Web
# http://www.swpc.noaa.gov/wwire.html
#
#             Forecast Discussion
#
Solar Activity

.24 hr Summary...
Solar activity has been at low levels for the past 24 hours.
The largest solar event of the period was a C6 flare observed at
04/0056 UTC from a region beyond the east limb. This same region was
responsible for an additional C6 flare at 04/2037 UTC. Region 1913
(S14W84, Dao/beta) exhibited slight growth and was responsible for a
C4/Sf flare that occurred at approximately 04/0458 UTC. An associated
coronal mass ejection was observed in LASCO/C2 imagery at 04/0536 UTC.
Analysis indicated that the ejecta had a westward trajectory and was not
determined to be Earth-directed. The other six numbered sunspot regions
displayed an overall trend of stability or slight decay. Region 1909
(S17W20, Ekc/beta-gamma) continued as the most magnetically complex
region but has yet to produce any significant flare activity. New Region
1916 (S14E19, Bxo/beta) was numbered. There were no Earth-directed
coronal mass ejections observed in satellite imagery during the period.

.Forecast...
Solar activity is expected to be at low levels with a slight chance for
M-class flares (NOAA Scale R1-R2, Minor-Moderate) for the forecast
period (05-07 Dec).

Energetic Particles

.24 hr Summary...
The greater than 2 MeV electron flux at geosynchronous orbit was at
normal levels. The greater than 10 MeV proton flux at geosynchronous
orbit was at background levels.

.Forecast...
The greater than 2 MeV electron flux at geosynchronous orbit is expected
to be at normal to moderate levels for the forecast period (05-07 Dec).
The greater than 10 MeV proton flux at geosynchronous orbit is expected
to remain at background levels (below S1-Minor) for the forecast period
(05-07 Dec).

Solar Wind

.24 hr Summary...
Solar wind parameters, as measured by the ACE spacecraft, indicated
background conditions. Solar wind speed reached a peak of 430 km/s at
04/0539 UTC. Total IMF reached 8 nT at 04/0239 UTC. The maximum
southward component of Bz reached -6 nT at 04/0349 UTC. Phi angle began
the period in a predominately positive (away) orientation, but
oscillated into a negative (towards) orientation for brief periods.

.Forecast...
Solar wind conditions are expected to remain at background levels for
day one (05 Dec). Day two (06 Dec) should see the onset of
a positive-polarity, coronal hole high-speed stream (CH HSS) late in the
day and continue into day three (07 Dec).

Geospace

.24 hr Summary...
The geomagnetic field was quiet.

.Forecast...
The geomagnetic field is expected to be at quiet levels on day one (05
Dec), quiet to unsettled levels on day two (06 Dec) in
response to the onset of a positive-polarity CH HSS, and quiet to active
levels on day three (07 Dec) as CH HSS effects continue.