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000
FXXX12 KWNP 060030
DAYDIS

:Product: Forecast Discussion
:Issued: 2013 Dec 06 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 was at low levels for the past 24 hours. The largest
solar event of the period was a C6 flare observed at 05/1743 UTC from
Region 1909 (S17W34, Dai/beta). Region 1909 has shown slight decay in
its intermediate spots during the period. Region 1916 (S14E05, Dao/beta)
produced a C1/Sf at 05/0643 UTC and showed signs of increased magnetic
complexity in its follower spotgroup. A region from around the southeast
limb was responsible for additional C-flare activity including a C5
flare at 05/1459 UTC and a C4 flare at 05/1127 UTC. At the time of this
report this flare producing, unnumbered region had yet to show spots on
the visible disk. A coronal mass ejection (CME) from this region, first
observed in LASCO/C2 imagery at 05/1024 UTC, was analyzed and determined
to be to far around the limb to have any significant effects at Earth.
The CME mentioned in the previous discussion, associated with the large
48 disappearing solar filament in the northern solar hemisphere, was
also determined to be non-geoeffective.

.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 (06-08 Dec).

Energetic Particles

.24 hr Summary...
The greater than 2 MeV electron flux at geosynchronous orbit stayed at
normal levels but came close to breaching the moderate threshold. The
maximum electron flux value measured by the GOES-13 spacecraft was 9.7
pfu on 05/1445 UTC. 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 (06-08 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
(06-08 Dec).

Solar Wind

.24 hr Summary...
Solar wind parameters, as measured by the ACE spacecraft, remained at
background conditions. Solar wind speed reached a peak of 381 km/s at
05/1009 UTC, but remained in the mid 300 km/s range for most of the
period. Total IMF was steady at approximately 5 nT. IMF Bz remained
predominately negative with a maximum southward extent of -4 nT at
05/1009 UTC. Phi angle remained in a predominately positive (away)
orientation throughout the period.

.Forecast...
Solar wind conditions are expected to remain at background levels until
mid to late on day one (06 Dec) as effects from a corotating interaction
region (CIR) followed by the onset of a positive-polarity, coronal hole
high-speed stream (CH HSS) come into play. These effects should prevail
on day two (07 Dec) and begin to wane on day three (08 Dec).

Geospace

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

.Forecast...
The geomagnetic field is expected to be at quiet to unsettled levels on
day one (06 Dec) and quiet to active levels on days two and three (07-08
Dec) as the Earth begins to see evidence of the CH HSS mentioned
earlier.