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000
FXXX12 KWNP 090030
DAYDIS

:Product: Forecast Discussion
:Issued: 2013 Dec 09 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 low. Only low level C-class flares were observed.
Slight growth was observed in the intermediate and trailing spots of
Regions 1916 (S13W37, Eai/beta-gamma) and 1917 (S16E57, Dai/beta). New
Region 1918 (S09E76, Hax/alpha) rotated onto the disk. The rest of the
spotted regions were either stable or in decay.

.Forecast...
Solar activity is expected to be low with a chance for M-class flares
(R1-Minor) for the forecast period (09-11 Dec). The most likely Regions
to produce M-class activity are Regions 1916 and 1917.

Energetic Particle

.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 days 1-2 (09-10 Dec) with high
levels possible on day 3 (11 Dec) due to coronal hole high speed stream
(CH HSS) activity.  The greater than 10 MeV proton flux at
geosynchronous orbit is expected to remain at background levels (below
S1-Minor) for the forecast period (09-11 Dec).

Solar Wind

.24 hr Summary...
Solar wind conditions indicated the onset of a co-rotating interaction
region (CIR) followed by CH HSS and possible transient influence from
the 05 Dec CME. The period began at nominal levels with solar wind
speeds in the 320 to 350 range and total field measurements between 1 nT
and 6 nT. By approximately 07/2114 UTC, a slow increase in total field,
solar wind speed, temperature, and density was observed culminating in a
total field increase of 27 nT at 08/0219 UTC. The Bz component went
southward to a maximum of -24 nT while solar wind speeds were near 500
km/s as the CIR reached its maximum strength.  Solar wind speed
continued near 500 km/s until a reverse shock occurred at 08/0730 UTC.
Solar wind speed increased again to a maximum of about 650 km/s with
total field suddenly decreasing from 10 nT to 5 nT. Phi angle was
variable through the period until approximately 08/0610 UTC when it
moved into a mostly positive (away) sector.

.Forecast...
Solar wind speeds are expected to continue to be enhanced on day 1 (09
Dec) under the influence of a positive polarity CH HSS and remain
elevated into day 2 (10 Dec). A possible glancing blow from the 07 Dec
CME is expected to further enhance solar wind parameters by late on day
1 to early on day 2 (09-10 Dec).

Geospace

.24 hr Summary...
The geomagnetic field was at quiet to major storm levels due to a
combination of CIR, CH HSS, and possible effects from the 05 Dec CME.
Minor to major storm (G1-G2, Minor-Moderate) levels were observed during
08/0000-0300 UTC and 08/0300-0600 UTC periods.

.Forecast...
The geomagnetic field is expected to be at quiet to active levels
with a slight chance for isolated minor storm (G1-Minor) periods on days
1 and 2 (09-10 Dec) due to combined CH HSS and CME effects.