National Weather Service Weather Forecast Office

• Home
• Site Map
• News
• Organization
• Search for: NWS All NOAA 

000
FXXX12 KWNP 100031
DAYDIS

:Product: Forecast Discussion
:Issued: 2013 Dec 10 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 C2 flare observed at 09/1130 UTC from
Region 1917 (S16E45). Region 1916 (S13W51) was the most magnetically
complex region on the solar disk. Regions 1919 (S06W25), 1920 (N12E71),
and 1921 (N06E76) were numbered today. No Earth-directed coronal mass
ejections (CMEs) were detected in satellite imagery during the period.

.Forecast...
Solar activity is expected to be low with a chance for M-class flares
during the period (10-12 Dec). The most likely Regions to produce
M-class activity are Regions 1916 and 1917.

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 day one (10 Dec) with high
levels possible on days two and three (11-12 Dec) due to coronal hole
high-speed stream (CH HSS) influence.  The greater than 10 MeV proton
flux at geosynchronous orbit is expected to remain at background levels
(below S1-Minor) for the forecast period (10-12 Dec).

Solar Wind

.24 hr Summary...
Solar wind parameters during the period displayed typical waning CH HSS
influence. Solar wind speed started the period at approximately 530 km/s
and steadily decreased to end the period at approximately 400 km/s.
Total IMF reached a maximum value of 5 nT at the beginning of the
period. The maximum southward component of Bz reached -3 nT at 09/1443
UTC. Phi angle toggled between positive (away) and negative (towards)
solar sectors.

.Forecast...
Solar wind speed is expected to be slightly enhanced for the first part
of day one (10 Dec) as CH HSS effects continue to wane. A possible
glancing blow from the 07 Dec CME may further enhance solar wind
parameters early on day one (10 Dec). Days two and three (11-12 Dec),
should see a gradual return to nominal background solar wind conditions.

Geospace

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

.Forecast...
The geomagnetic field is expected to be at quiet to active levels on day
one (10 Dec) due to anticipated glancing blow effects from the 07 Dec
CME. Day two (11 Dec) is expected to be quiet to unsettled and day three
(12 Dec) should see a return to quiet levels.