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FXXX12 KWNP 181230

:Product: Forecast Discussion
:Issued: 2014 Dec 18 1230 UTC
# Prepared by the US Dept. of Commerce, NOAA, Space Weather Prediction Center
# Product description and SWPC contact on the Web
#             Forecast Discussion
Solar Activity

.24 hr Summary...
Solar activity was at moderate levels during the period. Region 2241
(S10E11, Ekc/beta-gamma-delta) produced the largest flare of the period,
an M1/1n flare at 17/1901 UTC, as well as a couple of high level C-class
flares. This region continued to show growth and maintained its delta
magnetic configuration across an east-west polarity inversion line
during the period. Region 2242 (S18W09, Ekc/beta-gamma-delta) remained
one of the most active regions, also producing multiple C-class events,
the largest being a C7/Sf event at 17/2126 UTC. It too, continued to
exhibit growth in its overall areal coverage and maintained its delta
magnetic configuration. The remaining regions on the visible disk
remained stable and mostly inactive. No Earth directed coronal mass
ejections (CMEs) were observed during the period.

Solar activity is expected to be at moderate (R1-R2/Minor-Moderate)
levels for the next three days (18-20 Dec) as Regions 2241 and 2242
continue to grow in areal coverage as well as maintain complex magnetic
structures. There is also a chance for an isolated X-class event
(R3-Strong) during the forecast period.

Energetic Particle

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

The greater than 2 MeV electron flux is expected to be at normal to
moderate levels for the forecast period (18-20 Dec). There is a slight
chance for a greater than 10 MeV proton event (S1-Minor) due to the
potential for a proton producing solar event from Regions 2241 or 2242.

Solar Wind

.24 hr Summary...
The solar wind parameters, measured at ACE, continued to reflect normal
ambient background levels. Solar wind speeds were steady near 390 km/s,
the total field fluctuated slightly between 5 nT and 7 nT, and the Bz
component ranged between +/- 7 nT. Phi angle remained unchanged in a
primarily positive (away) orientation for most of the period.

Solar wind conditions are expected to remain at ambient background
levels for the majority of days one and two (18-19 Dec). Disturbed solar
wind conditions are anticipated beginning late on 19 Dec due to the
arrival of the CME associated with the M8 flare observed on 17 Dec.


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

The geomagnetic field is expected to be quiet to unsettled (below
G1-Minor) for the majority of days one and two (18-19 Dec). Unsettled to
active conditions are expected to begin late on 19 Dec, with a chance
for isolated minor storm periods (G1-Minor) due to the arrival of the
CME associated with the M8 flare observed on 17 Dec.

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