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Area forecast discussion...updated 
National Weather Service Jackson MS
502 am CST Monday Dec 29 2014

Short term...a dreary/cool forecast is on tap for today...but if
you are hoping for a period to dry out...later today will be the
start of a drying period that looks to linger into Thursday. The steady
light rain has exited to the east and what is left is cloudy/damp
conditions. There remains enough low level moisture and isentropic
lift in place (thanks to some caa) to support patchy/areas of
drizzle. This drizzle doesn't look to last all day...but mainly for
the morning hours and then progress eastward before the depth of low
level moisture is low enough to end the drizzle. Aside from the
morning drizzle...clouds/temps will be the main focus as we go into
Tuesday. While various models differ on where/when the low clouds will
exist or dissipate...there seems to be enough signal to lean more
heavily on the solution that keeps clouds around longer. I expect
nearly all of the County Warning Area to remain cloudy well into tonight and for
clouds not to break up until later on Tuesday. What may help on Tuesday is
that a more established cold air advection regime will get going as the southern
fringe of the Arctic high sinks into the plains. Low level northerly
winds will increase as the colder airmass gets into the region.

Look for high temperatures to be below average with 40s and 50s the range. The
cooler day in the short term looks to be Wednesday when highs may struggle
to exceed 50 for much of the area. Look for low temperatures to be tempered
by clouds tonight...but turn colder for Tuesday-Wednesday nights. A couple
periods of subfreezing conditions are expected. Overall...raw guidance
temperatures seemed to fit the situation well and were heavily used. /Cme/

Long term...a cold airmass passes through Wednesday making for a
cold night to celebrate on new year's evening. Temperatures across the
area should be in the lower to middle 20s. However clouds may be
factor...still expecting it to be cold. Conditions quickly change on
Thursday. The next upper trough drops into The Four Corners and pumps
a good amount of Pacific moisture into the region. There seemed to be
some disagreement in the models on the timing of the rain. Stuck with
the guidance...but it looks like the rain may be delayed a period. Either
way the weekend will be wet. Models were not showing much instability
over the County Warning Area...however there was plenty over the Gulf. A low level
jet was also expected to move into the area on Saturday and there
were some weak lapse rates also. The wave moves out Sunday and a
ridge moves in Monday and maintains through middle week. Near normal
temperatures were expected for much of the period.

With the County Warning Area in the warm sector ahead of the system for the weekend
and a good amount of moisture flowing into the region...will be
interested to see if the models will shift the instability from over
the Gulf inland as we get closer to the weekend. For now the severe weather potential statement
remains clear.


Aviation...look for a combination of IFR/LIFR conditions to linger
into midday for most areas. These restrictions will be mainly from
ceilings...but look for lower visible due to -dz through sunrise and
possibly lingering to 16z across eastern areas. Clouds will be slow
to break up and expect ceilings to linger well into the overnight
with a decent chance they will linger into Tuesday. At this time...look
for ceilings to trend to MVFR after 19-21z but that could get pushed
back as some IFR ceilings may linger. /Cme/


Preliminary point temps/pops...
Jackson 50 42 51 31 / 16 0 0 0
Meridian 54 43 53 30 / 17 0 0 0
Vicksburg 49 39 49 30 / 12 0 0 0
Hattiesburg 59 48 56 33 / 15 0 0 0
Natchez 49 42 51 31 / 11 0 0 0
Greenville 46 34 47 29 / 10 0 0 0
Greenwood 49 37 48 28 / 13 0 0 0


Jan watches/warnings/advisories...



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