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Area forecast discussion 
National Weather Service Jackson MS
issued by National Weather Service Huntsville Alabama
1117 am CST Tuesday Dec 1 2015

the surface wind shift has cleared all but the southeast corner of
Mississippi, roughly from Meridian NAS to McComb as of 16z.
Postfrontal precipitation continues across a large swath of the area behind
the front, with another band of rain occurring along the 850 mb front
across northern Mississippi and southeastern Arkansas. Temperatures
are in the middle-60s ahead of the front, middle-50s for most of the area,
and around/lower 50s close to the 850mb front.

Short-term models are in good agreement with continuing categorical
probability of precipitation across eastern and central MS, but a slight bump in probability of precipitation is
warranted farther to the north where rain may be a little more
persistent along the 850 mb front. Otherwise, including isolated
thunderstorms still looks reasonable, as model soundings indicate
steeper middle-level lapse rates evolving through the afternoon.



Previous discussion... /issued 302 am CST Tuesday Dec 1 2015/

Short through Wednesday night...WV imagery this
morning continues to show the warm advection moisture fetch
originating over the Pacific and streaming across northern
Mexico...Texas and into the lower MS River Valley. Also...upper level
cold core continues to spin over the northern plains.

At the surface...somewhat reinvigorated cold front has begun moving
back through the area and was located along a tup...Jan...esf line
at 08z. While the majority of the precipitation occurring this
morning is due to the isentropic ascent over the cool airmass behind
the front...some light showers have formed in the moisture convergent
area along and ahead of the cold front.

Some of the elevated precipitation is also occurring in the form of
thunderstorms over the Delta Region. GFS bufr data is showing a maul
from 700-650 mb which is creating some elevated cape. This along
with the degree of forcing has allowed for the convective
development. Bufr data is indicating that these decent middle level
lapse rates will continue through the course of the day. Thus...should
continue to see isolated thunder embedded in the widespread rains
that develop.

While widespread isentropic ascent will lead to more rain across the
area today...veering winds aloft will finally bring an end to the
rain beginning tonight over the Delta Region and elsewhere through
the course of the day Wednesday. Skies will clear rather quickly
behind the ending rain Wednesday afternoon with clear skies expected
by Wednesday night.

With clear skies and the drier airmass in place by Wednesday
night...temperatures will fall off rapidly during the evening and settle in
the 30s by Thursday morning. With low to middle 30s being possible over
the NE third...areas of frost may be seen in these areas around dawn

Long term...Thursday through next Monday...overall pleasant and
seasonal middle-fall conditions will exist across the region late in
the work week into the upcoming weekend. Cooler drier air will
continue to advect into the forecast area Thursday into Friday as
high pressure builds into the lower Mississippi River valley from
the west. Under sunny skies...highs both Thursday and Friday will
only climb into the middle and upper 50s. Lows Thursday night and
Friday night will fall into the 30s under mostly clear skies.

High pressure shifting east of the region during the weekend will
cause conditions to slightly warm. With mostly clear skies Saturday
and Saturday night...highs will range from the upper 50s to middle
60s...and lows will range from the upper 30s to lower 40s. Both
models agree with keeping Sunday dry and a few degrees warmer
compared to Saturday. The forecast will represent this as clouds
increase a bit during the day and highs peak in the low to middle

Currently...not a lot of confidence exists in the forecast from
Sunday night through Monday night as some timing and evolution
issues exist between the European model (ecmwf) and GFS in regards to the next system
that's prognosticated to affect the region. Therefore...i'll stick with
persistence in the forecast...which currently resides with the European model (ecmwf)
solution. This will keep some small rain chances in the forecast
from early Monday morning through Monday night as a weak disturbance
pushes east through the region. /19/

Aviation...widespread rainy conditions will lead to IFR ceilings and
MVFR visibilities through 18z. Thereafter...ceilings will rise to MVFR...but the
rain and fog will continue to obstruct visibilities. After 02/00z...
conditions will begin improving from the northwest with VFR conditions
returning to glh by this time./26/


Preliminary point temps/pops...
Jackson 57 48 59 37 / 96 69 28 7
Meridian 65 50 57 35 / 97 96 38 9
Vicksburg 56 47 60 39 / 87 50 19 7
Hattiesburg 68 53 59 37 / 73 71 30 9
Natchez 58 49 60 38 / 85 66 25 8
Greenville 53 43 58 35 / 40 21 8 6
Greenwood 56 44 58 35 / 65 32 13 6


Jan watches/warnings/advisories...



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