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Area forecast discussion 
National Weather Service Jackson MS
345 am CST Tuesday Jan 27 2015

Short through Wednesday night...continued dry through
the period with above normal daytime temperatures and after
tonight...above normal morning lows. Early morning surface analysis
had a 1012mb low centered over the Tennessee Valley. This low will
continue tracking southeast today and drag a weak dry cold front
across our County Warning Area this morning reinforcing the dry airmass over our
region. In the wake of the cold front...a light north wind is
expected but cold air advection will be weak and near full insolation will allow
temperatures to top out in the 60s this afternoon. A surface high
will become centered northeast of our County Warning Area tonight but the resulting
north winds should be light enough to decouple and lend to strong
radiational cooling of our dry airmass. Wednesday morning lows will
be in the 30s areawide. The surface high will shift to the East
Coast Wednesday resulting in light return flow over our region by
late afternoon. The amplified ridging to our west today will dampen
and shift over our County Warning Area Wednesday. The ridging surface and aloft will
maintain decent insolation and allow temperatures to climb into the
60s again over much of the area. A shortwave and associated surface
low will move over the middle Mississippi Valley by Thursday morning.
The resulting increased pressure gradient should be enough to
maintain some mixing Wednesday night over our County Warning Area lending to above
normal morning lows in the 40s. /22/

Long term...Thursday through next Tuesday...a weak middle/upper level
disturbance passing to the northeast of the region...will cause a
cold front to shift through the forecast area Thursday afternoon
through Thursday night. This will bring some clouds back into the
region...along with some small rain chances...primarily over the
northeast portion of the County Warning Area. Behind this front...cooler drier air
will filter back into the forecast area Friday. After highs ranging
from the middle 60s to lower 70s Thursday...highs Friday afternoon will
be noticeably cooler as they generally range in the 50s. Lows
Thursday night will range from the middle 30s to middle 40s and be in the
30s Friday night.

Rain chances begin increasing through the day Saturday...with the
best rain chances currently expected Sunday into Sunday night. With
a split flow pattern aloft residing over much of the Country...West
southwest flow over the southeast United States will cause Pacific
moisture aloft to increase across the lower Mississippi River
valley. Through the course of the weekend...another middle/upper
trough is prognosticated to dig southeast across the nation's
mid-section...cutting off a middle/upper low near Baja California California.
This digging currently prognosticated to cause a surface low to
develop west of the forecast area...which in turn will drag a cold
front into and through the County Warning Area Sunday afternoon into Sunday night as
the surface low races northeast. Though this is still some 5-6 days
out...there are some signals that this scenario could bring some
heavy rainfall potential to the region during the Sunday/Sunday
night timeframe. This will obviously continue to be monitored over
the coming days.

Cooler drier air will filter into the region behind the cold front
Monday into Tuesday. Models really begin to struggle during this
time with how to resolve the before mentioned closed low over the
Desert Southwest. The more aggressive GFS wants to maintain a
fairly deep middle/upper low up into southwest Texas...bringing more
rain into the forecast area Tuesday. While the European model (ecmwf)...weakens the
low to merely an open wave and keeps any rain associated with it out
over the Gulf of Mexico. /19/


Aviation...VFR conditions will prevail through Wednesday. A weak dry
cold front will move through the area this morning bringing a wind
shift to the northwest. Light north winds tonight will become
easterly by Wednesday morning and then southerly by late Wednesday
afternoon. /22/


Preliminary point temps/pops...
Jackson 63 37 63 44 / 0 0 0 3
Meridian 63 32 60 37 / 0 0 0 3
Vicksburg 65 37 66 48 / 0 0 0 3
Hattiesburg 67 37 64 40 / 0 0 0 3
Natchez 65 39 66 48 / 0 0 0 3
Greenville 62 36 62 47 / 0 0 0 8
Greenwood 60 33 61 45 / 0 0 0 8


Jan watches/warnings/advisories...



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