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Area forecast discussion 
National Weather Service Jackson MS
908 PM CST Sat Jan 31 2015

Update...low pressure over the Southern Plains this evening will
head toward Missouri by early Sunday morning. The southerly flow
ahead of this system will draw moisture northward overnight and
eventually spread showers into the western part of the forecast area
late tonight. With the winds staying up and cloud cover in place...do
not anticipate much more of a temperature drop overnight.

Current forecast is in good shape and no update is planned. /SW/

&&

Aviation...clouds will lower late tonight leading to MVFR ceilings at
most sites by 12z and then eventually IFR ceilings after 12z. Visibility will
be reduced to MVFR at times in showers on Sunday. /SW/

&&

Previous discussion... /issued 330 PM CST Sat Jan 31 2015/

Discussion...water vapor imagery showed the circulation around a
closed low over the Baja California peninsula and a potent northern stream
shortwave dropping south from the northern rockies. The closed low
has helped bring some middle and high level clouds to our region today
but will become less of an immediate influence over our area as it
drops south through Sunday. We will see the closed low again by
Wednesday though. On the other hand...the potent shortwave will deepen
as it tracks east and strengthens a surface low noted just east of
The Rockies over Colorado this afternoon. Warm air advection will increase tonight
over our area ahead of the approaching low pressure system that will
drop a strong cold front into our Delta Sunday afternoon. Breezy
south winds will develop ahead of the cold front and help temperatures
climb in the the middle and upper 60s at most locations. Some locations
in the south will reach 70 degrees before the cold front moves
through. By Sunday afternoon precipitable waters will be back above an inch and a
quarter with decent deep layer shear over the region but overall
instability is expected to limit strong storm development. The cold
front will push southeast of our County Warning Area before midnight and gusty
northwest winds will usher in much colder and drier air. There remains
the possibility of a few snow flurries in the northeast as
temperature profiles become cold enough before the precipitation
totally ends. Morning lows will be near freezing while the flurries
fall but no accumulation is expected. The gusty north winds
overnight should help dry the roads but patches of black ice may
form on bridges and overpasses early Monday morning across the
Highway 82 corridor. The shortwave trough will shift east of our County Warning Area
Monday while surface high pressure builds in from the west. North
winds will become lighter through the day but cold air advection will hold highs Monday
in the 40s. The surface high will be centered over our County Warning Area Monday
night allowing for strong radiational cooling. The coldest morning
of the forecast period is expected Tuesday with morning lows in the
middle 20s at most locations. Dry weather is expected Tuesday but the
old closed low will open up as it swings east over southern Texas
Tuesday night and Wednesday. This now shortwave trough will help
develop a surface low off the Texas coast that will track east across
the northern Gulf through Thursday. Rain associated with this low
pressure system is expected to begin moving back into our County Warning Area
Wednesday morning. By Thursday morning the precipitation associated
with this low pressure system should be ending over our southeast
most zones. Models still disagree on the strength and moisture of a
northern stream shortwave trough that will be diving over our County Warning Area on
the heels of the departing Gulf low. The European model (ecmwf) remains dry with this
next shortwave while the GFS and Canadian generate precipitation. This system
bears watching as temperatures look cold enough for some wintry type
precipitation. Have leaned toward the drier European model (ecmwf) with this package.
Cooler and drier weather is expected Friday then continued dry and
warmer Saturday as return flow gets reestablished. /22/

&&

Aviation...
VFR conditions will prevail through this evening although
clouds will thicken ahead of an approaching low pressure system. MVFR
ceilings are expected after 08z and showers will spread across the area
Sunday morning. The cold front will move through glh by 22z and hbg
before 06z Monday. A few thunderstorms will be possible Sunday along and ahead of the
cold front. Gusty southwest winds will develop Sunday ahead of the
cold front shifting to the northwest with frontal passage and remain above
10kts through Sunday night. /22/

&&

Preliminary point temps/pops...
Jackson 48 68 35 45 / 18 88 66 4
Meridian 41 65 36 46 / 6 90 68 6
Vicksburg 50 69 35 45 / 31 94 52 3
Hattiesburg 46 70 41 50 / 15 78 66 3
Natchez 52 70 34 45 / 34 88 58 3
Greenville 47 64 32 41 / 45 97 32 4
Greenwood 48 63 32 42 / 20 97 49 5

&&

Jan watches/warnings/advisories...
MS...none.
La...none.
Arkansas...none.
&&

$$

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