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Area forecast discussion 
National Weather Service Jackson MS
331 am CDT Tuesday Sep 1 2015

Short through Wednesday night... latest satellite
vapor imagery a weak shear axis which extended from the Southern
Plains to the Ohio Valley. Along the shear axis a weak closed low
was noted over southern Texas...western Arkansas and in the Ohio
Valley. Area radars were picking up some northward moving isolated
convection over south central Louisiana. High debris clouds were
moving over the County Warning Area from convection off the northwest Gulf. The
region was under large amplitude ridging over the eastern Continental U.S. With
594 dkm high east of Florida. Surface high pressure was centered the
northern Gulf.

925 mb temperatures will be from 25-26c for daily highs in the lower to
middle 90s. Overall light flow at the surface and aloft will keep
moisture levels about the same each day with dewpoints mixing into
the 60s each afternoon. Nightly lows will be mainly in the lower 70s.

Precipitable waters will hold steady across the region ranging from the 1.7 east
to near 2 inches west near the shear axis. The weak shear axis will
be close enough to the County Warning Area to trigger some isolated diurnal
convection in the west for today and for most of the County Warning Area on
Wednesday. So coverage will be limited by midlevel capping and high
pressure centered over the northern Gulf. This is confirmed by the
lack of activity in most of the hi-res models./17/

Long term...Thursday through next Monday...a weak upper low
meandering near the region late in the work week will essentially
become absorbed by another upper level low dropping south along the
East Coast of the United States over the weekend. The result will
be the forecast area becoming wedged between said upper low now
residing along the southeast coast of the U.S. And an amplifying
upper ridge over the Southern Plains and middle-Mississippi River
valley. Meanwhile at the surface...weak high pressure will be in
place...predominately resulting in easterly flow across the region
through much of the period.

All of this equates to typical late Summer hot and humid conditions
existing across the County Warning Area during the long term portion of the
forecast. Highs each afternoon will climb into the 90s...with lows
falling down around 70 each night. Isolated to scattered showers
and storms will develop during the heat of the afternoon...but will
quickly dissipate around sunset each evening as daytime heating is
lost. /19/


Aviation...VFR conds will prevail at most taf sites but some patchy
fog and MVFR visible is possible at some sites 09z-13z. Some middle/high
clouds will move over most taf sites. Light/variable winds
will continue through today./17/


Preliminary point temps/pops...
Jackson 96 71 95 72 / 12 10 18 14
Meridian 94 71 94 72 / 7 10 18 12
Vicksburg 96 71 96 71 / 12 11 19 14
Hattiesburg 96 72 94 73 / 9 10 18 14
Natchez 94 72 93 72 / 15 13 21 14
Greenville 96 71 97 72 / 13 10 17 12
Greenwood 94 71 95 71 / 8 10 10 10


Jan watches/warnings/advisories...


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