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Area forecast discussion 
National Weather Service Jackson MS
330 am CDT Monday Jul 14 2014

Short through Tuesday night...early morning water
vapor imagery showed the circulation around a closed low dropping
south over northern Minnesota and the circulation around the middle
level ridge over our region. The closed low will swing across the
Great Lakes region during the short term and help deepen an upper
level trough over the northeast half of the Continental U.S. That will support
a cold front moving across our County Warning Area Tuesday. The middle level ridge over
our region will break down today as the upper level trough to our
north deepens and the resulting lower heights over our region
combined with our moist airmass and daytime heating will lead to a
greater coverage of showers and thunderstorms this afternoon. Latest
surface analysis showed a stalled front across southern Missouri and
back over the Southern Plains while ridging from the western
Atlantic nosed west over the northern Gulf. The resulting low level
flow will help maintain low to middle 70 dew points and precipitable waters between
1.75-2.0 inches today. It will be warm today as sites top out
92-95f. The warmer temperatures will aid convection this afternoon
in the south and models suggest ongoing convection along the stalled
front dropping south toward our Highway 82 corridor. A few strong
thunderstorms with wind gusts of 40-50mph and locally heavy rain
that have developed along and ahead of the boundary may drop into
our Highway 82 corridor this evening. There will likely be a
decrease in activity this evening with the loss of daytime heating
but the actual cold front will drop into our northern zones by
sunrise Tuesday morning and additional activity is expected along
and just ahead of the front. The NAM is the slowest but model
consensus is that the cold front should be near the Interstate 20
corridor by noon and push south of our County Warning Area early Tuesday evening.
A few strong thunderstorms with locally heavy rainfall will be
possible ahead of the cold front Tuesday afternoon across the
southern half of our County Warning Area. Cooler and drier air will filter into the
County Warning Area in the wake of the front Tuesday night lowering dew points into
the 50s and precipitable waters below three quarters of an inch by sunrise
Wednesday. Wednesday morning lows are expected to be below normal
and in the lower 60s in the north. /22/

Long term...Wednesday through next Monday...a cooler drier airmass
will reside over the forecast area Wednesday into Thursday in the
wake of the cold front. Unfortunately this will be short-lived as
moisture begins to increase late Thursday and over the upcoming

A shortwave will swing east across the nation's middle-section and lift
north into the Great Lakes region Friday into the weekend. This
will send a weak surface low and front into the region where it's
currently prognosticated by models to hang up over the forecast area...with
northwest flow forecast to prevail aloft across the lower
Mississippi River valley. This scenario will bring rain chances
back into the forecast from late Thursday and at least through the
remainder of the forecast Monday.

Temperatures during the period will again begin on the cool side for
this time of year...highs in the middle to upper 80s Wednesday and
Thursday with upper 50s to middle 60s for lows Wednesday night. moisture increases...temperatures will climb back into
the lower 90s each afternoon heading into and through the
weekend...with lows each night struggling to fall out of the middle
70s. Afternoon convection will likely play a role in keeping highs
down a bit from the current forecasted highs...but overall hot and
humid conditions will prevail Friday through next Monday. /19/


Aviation...some MVFR visibilities were being observed at 08z and MVFR-IFR
visibilities will be possible 09-13z. After 13z VFR conditions will resume areawide
until the afternoon. Lower flight categories can be expected this afternoon in
vcty of isolated rain showers/thunderstorms and rain activity that will occur mainly in the
north and south. Widespread convection will develop overnight in the
north and Tuesday along a cold front that will approach the Highway 82
corridor by 12z and move across the area through Tuesday evening. /22/


Preliminary point temps/pops...
Jackson 94 73 88 62 / 11 71 59 18
Meridian 94 73 88 62 / 11 71 63 24
Vicksburg 94 72 88 60 / 11 58 42 17
Hattiesburg 93 75 90 67 / 27 26 68 39
Natchez 93 74 89 63 / 22 30 60 18
Greenville 95 73 85 60 / 13 77 29 9
Greenwood 95 72 85 58 / 18 83 30 10


Jan watches/warnings/advisories...



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