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Area forecast discussion 
National Weather Service Jackson MS
400 am CDT Friday Aug 1 2014

Short through Saturday night...weak disturbances
embedded in continued west northwest flow addition to an
inverted trough/very weak surface low currently analyzed over east
central Texas...will continue to be the primary culprits in keeping
rain chances over the forecast area through much of the short term
period. The area of showers currently seen on radar over in my
western zones will continue to move east southeast and deeper into
the County Warning Area this morning...but should gradually break-up the further
east it gets as it encounters a somewhat drier/more stable
atmosphere. Models support this solution and this trend is already
being observed on radar this morning. Thus...better rain chances are
forecast today to be generally along and west of the Interstate 55
corridor today and tonight. Showers will be more of the isolated to
scattered variety east of Interstate 55.

Again...not much will change in terms of the setup for Saturday.
The previously mentioned surface feature will slide a little further
east into western Louisiana Saturday. Instability will also be a
bit better compared to recent days. Therefore...showers a few
thunderstorms will be possible...mainly during the afternoon hours.
Most of this activity will dissipate during the late afternoon
hours...but a few showers could hang on overnight Saturday and into
early Sunday...particularly across my southwest.

Once again...clouds will again be the main player in keeping highs a
few degrees below normal both today and Saturday. Obviously this
will be furthered in locations that observe rain. Highs today will
Range Peak in the low to middle 80s but will be a tad warmer on
Saturday as they generally top out in the middle and upper 80s. Lows
both tonight and Saturday night will remain on the mild side and
only slip into the middle and upper 60s. /19/

Long term...Sunday through Friday...the upper level trough will
still be lingering over our region Sunday although weakening through
the day. Surface high pressure will be centered north of our area
and help filter in a little drier air into our County Warning Area on a north to
northeast wind. Precipitable waters will range from an inch and half north to near
two inches in the south Sunday morning and drop below an inch and a
half north of Interstate 20 by Monday morning. Greatest probability of precipitation Sunday
will be carried over the southern half of the area. Precipitable waters will drop
further by Tuesday morning and change very little for Wednesday.
Greatest probability of precipitation Monday through Wednesday will be carried over our
southeast zones with very little chance for rain expected over our
Delta Region. Mainly diurnally driven rain chances are expected
Monday through Wednesday. Afternoon maximum temperatures will be a
little below normal Sunday in the upper 80s and then be near normal
in the lower 90s Monday through Wednesday. Morning lows will
continue below normal Tuesday and Wednesday mornings in the upper
60s and be near normal in the lower 70s at most locations Thursday
morning. There are some differences in the models with Thursday and
Friday. The European model (ecmwf) is warmer and drier than the GFS. Both models
indicate that surface ridging will strengthen along the Gulf Coast
and the resulting southerly flow will increase low level moisture.
The GFS keeps lower heights aloft over our region while the European model (ecmwf)
strengthens middle level ridging over the Gulf states. Last night's
model run featured another shortwave dropping out of the northern
plains to the Great Lakes region by Friday morning. This feature is
weaker and remains farther north in the latest run. A trend to above
normal temperatures with lower rain chances looks to be the trend
for the end of week. /22/


Aviation...VFR conditions should prevail at most taf sites through
the course of Friday and through Friday night. A brief bout of
mainly MVFR visibilities could be observed through the course of the
period where more moderate rainfall is observed from any shower
activity. Winds today will again have a northerly component between
5-8 knots...and gradually subside to light to calm later this
evening. /19/


Preliminary point temps/pops...
Jackson 86 68 88 68 / 55 36 40 31
Meridian 87 67 88 69 / 32 21 47 34
Vicksburg 84 67 87 67 / 68 38 36 24
Hattiesburg 87 68 90 71 / 44 19 53 35
Natchez 84 68 86 69 / 100 33 37 26
Greenville 80 67 86 68 / 59 21 26 11
Greenwood 83 66 87 67 / 47 20 31 16


Jan watches/warnings/advisories...



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