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Area forecast discussion 
National Weather Service Jackson MS
419 am CDT sun Jul 13 2014

Short through Monday will be fairly
similar to Saturday but with the potential for a little more
convection in the south and highs slightly warmer. The upper ridge
that is present over the region and that kept convection suppressed
yesterday will remain for some of the day. As the day progresses...
the upper ridge should begin to retreat back to the west in response
to a closed low dropping out of Canada and deepening a large scale
trough. As highs reach into the middle 90s...a little more coverage of
showers and storms should occur given a moist airmass in place
(characterized by precipitable water values around 1.6-1.9 inches). This looks to
primarily occur south of I-20 as locations to the north will still
be influenced by the upper ridge. Any convection that develops
should diminish with loss of daytime heating.

Warm conditions will continue on Monday as sites top out around
92-95 degrees. Mav guidance was a bit robust in terms of highs and
have lowered these a few degrees across the board as an increase in
cloud cover....less ridging and better coverage of showers/storms
should allow temperatures to be lower than previous days. As the
closed low drops further south into the Great Lakes region...the
large longwave trough will dig further south into the mid-south. The
lower heights...along with daytime heating and precipitable water values nearing 2
inches...will create a good environment for more afternoon showers
and storms. Storms could linger into the overnight period as a cold
front drops south into the region. Vertical totals are not too bad
around 26c and deep layer shear increases to around 20-25kts by 12z.
This could support some stronger storms particularly in the Highway
82 corridor. Overnight lows through the period will be warm in the
upper 60s/lower 70s. /28/

Long term...Tuesday through Sunday...models are in a little better
agreement than last night's run with the amplifying upper level
trough and cold front that will move over our County Warning Area Tuesday and bring
widespread rain. A large amplitude trough emanating from a closed
low over the northern Great Lakes region Tuesday morning will
support a cold front dropping into the Highway 82 corridor Tuesday
morning that is now expected to push south of our County Warning Area by Wednesday
morning. Model consensus stalled the front across our County Warning Area in last
night's run. Cloud cover and rainfall ahead of the cold front is
expected to limit instability but with precipitable waters around two inches...
MLCAPES 1500-2000j/kg and -7 lifted indice's by noon a few strong thunderstorms
with locally heavy rainfall will be possible especially south of
Highway 82. The cloud cover and rain will hold most sites below
normal in the 80s Tuesday afternoon. Went above gfsmos probability of precipitation Tuesday
and Tuesday night. 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 in the north by sunrise.
Wednesday morning lows are expected to be below normal and in the
lower 60s in the north. Despite the front being south of our County Warning Area
Wednesday will maintain low rain chances across the southern half of
the area. Models still hint at upstream convection in the northwest flow
aloft bringing some activity into our area. An mesoscale convective system Wednesday and
Thursday nights will be possible. Another more potent shortwave will
move over the Southern Plains Thursday and swing across our County Warning Area
Friday. The European model (ecmwf) is stronger with this feature and generates a good
deal more quantitative precipitation forecast across our area than the GFS. Precipitable waters in excess of two
inches is expected to surge north over our area ahead of this
shortwave to support locally heavy rain. Will continue to monitor this
system for flooding potential but rain chances will increase Friday
into Saturday. Warmer and drier conditions look to be in store for
Sunday. /22/


Aviation...VFR conditions will mostly prevail through this evening.
Patchy areas of MVFR category mist could impact sites early this
morning but dissipate shortly after sunrise. Better chances for
isolated afternoon storm will be around kpib/khbg...though any
location along and south of I-20 will have potential. /28/


Preliminary point temps/pops...
Jackson 95 72 93 73 / 6 8 35 40
Meridian 95 70 92 72 / 6 9 40 49
Vicksburg 95 70 94 71 / 6 7 32 40
Hattiesburg 94 73 92 73 / 31 14 43 37
Natchez 92 72 91 72 / 31 8 36 31
Greenville 95 73 93 73 / 3 5 30 59
Greenwood 96 72 93 72 / 4 6 30 59


Jan watches/warnings/advisories...



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