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Area forecast discussion 
National Weather Service Jackson MS
346 am CDT Thursday Jul 28 2016

Discussion...
short term (today through Friday night)...continued higher rain
chances is once again the headline of today's forecast, particularly
over the northern half of the area. The shortwave/mesolow that
instigated much of wednesday's activity is now lifting into the Ohio
Valley, but mid-level troughing will linger over the lower MS valley
today. There also remains a plume of notably high atmospheric
moisture extending from East Texas through the Tennessee Valley, encompassing
all of the County Warning Area except for the Pine belt. In fact, our 00z sounding
from last night sampled a 2.1" precipitable water. A low level jet streak will also
be present through this corridor today. Given this setup, showers are
expected to develop early in the day, likely across the Delta,
spreading across other portions of the area and becoming more
numerous through midday. A limited threat for flash flooding
continues over mainly the north/west portion of the area into today,
given the plethoric deep layer moisture. Forecast daytime highs were
cut down toward raw model guidance due to the anticipation of
clouds/precip interrupting insolation. The exception to all of this
is across the Pine belt, where convection is expected to be more
isolated, thus allowing temps to remain closer to normal.

A decrease in coverage is expected this evening due to both to
atmospheric overturning and the loss of daytime heating. Weak
mid/upper troughing will persist into Friday, but guidance suggests
the deep layer moisture plume will become a bit less fearsome.
Still, rain chances will remain above normal across the area, with
global models hinting at activity beginning early in the day again.
With somewhat less coverage anticipated, daytime temps aren't
expected to be impacted quite as significantly as today over most of
the area. /Dl/

Long term (saturday through thursday)...unsettled weather will
continue through the long term. An upper trough/sfc front will remain
north of the area through the first half of the period. This,
combined with plentiful moisture(as characterized by 2-2.2 inch precipitable water
values), will bring chance to likely pops through much of the period.
By Monday, the upper trough will lift off to the northeast and upper
ridging will build in a little from the west. The arklamiss will
remain on the eastern side of this ridge, which will allow for
continued higher chances for rain in our soupy airmass.

Temperatures will be roughly around or a few degrees above normal
through the period, with the temperatures getting warmer toward the
end of the week. With dewpoints in the lower to mid 70s, heat
indices will be in the 100 to 105 range through much of the period,
resulting in some elevated heat stress issues. /28/

&&

Aviation...IFR/MVFR ceilings from low stratus cover much of the
northern half of the area this morning, and may linger well into the
day as scattered rain showers/thunderstorms and rain are expected to develop across this region
through the morning hours. Precip is expected to be more isolated to
scattered farther south in the area. Outside of the rain, VFR
conditions should prevail across the area by afternoon, continuing
into this evening. /Dl/

&&

Preliminary point temps/pops...
Jackson 88 73 92 74 / 68 30 41 24
Meridian 92 74 94 74 / 48 29 44 26
Vicksburg 87 73 92 75 / 85 31 39 18
Hattiesburg 92 74 93 75 / 26 25 40 21
Natchez 88 72 92 73 / 59 27 31 17
Greenville 84 72 91 74 / 72 32 40 20
Greenwood 82 70 89 73 / 67 33 42 23

&&

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

$$

Dl/28

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