Area Forecast Discussion
Issued by NWS Jackson, MS

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FXUS64 KJAN 280902

Area Forecast Discussion
National Weather Service Jackson MS
402 AM CDT TUE JUN 28 2016

For the Today through Wednesday night period, predawn water vapor
imagery and model analysis showed northwest flow across the CWA
around a subtropical ridge centered over the Southwest US. Latest
predawn surface analysis a 1017 mb ridging over the CWA with a weak
surface boundary. Area radars were not picking up any showers over
the CWA at this time. Predawn temps were in the lower to middle 70s.
Precipitable water was 1.9 to 2.1 inches across the CWA.

The primary concern will be the good convective coverage for today
through this evening in combination with some locally heavy rainfall
potential and a few strong storms. This will be followed by rain
chances decreasing from the north Wednesday into Wednesday night.

For today into tonight we will be looking at precipitable water of
2.0 to 2.25 inches for some locally heavy rainfall. The flow will be
a little better with some areas north of I-20 will have 25-30 knots
of bulk shear from 0-2km to the 0-3km levels. Also a weak front will
push through the area. Low level lapse rates will be around 6-9c.
However with the slightly cooler temps expected highs generally
around 90, expect less instability than on Monday. Also mid level
lapse rates will be weak. Hi-Res models generally keep the stronger
storms south of the CWA for this afternoon into this evening which
seems reasonable. There may be enough dynamics for a few strong
storms with the limited convergence around the frontal boundary with
the primary risk of some gusty winds. So with this in mind will keep
the severe risk out of the HWO.

For Wednesday into Wednesday night we will be looking at a dryer
airmass pushing into the CWA from the north. This will end our rain
chances by Wednesday night. Precipitable water will go below one
inch across the north half on Wednesday night. There may be a little
more instability for convection with highs in the lower 90s. Expect
another day of weak midlevel lapse rates and vertical totals.

As far as temps are concern it will be cool enough to avoid any heat
index concerns through Wednesday afternoon. Highs today will be in
the upper 80s to around 90. Highs on Wednesday will be in the lower
90s. Lows tonight will be from the upper 60s to the lower 70s. Lows
for Wednesday night will be from the middle 60s to the lower 70s/17/

Come Thursday morning the cold front will be south of our CWA. The
ECMWF is a little farther north with the front and tries to generate
some afternoon convection along the front across our southern zones
but model consensus is dry and wl not carry mention of POPs.
Northwest flow aloft will continue Thursday as our CWA remains
between a broad mid level ridge over the southwest CONUS and a mid
level trough over the eastern CONUS. A surface ridge will also be
oriented from the Ohio Valley southwest across the Lower Mississippi
River Valley as well. This will provide a north low level flow over
our region Thursday and help knock dew points into the upper 50s to
lower 60s Thursday afternoon. Thursday night a northern stream
shortwave will drop over the northern plains and swing east across
the Great Lakes region Friday then shift east of the Northeast CONUS
Friday night. This will result in a cold front dropping south over
Tennessee and into northern Mississippi but stalling north of our CWA
by Saturday. The dry weather over our CWA Thursday is expected to
last through Saturday with a couple exceptions. The first exception
is across our southern most zones Friday and Saturday afternoons
where light return flow may help convection along the sea breeze
front edge into our area before dissipating. The second exception is
across our northern most zones Saturday afternoon where convection
along the stalled front may spread south into our area before
dissipating. Little change is expected Sunday but we will have a
moist air mass back over the whole CWA. Daytime heating will lead to
at least a slight chance of afternoon and early evening storms.
Ridging surface and aloft will hold tough over the northern Gulf
Monday and Tuesday while a couple northern stream shortwaves track
across northern Mississippi and help set off storms. Greatest POPs
will be carried over our north each day. /22/


For Today, look for a earlier start to convective activity with the
better coverage across central and southern sections. There will be
brief periods of ceiling and visibility obstructions with the
thunderstorms. There could be some brief heavy downpours and some
gusty winds with the stronger storms. Expect northeast winds at 5-10
knots for today as well as light northeasterly for tonight./17/


Jackson       90  71  92  70 /  59  53  12  12
Meridian      91  72  92  69 /  58  53  16  11
Vicksburg     90  72  92  71 /  56  51  11  10
Hattiesburg   90  73  91  72 /  68  64  30  12
Natchez       88  72  90  71 /  63  59  21  11
Greenville    91  73  92  68 /  31  28   8   7
Greenwood     90  71  92  68 /  37  33   5   8


.JAN Watches/Warnings/Advisories...


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