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Area forecast discussion 
National Weather Service Memphis Tennessee
921 am CDT Friday Oct 31 2014

Update...
updated for sky cover and high temperatures.

&&

Discussion...

Latest visibile satellite indicating mostly clear skies across
western and southern portions of the midsouth this morning...with
a band of Post frontal stratocumulus approaching the area from
southern Missouri. Have reduced sky cover through the morning
hours and increased the cloud amounts for this afternoon area wide.
From this...temperatures have been a bit warmer as of 9 am and
will continue to climb a few more degrees through about noon
before becoming steady or slowly falling with the aniticpated cold air advection.
The remainder of the forecast this morning is on track.

Jab

&&

Previous discussion... /issued 712 am CDT Friday Oct 31 2014/

Discussion... /issued 351 am CDT Friday Oct 31 2014/

Early season Arctic cold frontal passage remains the primary
forecast concern. 08z/3 am CDT surface map showed this front near
a Kansas City to Chicago line. A 1038mb surface pressure ridge was
located over the eastern Dakotas...were temperatures prevailed in the
teens.

Unlike most early season freeze events in the midsouth...in which
calm winds and radiational cooling dominate...tonight will see a
mixed boundary layer and cold advection. As such... expect less of
a terrain or urban heat island temperature influence...and less
temperature sensitivity to cloud cover. With 925mb temperatures prognosticated
by the NAM to range between minus 1c an minus 3c... have upgraded
tonight/S freeze watch to a freeze warning areawide. If winds stay
up as expected...wind chills should range from the lower to middle 20s
near sunrise Saturday morning.

The center of the Arctic high will settle over the Ohio an Tennessee
valleys Saturday night...leading to light or calm winds over the
midsouth. Under clear skies.. the dry airmass will likely cool to
below freezing away from the Memphis urban heat island. With the
growing season ended...freeze headlines are typically suspended for
the season following the first occurrence. However...have opted to
continue the freeze headlines /freeze watch/ for Saturday night...
given that it is part of the same event. Seasonal suspension of
freeze headlines can then be evaluated following this weekend/S
event.

The early part of next week will see southerly return flow develop
around the retreating Arctic high...accompanied by building
midlevel heights. Mild temperatures and warmer dewpoints will prevail
ahead of a slowly approaching midweek Pacific cold frontal
passage. This front will serve as a focus for scattered to perhaps
numerous showers and a few thunderstorms Tuesday night and
Wednesday...before it washes out under weakening flow aloft.

Forecast confidence suffers a bit for the late next week... as the
GFS and European model (ecmwf) models diverge with their respective handling of a
cut off upper low over the southern rockies or Southern Plains.

Pwb

&&

Aviation...

12z taf set

Morning fog at kmkl should lift shortly. Meanwhile expect a band
of clouds with ceilings between 3500-5000ft to move through the
midsouth today along a cold front. Can/T rule out ceilings briefly
dropping to MVFR at kmkl with isolated rain showers. For now will keep
VFR and just mention vcsh. Winds will become strong from the north-northwest
around 15 kts sustained with gusts between 20-28 kts between
14-18z. Speeds will diminish between 23-04z. Overnight...expect northwest
winds of 6-10 kts.

Krm

&&

Meg watches/warnings/advisories...
Arkansas...freeze watch from late Saturday night through Sunday morning for
Clay-Craighead-Crittenden-cross-Greene-Lawrence-Lee Arkansas-
Mississippi-Phillips-Poinsett-Randolph-St. Francis.

Freeze warning from midnight tonight to 9 am CDT Saturday for
Clay-Craighead-Crittenden-cross-Greene-Lawrence-Lee Arkansas-
Mississippi-Phillips-Poinsett-Randolph-St. Francis.

MO...freeze watch from late Saturday night through Sunday morning for
Dunklin-Pemiscot.

Freeze warning from midnight tonight to 9 am CDT Saturday for
Dunklin-Pemiscot.

MS...freeze watch from late Saturday night through Sunday morning for
Alcorn-Benton MS-Calhoun-Chickasaw-Coahoma-DeSoto-Itawamba-
Lafayette-Lee MS-Marshall-Monroe-Panola-Pontotoc-Prentiss-
Quitman-Tallahatchie-Tate-Tippah-Tishomingo-Tunica-Union-
Yalobusha.

Freeze warning from midnight tonight to 9 am CDT Saturday for
Alcorn-Benton MS-Calhoun-Chickasaw-Coahoma-DeSoto-Itawamba-
Lafayette-Lee MS-Marshall-Monroe-Panola-Pontotoc-Prentiss-
Quitman-Tallahatchie-Tate-Tippah-Tishomingo-Tunica-Union-
Yalobusha.

Tennessee...freeze watch from late Saturday night through Sunday morning for
Benton Tennessee-Carroll-Chester-Crockett-Decatur-Dyer-Fayette-
Gibson-Hardeman-Hardin-Haywood-Henderson-Henry-Lake-
Lauderdale-Madison-McNairy-Obion-Shelby-Tipton-Weakley.

Freeze warning from midnight tonight to 9 am CDT Saturday for
Benton Tennessee-Carroll-Chester-Crockett-Decatur-Dyer-Fayette-
Gibson-Hardeman-Hardin-Haywood-Henderson-Henry-Lake-
Lauderdale-Madison-McNairy-Obion-Shelby-Tipton-Weakley.

&&

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