Flash Flood Warning 62, NWS Memphis, TN

Area Forecast Discussion
National Weather Service Memphis TN
808 PM CDT Wed Sep 26 2018

.UPDATE...
A broad upper-level trough is moving across the central CONUS this
evening with deep southwesterly flow aloft. A southwest to
northeast oriented jet streak was situated from the Mid-
Mississippi Valley through the great Lakes, with the Mid-South
located in the front entrance region. Instability, even elevated,
is pretty limited in the post frontal air mass but deep moisture
has kept precipitable water values generally in the 1.5 to 2.0
inch range.

Large scale ascent attendant to the approaching trough will
enhance the mesoscale lift associated with the jet streak to
produce showers, and perhaps and isolated thunderstorm, across the
Mid-South overnight. PoPs were expanded area wide and increased
into chance category (or higher). While average rainfall amounts
will not be as significant as in previous days, there remains a
potential for localized heavy rainfall, especially across
northeast MS where instability is a bit more robust. Only minor
changes were included to the remainder of the forecast.

Johnson

&&

.PREV DISCUSSION... /issued 342 PM CDT Wed Sep 26 2018/

DISCUSSION...

Midafternoon GOES water vapor imagery showed a longwave trof over
the western U.S., centered over the Rocky Mountains. Downstream
of this feature, southwest flow extended into the Midsouth from
the Texas coast. An upper jet core and baroclinic leave was
evident lifting into the Ozarks, ahead of a trof over the southern
plains.

At the surface, a cold front extended from near Tupelo to
Greenwood, MS. This front had slowed its southward progress and
wasn't particularly well-defined but was providing sufficient
convergence for a few thunderstorms near and southwest of Tupelo.
Brief heavy showers and storms will be possible along the front
through late afternoon, but with the main elevated warm conveyor
belt shifted well to the east, flash flooding threat should be
minimal into early evening.

Cooler temps will be main story on Thursday, despite some breaks
in the clouds behind and exiting midlevel trof. By Saturday,
northwesterly flow aloft transitions to westerly. As the upper
pattern deamplifies, a rather strong cold front will likely stall
to our north, extending from northern OK into the Ohio River
valley. With no change of airmass, expect Midsouth temps and
humidity levels to gradually return to near normal by Saturday.

An upper level subtropical height ridge will begin building north
from the northern gulf and FL into the southeast states on Sunday,
and directly over the Midsouth by Midweek. This will bring well
above normal daytime temps and only limited chances of daytime
thunderstorms.

PWB

&&

.AVIATION...

00Z TAF Set

IFR/MVFR CIGS will plague KMEM, KMKL, and KTUP over much of the
next 24 hours as a surface low pressure center moves northeastward
along a stalled front that is currently located across NE
Mississippi. Showers will develop in association with the low as
well as an upper trof that is moving through the area. Models do
show some elevated instability thus can't rule out a thunderstorm
occurring but for now have left mention out of TAFs at KMEM and
KMKL. Do expect some thunderstorm development near KTUP during the
afternoon hours tomorrow along the front thus have added mention
of VCTS. Overall winds will be from the NW-NE at 5-10 mph.

KRM

&&

.MEG WATCHES/WARNINGS/ADVISORIES...
AR...None.
MO...None.
MS...None.
TN...None.

&&

Hazardous Weather Outlook...UPDATED
National Weather Service Memphis TN
1024 AM CDT Wed Sep 26 2018

ARZ008-009-017-018-026>028-035-036-048-049-058-MOZ113-115-
MSZ001>017-020>024-TNZ001>004-019>022-048>055-088>092-271730-
Alcorn-Benton MS-Benton TN-Calhoun-Carroll-Chester-Chickasaw-Clay-
Coahoma-Craighead-Crittenden-Crockett-Cross-DeSoto-Decatur-
Dunklin-Dyer-Fayette-Gibson-Greene-Hardeman-Hardin-Haywood-
Henderson-Henry-Itawamba-Lafayette-Lake-Lauderdale-Lawrence-
Lee AR-Lee MS-Madison-Marshall-McNairy-Mississippi-Monroe-Obion-
Panola-Pemiscot-Phillips-Poinsett-Pontotoc-Prentiss-Quitman-
Randolph-Shelby-St. Francis-Tallahatchie-Tate-Tippah-Tipton-
Tishomingo-Tunica-Union-Weakley-Yalobusha-
1024 AM CDT Wed Sep 26 2018

This hazardous weather outlook is for portions of East Arkansas...
the Missouri Bootheel...North Mississippi...and West Tennessee.

.DAY ONE...Today and Tonight

Residual areal flooding will occur through this afternoon over
portions of northeast Mississippi near and to the southeast of New
Albany. This flooding is a result of heavy rainfall from earlier
this morning.

.DAYS TWO THROUGH SEVEN...Thursday through Tuesday

The threat for widespread hazardous weather is low.

.SPOTTER INFORMATION STATEMENT...

Spotter activation is not anticipated at this time.

PWB