Flash Flooding and Heavy Rain in Mississippi, June 8 to 10, 2021

Area Forecast Discussion...UPDATED
National Weather Service Memphis TN
700 AM CDT Tue Jun 8 2021

.UPDATE...
Updated for 12Z Aviation Forecast Discussion below.

&&

.PREV DISCUSSION... /issued 457 AM CDT Tue Jun 8 2021/

DISCUSSION...

A decently busy night across the Mid-South at this hour. Latest
KNQA radar sweep shows two distinct areas of precipitation. The
first area is finally lifting out of northeast Mississippi, while
the latter is moving into the Mississippi Delta region. Portions
of north Mississippi received up to four inches of rainfall
overnight. Rainfall rates have been extremely efficient, even
without the presence of high reflectivity on radar. Current dual-
pol rainfall rates are in the 2 to 3 inch per hour range and do
not show signs of weakening. All CAMs are in good agreement
through late morning on the evolution of an MCV slowly rotating
into our area from the southwest. This will result in training of
showers and thunderstorms across much of north Mississippi. Went
ahead and issued a Flash Flood Watch for areas with highest
confidence, but do feel that it could be expanded to include the
rest of north Mississippi if trends continue into the afternoon
hours.

The aforementioned MCV is expected to rotate through much of the
Mid-South through late afternoon. With PWAT values near 2 inches
and the potential for developing cold pools, heavy rainfall and
gusty winds look to be the main threats at this time. Will
continue to advertise both in the HWO.

The upper level low that has remain parked over the Mid-South for
the past several days, will continue to be the main influence of
our weather through at least Friday. This largely translates to
periods of showers and thunderstorms each day and night. The NBM
continues to churn out very high POPs, but still feel that it is
overdoing it. Capped POPs around 60 percent, as coverage will
likely remain scattered at times and rather unpredictable.
Nonetheless, heavy cloud cover and rain will continue to keep
temperatures several degrees below normal. Expect highs around 80
each day with lows around 70.

The upper low will finally open into a wave and slowly migrate
east on Friday. This should result in a short period of dry
weather as upper level ridging builds into the region. However,
upper level flow looks to remain northwest, as another wave drops
down across the Mississippi Valley. This may put us in a MCS
pattern with continued chances for showers and thunderstorms each
day through the weekend. Long term models suggest that the ridge
over the Four Corners Region may expand east and build in across
the Mid-South. This solution could turn off the rainfall faucet
for a few days early next week. Stay tuned.

AC3

&&

.AVIATION...
12Z TAFs

Slow-moving meso vortex/compact upper low over AR will interact
with a tropical maritime airmass for scattered to numerous
SRHA. TSRA likely most numerous to the south and east of MEM this
morning, with some additional TS expansion over the remainder of
the Midsouth during the heat of the afternoon. Added a LLWS
mention at MEM, with NAM progged 50KT SSW winds at FL020 this
evening. Otherwise, IFR potential will gradually increase
areawide overnight.

PWB

&&

.MEG WATCHES/WARNINGS/ADVISORIES...
AR...Flash Flood Watch through this evening for Lee AR-Phillips.

MO...None.
MS...Flash Flood Watch through this evening for Coahoma-DeSoto-Panola-
     Quitman-Tallahatchie-Tate-Tunica.

TN...None.
&&

Hazardous Weather Outlook...CORRECTED
National Weather Service Memphis TN
512 AM CDT Tue Jun 8 2021

ARZ009-018-026>028-035-036-048-049-058-MOZ113-115-MSZ001>017-
020>024-TNZ001>004-019>022-048>055-088>092-091215-
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-Lee AR-Lee MS-
Madison-Marshall-McNairy-Mississippi-Monroe-Obion-Panola-Pemiscot-
Phillips-Poinsett-Pontotoc-Prentiss-Quitman-Shelby-St. Francis-
Tallahatchie-Tate-Tippah-Tipton-Tishomingo-Tunica-Union-Weakley-
Yalobusha-
512 AM CDT Tue Jun 8 2021

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

.DAY ONE...Today and Tonight

There is a moderate risk of excessive rainfall across northwest
Mississippi and southeast Arkansas, with a slight risk across the
rest of the Mid-South. Very efficient rainfall and training of
showers and storms could result in localized flash flooding. A
Flash Flood Watch is in effect for portions of northwest
Mississippi and southeast Arkansas through this evening.

There is a Marginal Risk of severe thunderstorms across the
majority of the Mid-South this afternoon. Damaging winds and
heavy rainfall are the main threats.

Please refer to our webpage for the latest hazards.

.DAYS TWO THROUGH SEVEN...Wednesday through Monday

Showers and thunderstorms are expected each afternoon and evening
through at least Thursday. These showers and storms could produce
locally heavy rainfall and gusty winds.

.SPOTTER INFORMATION STATEMENT...

Spotter activation is not anticipated at this time.

AC3

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE MEMPHIS TN
920 AM CDT TUE JUN 08 2021

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0915 AM     FLASH FLOOD      2 WNW BATESVILLE        34.33N  89.97W
06/08/2021                   PANOLA             MS   EMERGENCY MNGR

            PART OF OLD PANOLA ROAD IS WASHED OUT NEAR THE BRIDGE
            OVER THE TALLAHATCHIE RIVER.

&&

MJ