Tornado Warning 44, NWS Memphis, TN

Area Forecast Discussion
National Weather Service Memphis TN
641 PM CDT Sat Apr 30 2022

.UPDATE...

See 00Z aviation discussion below.

&&

.DISCUSSION... /issued 305 PM CDT Sat Apr 30 2022/

Primary short term forecast concern remains thunderstorms this
evening, a few of which could reach severe limits.

Midafternoon GOES water vapor imagery showed a large closed low
centered over northwest IA. Surface analysis showed a 996mb
occluded low centered the upper low. A cold front extended from
an occlusion triple point near Chicago, southwest through AR and
northeast TX. A colocated low level theta-e and instability axis
extended from the Arklatex into north central AR and south
southeast MO. Despited extensive low to midlevel stratocumulus,
mixed-layer CAPE over north central AR had reached 1500 J/KG at
midafternoon. The presence of the clouds was likely providing
enough convective inhibition to preclude storm development.
Downstream, mostly sunny skies prevailed over over west TN and
north MS, though dewpoints and mixed layer CAPE were considerably
lower, CINH considerably higher. It wasn't until 19Z / 2 PM CDT
that flat cumulus had formed in the Memphis area, with relatively
low dewpoints in the upper 50s.

As we head into early evening, midlevel height falls and eastward
translation of the low level moisture axis will likely drive
convective initiation along and west of the MS River. This will
likely occur where cloud breaks allow can develop. Early evening
instability and modest (around 30 KT) bulk shear will support a
marginal severe hail and damaging wind threat. Post sunset,
waning instability, and lack of a clear surface convergence
feature should result in decreasing intensity and coverage of
storms. This downward convective trend will continue from late
evening through the overnight frontal passage time.

The surface cold front will likely wash out over north MS by
Sunday morning, becoming rather ill-defined under zonal flow
aloft. An amplifying shortwave ridge axis will shift east of the
Midsouth by Monday morning, displaced by diffluent flow ahead of
a ahead of a negatively-tilted upper low in the central plains.
The aforementioned stalled front will race north through the
Midsouth as warm front on Monday, reaching the mid-MS river valley
by afternoon. It appears that a lead shortwave will eject across
the southern plains into the Ozarks Monday morning, driving
thunderstorm development into the Midsouth Monday afternoon.

The remainder of next week appears unsettled, with a progressive
pattern the "wave train" continuing. Difficult to pick a day next
week where rain chances fall below mentionable levels.

PWB

&&

.AVIATION...

00Z TAFs

VFR conditions prevail through the evening. Carried VCSH/VCTS as
the cold front passes later this evening into the early morning
hours. MEM may have a brief period of -TSRA between 02Z and 04Z
as the line passes. Most of the convection looks to be based
around 5000ft, so CIGs shouldn't be too much of an issue for all
sites except TUP which could get down to MVFR conditions in the
post-FROPA morning hours. Winds ahead of the front this evening
will generally be from the S/SE around 10kt, potentially gusting
to up to 18kt. As the front passes, winds slow down to around 5kt
along with a shift to the west. By the end of the TAF period,
looks like winds pick back up to 8-10kt from the northwest.

CAD

&&

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

Hazardous Weather Outlook...UPDATED
National Weather Service Memphis TN
139 PM CDT Sat Apr 30 2022

ARZ009-018-026>028-035-036-048-049-058-MOZ113-115-MSZ001>017-
020>024-TNZ001>004-019>022-048>055-088>092-012045-
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-
139 PM CDT Sat Apr 30 2022

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

.DAY ONE...This Afternoon and Tonight

There is a Slight Risk for severe storms along and west of the
Mississippi River from late afternoon through midevening. Primary
risks include large hail and damaging winds. Secondary threats
include brief tornado and flash flooding.

A Marginal Risk in place to the east for the mid to late evening
hours. During this time, damaging winds and locally heavy rainfall
will be the primary severe weather threats.

.DAYS TWO THROUGH SEVEN...Sunday through Friday

A few strong to severe storms will be possible Monday night.

.SPOTTER INFORMATION STATEMENT...

Spotter activation may be needed this late this afternoon evening.

PWB