343
FXUS64 KMEG 270825
AFDMEG

Area Forecast Discussion
National Weather Service Memphis TN
325 AM CDT Fri Sep 27 2024

...New SYNOPSIS, DISCUSSION...

.SYNOPSIS...
Issued at 325 AM CDT Fri Sep 27 2024

Rain and gusty winds are expected through Saturday as the remnants
of Helene spin down over Kentucky. Rainfall totals of 3 to 6
inches are expected across West Tennessee, eastern Arkansas, and
the Missouri Bootheel with lesser amounts across north
Mississippi. Weather will calm down Sunday into early next week
with temperatures warming into the lower to mid 80s by Tuesday. A
cold front will pass through Tuesday night, knocking temperatures
back into the 70s during the middle and end of next week.

&&

.DISCUSSION...
(Today through Thursday)
Issued at 325 AM CDT Fri Sep 27 2024

Helene made landfall in the Florida Big Bend area a few hours ago
and is racing northward across GA this morning. Rain bands are
steadily pushing west across the Mid-South this morning. Surface
winds are beginning to increase across the Bootheel and NE AR.

Helene`s surface circulation will scream north to KY by 1 pm this
afternoon and then hang out and spin down over the next couple of
days. Meanwhile the upper level system associated with Helene
will merge with the upper low over the Mid-South and by late today
the entire system will become vertically stacked over KY.
Tropical moisture will rotate into the Mid-South over the next
24-30 hrs as PWs climb to around 2 inches. This moisture combined
with strong upward motion in the upper low`s deformation zone will
result in extended period of moderate to heavy rain with banding
across the northern half of the Mid-South through this evening.
Rainfall totals of 3 to 6 inches is likely along and north of the
TN/MS line. A Flood Watch continues through 7 am Saturday. As the
system slowly fills the upward motion fields weaken and rain
intensity starts to diminish overnight.

Strong wind fields associated with Helene will begin to rotate
into the area this morning continuing into tonight as 850 mb
winds increase to around 50 kts across northern parts of the area.
The latest hi-res guidance indicates that gusts around 40 mph are
possible mainly north of I-40 and especially over the Missouri
Bootheel and NE AR. The NBM puts the probability of 40 mph+ gusts
at over 75% across the Bootheel and NE AR. A Wind Advisory is in
effect roughly north of I-40 from 7 am this morning to 7 am
Saturday.

Showers will continue on Saturday and Sunday as the system
continue to spin down over SW KY though QPF amounts will be much
lighter. Breezy conds will linger on Saturday with much lighter
winds by Sunday. The remnants of Helene eventually get pushed
east by a trough moving into the Upper Great Lakes early next
week. Dry weather will return and temps will climb into the upper
70s and lower 80s Monday and the lower to mid 80s by Tuesday. A
cold front will push through the area Tuesday night. The front
looks moisture starved attm and should pass through dry. Cool
high pressure will build in for the end of the week with pleasant
temps and a less humid airmass. Expect lots of lows in the 50s to
from Wednesday into Friday.

&&

.AVIATION...
(06Z TAFS)
Issued at 1148 PM CDT Thu Sep 26 2024

VFR conditions are expected to begin deteriorating to MVFR
conditions overnight, dropping to IFR conditions towards sunrise,
and persisting through the remainder of the 06Z TAF period.
Scattered showers will retrograde W/SW over the next few hours
with rain becoming more widespread as tropical moisture from
Hurricane Helene spreads further inland. Confidence remains low
with the potential for any thunderstorms to affect TAF sites
through the period with instability remaining limited at best.
Winds are expected to remain elevated with occasional wind gusts
at all sites, especially MKL and JBR.

&&

.MEG WATCHES/WARNINGS/ADVISORIES...
AR...Flood Watch through Saturday morning for ARZ009-018-026>028-035-
     036-048-049.

     Wind Advisory from 7 AM this morning to 7 AM CDT Saturday for
     ARZ009-018-026>028.

MO...Flood Watch through Saturday morning for MOZ113-115.

     Wind Advisory from 7 AM this morning to 7 AM CDT Saturday for
     MOZ113-115.

MS...Flood Watch through Saturday morning for MSZ001>009.

TN...Flood Watch through Saturday morning for TNZ001>004-019>022-
     048>055-088>092.

     Wind Advisory from 7 AM this morning to 7 AM CDT Saturday for
     TNZ001>004-019>022-048>051.

&&

$$

PUBLIC FORECAST...SJM
AVIATION...CJC