145
FXUS64 KMEG 241700
AFDMEG

Area Forecast Discussion
National Weather Service Memphis TN
1200 PM CDT Fri May 24 2024

...New AVIATION...

.UPDATE...
Issued at 1025 AM CDT Fri May 24 2024

As of 10AM, radar imagery depicts showers and thunderstorms
situated east of the Mississippi River. Severe weather
probabilities at this time remain low due to lack luster lapse
rates across the Mid-South. The greater threat with this activity
is flooding as rainfall rates of 3 inches per hour have been
observed. In addition, several areas have reported flooding of
roadways and streams.

The forecast becomes a bit unclear past midday as 12Z CAMs have
backed off on the redevelopment of storms. However, current
satellite trends depict clearing skies west of the MS River. If
the sun does manage to peek out for a few hours, the environment
will likely recover and additional storm development will be
likely. A more favorable parameter space for severe storms will be
in place this afternoon. Therefore, any storms that do form could
possess damaging winds and large hail. In addition, prolific
rainfall rates will remain and further aggravate rivers and
streams.

Overnight, an additional line of showers and thunderstorms will
dive south across Missouri and Kentucky, eventually impacting the
Mid-South around midnight. Confidence for this round of storms is
higher, but a stout EML at this time should hamper severe storm
development. However, elevated precipitable water values will once
again aid in heavy rainfall within storms.

ANS

&&

.SYNOPSIS...
Issued at 429 AM CDT Fri May 24 2024

Showers and thunderstorms will continue to impact the Midsouth
through the weekend. Some severe storms will be possible,
particularly today and late Sunday. The primary severe weather
threats will be large hail and damaging winds. Otherwise, warm and
humid conditions will prevail.

A few storms will linger across north Mississippi on Monday.
Otherwise, fair weather and lower humidity is forecast early next
week across the Midsouth.

&&

.DISCUSSION...
(Today through Thursday)
Issued at 429 AM CDT Fri May 24 2024

The storm track will continue across the Midsouth through the
weekend, as a belt of strong westerlies extends from the southern
and central Great Plains into the MS River Valley. Under these
strong winds aloft, surface dewpoints in the lower 70s will
contribute to precipitable water values of 1.5 to 2 inches, and
daytime surface-based CAPE nearing 3000 J/kg over the Midsouth.

Thunderstorm timing and coverage will be primarily associated
with midlevel shortwaves, often enhanced by convection over the
southern plains and Ozarks. Similar to early yesterday morning,
KLZK radar shows an area of storms with an apparent MCV lifting
east-northeast across southern AR. Latest CAMs depict this
convection moving through the Midsouth this morning, with isolated
afternoon storms developing in its wake. Confidence in coverage
area is limited by a strong EML. However, should updrafts overcome
the capping nature of the EML, steep midlevel lapse rates (7.0 to
7.5 C/km) will support large hail. With 0-6km bulk shear at or
below 30 knots, surface-based convection should wane with the loss
of surface heating by early evening.

HRRR runs continue to show large run to run variability with
thunderstorm depiction beyond 24 hours. 00Z CAM consensus,
including the HRRR, depicted storms dropping southeast across AR
late this evening, possibly impacting areas around West Helena, AR
and Clarksdale, MS. The 06Z HRRR maintains a robust linear MCS
from central AR to middle TN, with impacts over the entire
Midsouth after midnight. With that said, confidence remains
limited with overnight storm chances and potential impacts. The
convective parameters are at least supportive of large hail and
damaging winds with any storms that develop overnight.

Modest shortwave ridging will limit storm organization potential
Saturday, but not preclude daytime pulse severe. Stronger
westerlies will arrive Sunday afternoon, as the ridge axis lifts
to the Carolinas. Surface based CAPE will reach or exceed
3000 J/kg along and west of the MS River Sunday afternoon. This
strong surface-based instability will likely be capped under a
strong EML south of I-40. This EML will translate east Sunday
evening, as height falls and a weak surface cold front lift
through the Midsouth. Large hail and damaging winds will remain
the primary severe threat Sunday night.

Less humid and slightly cooler air will spread into the Midsouth
early next week, behind Sunday night`s cold frontal passage. A
respite from thunderstorms should last through midweek.

PWB

&&

.AVIATION...
(18Z TAFS)
Issued at 1143 AM CDT Fri May 24 2024

Periods of convection are expected this afternoon and overnight with
a much higher confidence of storms tonight.  Very heavy rainfall
will likely result in brief periods of VFR Vis.  Prevailing wind
will remain from the south to southwest 5-10kts but could be gusty
and variable near thunderstorms. Storms should come to an end
around mid morning with VFR conditions prevailing during the
afternoon hours.

&&

.MEG WATCHES/WARNINGS/ADVISORIES...
AR...Flood Watch through Monday morning for ARZ009-018-026>028-035-
     036-048-049-058.

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

MS...Flood Watch through Monday morning for MSZ001>017-020>024.

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

&&

$$

PUBLIC FORECAST...ANS
AVIATION...JDS