367
FXUS64 KHUN 061336
AFDHUN

Area Forecast Discussion
National Weather Service Huntsville AL
836 AM CDT Mon May 6 2024

...New NEAR TERM...

.NEAR TERM...
(Rest of Today)
Issued at 836 AM CDT Mon May 6 2024

Small MCS cluster has shifted into the Chattanooga area, with
lingering light rain dissipating rapidly in southern middle TN and
northeast AL. Cluster of TSRA in north MS and southwest TN
continues to develop, but propagation eastward has been thwarted
by subsidence behind the departing shortwave and stability in the
wake of previous convection. Thus, confidence in redevelopment for
our area today is lowering with time. CAMS guidance suggests this
as well. However, will maintain a low PoP just in case for now as
we further assess the environment that develops with daytime
heating.

&&

.SHORT TERM...
(Tonight through Wednesday night)
Issued at 443 AM CDT Mon May 6 2024

The remnants of afternoon showers and thunderstorms today should
spread east-northeastward and out of the local area shortly after
sunset this evening, and although there is a low probability for
redevelopment of a few showers after Midnight as low-level SSW
flow strengthens ahead of a dryline and broken QLCS surging
eastward into the Mid/Upper-MS Valley, we will leave the forecast
dry at this time. Otherwise, it will be a very warm night, with
lows in the upper 60s for much of the region due to elevated SSW
winds and development of low stratus clouds prior to sunrise.

Latest solutions from the 00Z CAMs suggest that a subtle surface
trough ahead of the Pacific cold front/dryline to our north may
initiate the development of thunderstorms to our southwest (across
the Arklamiss region) late Tuesday morning that would spread
northeastward into our forecast area during the afternoon, with
additional storms likely to develop along the same trough across
our region as morning low clouds disperse allowing for rapid
destabilization early Tuesday afternoon. With mid-level flow
predicted to back to W or WSW and increase to 35-45 knots in the
wake of a departing shortwave ridge, resultant deep-layer shear
will support multicell clusters and perhaps a few supercells that
could produce large hail/damaging winds (especially as steepening
lapse rates aloft and surface temps in the mid 80s will generate
moderate-strong instability highlighted by CAPE in the 2000-3000
J/kg range). This regime may persist into Tuesday evening, with
separate clusters of storms (originating along a frontal
confluence axis across the OH Valley) perhaps propagating
southeastward into our region after Midnight in the presence of a
WSW low-level jet of 25-35 knots. With shear and instability
remaining favorable for strong-severe storms throughout the
overnight hours, a Marginal (Level 2/5) Risk is warranted.

During the day on Wednesday, it still appears as if a frontal
wave (originating across the southern High Plains Tuesday) will
shift northeastward from the OK-KS border into the Mid-MS Valley.
Rapid development of intense convection is expected to occur
Wednesday afternoon within a very unstable and strongly sheared
environment to our northwest (in the vicinity of the cyclone`s
trailing cold front from southern MO into northeastern TX).
Although there are still some minor differences in timing, this
activity should evolve into a potent MCS Wednesday evening as it
spreads southeastward, reaching the local CWFA in the 6-12Z
timeframe Thursday. Environmental parameters appear quite
favorable for a high impact severe thunderstorm event for our
region during this timeframe, primarily from the standpoint of
large hail and damaging wind. However, if the low-level jet
strengthens to 30-40 knots (as indicated by some guidance), then
the risk for a few tornadoes will increase as well.

&&

.LONG TERM...
(Thursday through Sunday)
Issued at 443 AM CDT Mon May 6 2024

Trailing stratiform precipitation in the wake of a rather broad
MCS early Thursday morning will likely be in progress across much
of the region at 12Z Thursday, but should slowly spread
southeastward over the course of the morning. Additional showers
and perhaps a few storms may also redevelop during the afternoon
as a cold front shifts southeastward through the TN Valley, but
airmass recovery in the wake of widespread early morning precip
should not be sufficient to raise concern for strong-severe
convection. A final round of postfrontal showers may occur late
Thursday night, along the northern fringe of another well
organized convective complex traveling eastward along the central
Gulf Coast. Beyond this point, a cooler/drier airmass in the wake
of the cold front will reduce POPs to around 10% on Friday and
Saturday. However, there are indications that another Gulf low may
develop late in the weekend, with a slight chance POP for showers
introduced on Sunday. Highs this weekend will be in the lower
70s, with lows in the l-m 50s.

&&

.AVIATION...
(12Z TAFS)
Issued at 648 AM CDT Mon May 6 2024

Showers and thunderstorms associated with a northward-moving warm
front will continue to impact the HSV/MSL terminals thru late
this morning, with TEMPO groups for MVFR conds included btwn
12-16Z (which is also the timeframe when additional AWWs for
lightning appear most likely). Beyond this point, the coverage of
convection should diminish this aftn and become focused north of
the TN River, so we will not mention additional SHRA/TSRA in the
forecast at this point. Forecast soundings indicate that skies
will begin to clear around sunset, but potential development of
BR/FG will be hindered by a persistent SSW wind of 5-10 kts. Low
stratus clouds may develop across the region btwn 10-12Z Tuesday,
providing MVFR cigs once again.

&&

.HUN WATCHES/WARNINGS/ADVISORIES...
AL...None.
TN...None.
&&

$$

NEAR TERM...17
SHORT TERM....70
LONG TERM....70
AVIATION...70