-- Discussion containing changed information from previous version are highlighted. --
680
FXUS64 KHUN 041428
AFDHUN

Area Forecast Discussion
National Weather Service Huntsville AL
928 AM CDT Tue Jun 4 2024

...New NEAR TERM...

.NEAR TERM...
-- Changed Discussion --
(Rest of Today)
Issued at 928 AM CDT Tue Jun 4 2024

The decayed MCS that moved through Mississippi overnight has
continued eastward through the Tennessee Valley this morning-
bringing moderate to heavy rainfall during times and a low chance
of lightning. CAMs are struggling to initialize well with this
system, however, some sort of redevelopment is still forecast
later this afternoon into with diurnal heating contributing to
instability. Therefore, went with blended guidance NBM for PoPs,
keeping medium to high chances (50-70%) for showers with low-
medium chances of lightning this afternoon. With any stronger
storms, gusty winds and small hail may be possible. We are also
outlooked for a marginal/low flash flood risk, meaning at least a
5% risk of rainfall exceeding flash flood guidance within 25 miles
of anywhere within the Tennessee Valley. Rainfall chances
decrease into the evening hours, remaining low (30%). Otherwise,
high temperatures are forecast to reach the low to mid 80s this
afternoon.
-- End Changed Discussion --

&&

.SHORT TERM...
(Tonight through Thursday night)
Issued at 310 AM CDT Tue Jun 4 2024

Coverage of showers and thunderstorms will increase through the
night becoming medium chances (60%) by Wednesday morning. An upper
level low sliding along the U.S and Canadian border will hit a
blocking pattern as it reaches just NW of the Great Lakes. The
associated sfc low will have a cold front draped through the
Midwest and back into the ArkLaTex region. Another shortwave will
traverse through the region to help provide prefrontal convection
on Wednesday. Greatest coverage of showers and storms are expected
Wednesday afternoon when high chances (80%) are anticipated.
Forecast soundings continue to show PWATS reaching 1.7-1.9"
(75th-99th percentile) and SBCAPE values 2k J/kg or higher. The
rounds of convection will be capable of producing gusty winds and
heavy rainfall. With little deep layer shear, not expecting
stronger storms at this time, however will be monitoring for any
hydro concerns.

The front itself does not push through until Thursday and it will
taper off precip chances throughout the day. The drier air behind
the front will provide a decrease in cloud cover and no precip by
Thursday night.

The rounds of rainfall and cloudy conditions on Wednesday will
place daytime highs in the mid 80s with lows in the upper 60s.
Highs will be slightly warmer on THursday in the upper 80s and
lows in the low/mid 60s.

&&

.LONG TERM...
(Friday through Monday)
Issued at 310 AM CDT Tue Jun 4 2024

Will remain under the influence of northwesterly flow aloft for the
long term period, as Friday still looks dry in the wake of a cold
front. High pressure will build to our northwest during the day, and
afternoon highs will be on the "cool" side topping out in the low
80s. Trends have favored dry weather lasting through Saturday, as the
first of a series of weaker shortwave disturbances has slowed down,
remaining west of the area until Sunday morning. Temperatures will be
similar on Saturday, topping out in the low 80s as clouds begin to
gradually increase from the west into the evening hours. The
aforementioned shortwave will help bring better moisture to the area,
but will likely remain rain free until Sunday when a stronger
trough digs into the Midwest, and rich Gulf moisture increases ahead
of a cold front. Models diverge a bit at this range, but right now it
looks like we will see at least low chances (20-30%) for rain and
storms Sunday through Monday, though questions remain on if this will
be one round or multiple depending on the evolution of the trough and
associated front. Highs will remain near the mid 80s through Monday
with lows in the 60s each night.

&&

.AVIATION...
(12Z TAFS)
Issued at 625 AM CDT Tue Jun 4 2024

Low confidence forecast for this TAF package as showers/storms
have not materialized upstream as anticipated. A few VCSH have
popped up this morning and now anticipating isolated coverage
throughout this morning and into this afternoon. Greater coverage
of showers and storms should slide in ~04/05Z and bring MVFR
conditions til the end of the TAF period.

&&

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

$$

NEAR TERM...HC
SHORT TERM....JMS
LONG TERM....25
AVIATION...JMS