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FXUS64 KHUN 161050
AFDHUN

Area Forecast Discussion
National Weather Service Huntsville AL
550 AM CDT Tue Jul 16 2024

...New AVIATION...

.NEAR TERM...
(Today)
Issued at 405 AM CDT Tue Jul 16 2024

A low chance (20% or less) of showers has been added to the
forecast this morning south of the TN River to accommodate the
ongoing convection in portions of Cullman county and south of our
County Warning Area. This convection is a result of a weak
convergence boundary along the western edge of the Bermuda High
and slightly stronger SW winds westward along the Mississippi
Valley with enough instability present to allow some lightning
development as well as moderate to heavy rainfall. These storms
are forecast to weaken into the morning hours with little sfc CAPE
and weak low level lapse rates to support the ongoing convective
development.

Otherwise, a low chance (20-30%) of patchy fog is possible this
morning throughout the TN Valley- especially in areas that
received rainfall Monday and along large bodies of water. Any fog
that forms is forecast to dissipate shortly after sunrise. Low-
medium chances of showers/storms (20-40%) are forecast to return
to the area this afternoon with diurnal heating, bringing risks of
frequent lightning, moderate to heavy rainfall, and gusty winds.

Despite rain chances and cloud cover, heat will be a large concern
today throughout the TN Valley. High temperatures are forecast to
reach the mid to upper 90s with heat indices in the 99-106 range.
A Heat Advisory is in effect beginning at 10 AM and continuing
through 8 PM CDT for counties along and westward of I-65. We
encourage everyone to stay hydrated, avoid being outdoors during
the afternoon hours if possible, and never leave pets or people in
vehicles.

&&

.SHORT TERM...
(Tonight through Friday)
Issued at 405 AM CDT Tue Jul 16 2024

Tonight, low temperatures drop into the low to mid 70s. Both MSL
and HSV are forecast to drop to the mid 70s which could be close
to breaking their record for high minimum temperatures for July
17th. HSV`s record is 77 degrees (set in 1932) while MSL`s record
is 78 degrees (set in 1980). Therefore, it is safe to say these
temperatures are above-normal.

Dry weather is forecast overnight before high rain chances
(70-80%) return Wednesday and continue through Thursday as a cold
front approaches the Tennessee Valley from the northwest. Low-
medium chances of showers/storms (30-60%) continue into Friday.
During this time, several rounds of showers are forecast to bring
a potential for moderate to heavy rainfall, frequent lightning,
and gusty winds. PWATs are forecast to be in the 1.7-1.9 range in
HREF solutions, nearing the 90th percentile per BMX sounding
climatology. Therefore, a low flooding threat is a concern as
these continue both throughout the daytime as well as overnight.
The Weather Prediction Center (WPC) has placed portions of our
area in a Marginal (threat level 1/4) Excessive Rainfall Outlook
Wednesday morning through Thursday morning, meaning there is at
least a 5% risk of rainfall exceeding flash flood guidance.

The forecast rainfall and surplus of cloud cover will allow
temperatures to cool off for the remainder of the work week,
capping high temperatures in the 80s Thursday and Friday. On
Wednesday, high temperatures in the 90s are still forecast with
heat indices in the 99-104 range, however, we will be monitoring
how early rainfall develops which may mitigate the need for any
Heat Products as temperatures would be cooler than currently
forecast. Be sure to check back in for the latest forecast
information.

&&

.LONG TERM...
(Friday night through Monday)
Issued at 405 AM CDT Tue Jul 16 2024

Medium-high shower/storm chances continue through the weekend as
the aforementioned front is forecast to stall to our southeast,
allowing higher rain chances in our southeastern counties
(Cullman, Marshall, Dekalb, Jackson) Friday before lifting back
northward due to high pressure off the east coast of Florida. High
temperatures in the 80s continue during this time and the need for
any Heat Products is not expected.

&&

.AVIATION...
(12Z TAFS)
Issued at 550 AM CDT Tue Jul 16 2024

VFR conditions continue through the TAF period at both KMSL and
KHSV, however, a PROB30 group exists this afternoon at KHSV for
potential MVFR conditions due to lowered visibilities as a result
of showers. There is a low chance (20% or less) of showers
impacting KMSL this afternoon, however, confidence is too low to
include any mention in the official TAF package. Therefore,
amendments may be needed.

&&

.HUN WATCHES/WARNINGS/ADVISORIES...
AL...Heat Advisory from 10 AM this morning to 8 PM CDT this evening
     for ALZ001>007-016.

TN...Heat Advisory from 10 AM this morning to 8 PM CDT this evening
     for TNZ096.

&&

$$

NEAR TERM...HC
SHORT TERM....HC
LONG TERM....HC
AVIATION...HC