585
FXUS64 KHUN 140843
AFDHUN

Area Forecast Discussion
National Weather Service Huntsville AL
343 AM CDT Sun Jul 14 2024

...New NEAR TERM, SHORT TERM, LONG TERM...

.NEAR TERM...
(Today)
Issued at 343 AM CDT Sun Jul 14 2024

Heat will continue to be our primary concern this afternoon into
the early evening hours as high temperatures climb into the upper
90s- with a very low chance (10% or less) of some spots reaching
100 degrees. Heat indices are forecast to reach 98-104 degrees,
nearing our local Heat Advisory criteria of 105 degrees in some
areas. While this will be monitored closely, widespread 105
degree heat indices are not forecast at this time and therefore no
products will be issued with this forecast update. Despite this,
we still encourage everyone to stay hydrated, seek shade or take
breaks during the hottest part of the day, and avoid leaving pets
or people in unattended vehicles.

An MCV moving through MS will be steered by sfc high pressure
located in the southeastern U.S. throughout this morning into the
afternoon, bringing it northeast into the TN Valley. As a result,
low chances (20-30%) of showers were added to the forecast this
afternoon, aided by diurnal heating. Model soundings indicate a
chance for some downburst potential, with higher confidence south
of the Tennessee River. Low level lapse rates are forecast to be
around 9-9.5 C/km coupled with ~1000 J/kg of DCAPE. In addition to
this, storm motion is less than 5 kts and shear continues to be
weak. One caveat within these model soundings is the lack of
moisture-- with PWATs remaining in the 1.3-1.7" range, which is
near or below the median value in SPC sounding climatology per
BMX. Low level RH values are also in the 30-40% range with mid
level RH values remaining under 65% as well. Thus, there is a
potential for these showers to be light rainfall producers with
gusty to damaging winds and a low-medium chance of producing
lightning. We will have to monitor changes in forecast soundings
closely as well as look forward to observed soundings from
surrounding offices within the morning update.

&&

.SHORT TERM...
(Tonight through Thursday)
Issued at 343 AM CDT Sun Jul 14 2024

Dangerous heat is forecast through mid week as highs continue to
climb into the upper 90s in most locations with low chances (10%
or less) of reaching 100 degrees. Monday through Wednesday, heat
indices are forecast to near or exceed Heat Advisory criteria (105
degrees) in portions of northwestern AL (primarily west of I-65).
Therefore, this will have to be closely monitored for potential
product issuance in future updates.

Otherwise, sfc high pressure over the southeastern U.S. will be
maintained through the early part of the week with diurnal heating
allowing low-medium chances (30-40%) of showers/storms. A trough
is forecast to move into the TN Valley, forcing sfc high pressure
eastward and rain chances to increase ahead of the subsequent
front on Wednesday into Thursday. During this time, medium-high
chances of showers/storms (60-80%) will be possible. Sufficient
low level lapse rates as well as instability and high PWATs
(2-2.1", nearing or meeting the 90th percentile per BMX sounding
climatology) will allow any stronger storms that form to be
capable of producing lightning, moderate to heavy rainfall, and
gusty winds.

&&

.LONG TERM...
(Thursday night through Saturday)
Issued at 343 AM CDT Sun Jul 14 2024

Models are hinting at the aforementioned front stalling to our
southeast, continuing to bring rainfall to portions of our area
and some relief from the ongoing drought conditions. Due to this,
at least a low chance of rain was maintained through the long term
period, with higher chances in the afternoon to early evening
hours. The front should provide slight relief from the ongoing
heat, as well. High temperatures during the long term period are
forecast to reach the mid 80s to low 90s with heat indices in the
90s.

&&

.AVIATION...
(06Z TAFS)
Issued at 1155 PM CDT Sat Jul 13 2024

VFR conditions continue through the TAF period at both KMSL and
KHSV. A low chance of fog exists this morning along large bodies
of water, however, confidence is low in this affecting TAF sites.
Therefore, it has been left out of the TAF issuance. Amendments
may be needed if fog forms near the terminals.

&&

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

$$

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