129
FXUS64 KHUN 240338
AFDHUN

Area Forecast Discussion
National Weather Service Huntsville AL
1038 PM CDT Sun Jun 23 2024

...New AVIATION...

.NEAR TERM...
(Rest of tonight)
Issued at 950 PM CDT Sun Jun 23 2024

Scattered showers and thunderstorms in Tennessee/Kentucky
continue to develop and move SE along a couple of pre-frontal
trough axes ahead of a primary cold front further north. This cold
front appears to extend from northeastern Kentucky into northern
Arkansas.

Very moist air ahead of this front can be seen in observations
with dewpoints in the lower 70s to around 80 degrees in a few
spots. This is helping to keep a good amount of elevated and
surface based CAPE in place this evening (1000-2000 J/KG) near and
ahead of this front. Models seem to be a bit light on 0-8 km
shear (15 to 20 kts versus 30-40 kts). Luckily mid level lapse
rates are not very strong. Low level lapse rates are still decent
(6.0 to 6.5 degrees/km), but not great. All this being said,
strong storms look like a good possibility as this front pushes
through tonight into the early morning hours. We could see a
severe storm, likely mainly in southern middle Tennessee. Good
DCAPE values near and ahead of the front can be seen in meso-
analysis. Thus, the main threat with any severe storm would be
strong to damaging winds.

It will be a very warm night, based on several models actual
movement of the main cold front southward. Many models show this
front only moving into southern middle Tennessee by 7 AM. With
such high dewpoints already in place ahead of this front, lows
will likely only be able to drop into the 71 to 75 degree range in
many locations (maybe not even that low since winds may stay
between 2 and 6 mph overnight in many locations).

Shower and thunderstorm chances were raised due to increased shear
seen in upstream soundings. The pooling of such high dewpoints
also will help to keep instability in place much of the night.
However, given the fairly weak nature of the lift, kept chances
only between 30 and 50 percent towards midnight into the 2 to 4 AM
period.

&&

.SHORT TERM...
(Monday through Tuesday Night)
Issued at 236 PM CDT Sun Jun 23 2024

Northwest flow aloft will persist into Monday, but upper ridging
will begin to push back into the region for Tuesday. Although,
this will be short-lived as an upper shortwave looks to move over
the Mississippi Valley and towards the Tennessee Valley Tuesday
night. At the surface, the cold front that brought low chances of
showers in the near term will move to our south. High pressure
will build in behind it and progress southeastward over the
Appalachians through Tuesday. Overall, no rain chances are
anticipated Monday through Tuesday evening. Very low chances
(10-15%) of showers return to northwest Alabama and portions of
southern middle Tennessee late Tuesday night into early Wednesday
morning ahead of a system slated to move through the area on
Wednesday (discussed in the section below).

It will be hot early next week as high temperatures are expected
to reach the mid to upper 90s. Continued elevated moisture will
cause "feels like" temperatures (heat indices) to be in the mid
90s to around 100 degrees on Monday. It`ll be a bit warmer on
Tuesday, with heat indices forecast to reach the mid 90s to around
102 degrees east of I-65 and between the upper 90s to around
103-104 degrees on Tuesday (perhaps a few areas around 105 in far
northwest Alabama). While these values are below Heat Advisory
criteria, we urge caution. Remember heat safety! Wear loose-
fitting, light-colored clothing, take frequent breaks in the
shade, and stay hydrated! Also, take caution for your pets as
well! Be cautious of the hot pavement, make sure they have ample
water and shade, and limit their time outdoors. The aforementioned
cold front will bring a slight reprieve Monday night, allowing
lows to dip into the mid to upper 60s. However, warm conditions
return Tuesday night with lows in the lower 70s.

&&

.LONG TERM...
(Wednesday through Saturday)
Issued at 1255 AM CDT Sun Jun 23 2024

A shortwave and possibly MCS in the central Plains will arrive in
the TN valley Tuesday night into Wednesday, which could factor
into our temperature forecast which right now says lower to middle
90s. However, PoPs will be increasing to the 30-50% range
Wednesday into Wednesday night. Although sustained large scale
heavy rain is not foreseen at this point, a few areas of 0.25-0.50
inch totals look obtainable. This will be followed by a weakening
frontal passage Wednesday night into Thursday morning. Notice I
didn`t even mention the word cold. Southerly low level flow will
develop Friday into Saturday, bringing sustained higher dew points
in the 70s along with the hot temperatures, thus increasing the
potential for excessive heat index values and risk into next
weekend.

&&

.AVIATION...
(06Z TAFS)
Issued at 1039 PM CDT Sun Jun 23 2024

Variable winds around 4 knots are expected much of the TAF period
at the terminals. This should keep fog at bay at the terminals. A
tempo group was included between 6Z and 9Z in case scattered
storms make it to the terminals. MVFR CIGS and some gusts to 20
knots could occur if a -TSRA impacts the terminals. A front
should pass through the terminals just after daybreak, providing
predominantly northerly winds at the terminals of 5 knots to 10
knots.

&&

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

$$

NEAR TERM...KTW
SHORT TERM....26
LONG TERM....17
AVIATION...KTW