Area Forecast Discussion
Issued by NWS Huntsville, AL

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111
FXUS64 KHUN 150450
AFDHUN

Area Forecast Discussion
National Weather Service Huntsville AL
1150 PM CDT Fri Jun 14 2024

...New AVIATION...

.NEAR TERM...
(Rest of tonight)
Issued at 1005 PM CDT Fri Jun 14 2024

Winds over the past few hours have gone calm across many locations
in northern Alabama and southern middle Tennessee. This and clear
skies have allowed temperatures to drop into the 75 to 85 degree
range in most locations.

An approaching dry front will be the main player in overnight
lows tonight. It could bring some partly cloudy skies to the area
during the overnight hours especially. Through midnight though,
expect mainly clear to mostly clear skies. This and some initially
drier air advecting in from the north to northeast through 1 AM,
should continue to allow temperatures to drop off into the mid to
upper 60s east of the I-65 corridor.

With some more prevalent partly cloudy conditions expected
overnight and strong moisture advection right ahead of a front
moving into southern middle Tennessee or northern Alabama towards
daybreak, it will be a muggy start to Saturday with temperatures
likely only dropping off into the 70 to 75 degree range west of
the I-65 corridor. Further east, temperatures should be able to
drop into the mid to upper 60s around midnight (as mentioned
earlier) before climbing a bit as the front moves to around the
Tennessee River or slightly further north. Winds should pick up
then as well to between 5 and 10 mph as the front pushes into the
area towards daybreak. Expect some fog to develop, mainly south of
the Tennessee River between midnight and 4 AM, before winds near
the front likely help to get rid of some patchy/areas of fog.

&&

.SHORT TERM...
(Saturday through Monday)
Issued at 200 PM CDT Fri Jun 14 2024

A partially closed low will phase with a broad but low-amplitude
trough in the west today/tonight. This will lead to downstream
ridge development in the OH/TN Valleys through the weekend. This
will tend to halt the progression of a southward moving cold front
in the OH Valley observed in model analyses and sfc observations.
Most of the drier air and lower dew points poleward of the front
will likely not tend to make it into our area, except perhaps for
far NE portions of the area later Saturday.

The upr ridge and developing sfc high will continue to translate
eastward to the eastern side of the Appalachians on Sunday. Flow
around the sfc high will bring SSE winds and a slight increase in
low-lvl moisture into the area on Sunday. This increase may be
sufficient, when combined with heating of elevated terrain and
along differential heating boundaries, to ignite some isolated
showers/thunderstorms on Sunday afternoon. Sounding
thermal/moisture profiles suggest some strong wind potential with
high moisture loading (PWs ~1.7 to 1.9 in) and inverted-V low-lvl
profiles. Mid-lvl dry could aid local wind development potential,
but also serve to inhibit stronger cell growth. So, the threat
looks rather minimal at this time, nevertheless worth mentioning
here.

Otherwise, the main story for the weekend will be the increasingly
hot conditions underneath the building upr ridge. Temperature
conditions per heat indices and wet-bulb globe temps may be close
to heat advisory criteria, especially in/around the HSV and Quad-
cities areas on Sunday afternoon.

&&

.LONG TERM...
(Sunday night through Thursday)
Issued at 303 AM CDT Fri Jun 14 2024

Muggy conditions will continue Sunday night with lows only in the
low/mid 70s. A deep southerly flow will help return more moisture to
the area, with area dewpoints on Monday rising to around 70. This
moisture will also result in an increase in cloud cover, which should
put a slight damper on very warm to hot conditions that have likely
occurred over the weekend. Highs to start the new work week should
rise into the lower 90s, with heat index values in the mid/upper 90s.
Daytime heating and resultant instability from higher moisture
values, will bring lower end (20-30%) chance of showers and
thunderstorms to the valley Mon afternoon. Strong upper level high
pressure over the region will help warm the mid troposphere, which
should help reduce rain chances Mon evening.

This strong and warm upper ridging is forecast to amplify over the
states north and east of here (Mid Atlantic to New England) in the
course of the new week. The 500mb reflection of the upper high has
maximum height values near the 600 decameter range Wed/Thu from
Pennsylvania to New Hampshire. With lower heights more to the south
and west, our daily high temperatures for Tue/Wed/Thu should range
mainly in the lower 90s, and lows in the lower 70s. Somewhat lower
levels of moisture should result in dry conditions for this
timeframe.

&&

.AVIATION...
(06Z TAFS)
Issued at 1150 PM CDT Fri Jun 14 2024

Other than a dry and weak frontal boundary dropping into the area
early Sat morning, high pressure to the east should help maintain
VFR conds thru the TAF period. Light/var winds are also expected
thru the afternoon/evening hrs Sat.

&&

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

$$

NEAR TERM...KTW
SHORT TERM....KDW
LONG TERM....RSB
AVIATION...09