169
FXUS64 KHUN 221622
AFDHUN

Area Forecast Discussion
National Weather Service Huntsville AL
1022 AM CST Fri Nov 22 2024

...New AVIATION...

.NEAR TERM...
(Rest of Today)
Issued at 821 AM CST Fri Nov 22 2024

A strong shortwave was dropping southeast through the Smoky
Mountains and Piedmont this morning. Low level northerly flow has
brought a layer of clouds to southern middle TN into northeast
AL. These will tend to dissipate through the day as the wave
departs and heating/mixing ensues. High temperatures in the lower
50s valleys/middle to upper 40s Cumberland Plateau look good.
Morning soundings and a decreasing surface pressure gradient
indicate a less windy day than Thursday, but still with gusts of
20-25 mph at times.

&&

.SHORT TERM...
(Tonight through Sunday Night)
Issued at 246 AM CST Fri Nov 22 2024

As the previously mentioned pressure gradient relaxes this
evening and tonight, winds will also gradually subside. The main
concern tonight through early Saturday morning will be the
potential for freezing temperatures and possibly frost. While
recent thoughts and trends pinpointed tonight into early Saturday
with decent potential for our first freeze of the season, current
Hi-Res model guidance suggests greater cloud cover, hindering
better radiational cooling and resulting in warmer low
temperatures (generally in the mid to upper 30s or so). Meanwhile,
the NBM shows less clouds and colder temperatures closer to and
around freezing (as has been the trend).

Ultimately, this model spread has resulted in lower forecaster
confidence in freezing temperatures; however, did decide to issue
a Freeze Watch for our northern Alabama counties from 12AM tonight
until 8AM Saturday morning to account for some areas possibly
dipping into the lower 30s. Furthermore, if the NBM solution is
realized, more areas will likely dip to near/right at freezing.
This will be monitored through the day today and tonight,
especially if trends point towards the need to upgrade the Freeze
Watch to a Warning. Nonetheless, make sure to take special care of
and cover sensitive plants. Also, be prepared for the colder
temperatures by bundling up if heading outside tonight/tomorrow
morning.

From Saturday through Sunday night, a warming trend will take
place as upper ridging and surface high pressure takes hold. No
rain is forecast, but highs will warm from the 50s on Saturday to
the lower to mid 60s on Sunday. Lows will follow suit, with
temperatures in the 30s Saturday night and warming into the mid
40s to around 50 degrees by Sunday night.

&&

.LONG TERM...
(Monday through Thursday)
Issued at 246 AM CST Fri Nov 22 2024

A more active period will set up beginning Monday as upper ridging
shifts east of the area and a trough nears from the central Plains.
Will see moisture increase on Monday ahead of a cold front tied to
the aforementioned trough and will result in the warmest day of the
forecast period with highs reaching the upper 60s to lower 70s Monday
afternoon. Will introduce low chances (20-30%) for rain Monday
afternoon with high chances (70-80%) during the evening and
overnight hours. Moisture looks to be a bit limited over the area
with this system, so overall rainfall amounts look to be below 1/4"
at this time. With limited instability, thunder chances remain very
low at this time.

The forecast for Tuesday looks cooler but dry at this time, with
highs ranging from the mid 50s to low 60s. Lows will drop into the
upper 30s/lower 40s Tuesday night into Wednesday, which is when our
next system shifts east through the Plains and model guidance
diverges from there. While the GFS favors more of a heavy rain event,
the ECMWF takes the sfc low slightly farther north and puts us more
in the warm sector. The exact track of the sfc low will make a big
difference between just rain and potentially strong storms, but we
continue to have very low confidence on how this system will set up
over our area. What we do have confidence in is that the area will
see at least some rainfall late Wednesday into Thursday and cooler
temperatures will follow. Stay tuned for updates as the late-week
system gets closer in time.

&&

.AVIATION...
(18Z TAFS)
Issued at 1022 AM CST Fri Nov 22 2024

VFR flight weather conditions will last into this evening.
North to northwest winds will gust at 15-20kt this afternoon.
There is a medium to high chance that low ceilings of 015-025agl
(MVFR) spread south through southern middle TN into parts of north
AL, including KHSV. It is a lower chance at KMSL. Conditions are
forecast to improve back to VFR by 16Z, but there remains some
uncertainty on this clearing trend, so updates may be needed.

&&

.HUN WATCHES/WARNINGS/ADVISORIES...
AL...Freeze Watch from late tonight through Saturday morning for
     ALZ001>010-016.

TN...None.
&&

$$

NEAR TERM...17
SHORT TERM....26
LONG TERM....25
AVIATION...17