960
FXUS64 KHUN 091147
AFDHUN

Area Forecast Discussion
National Weather Service Huntsville AL
647 AM CDT Thu May 9 2024

...New AVIATION...

.NEAR TERM...
(Early This Morning and Today)
Issued at 330 AM CDT Thu May 9 2024

A mid/upr level shortwave embedded in quasi-zonal flow is
instigating shower/thunderstorm development early this morning
just to the north and west of the area. The activity is becoming
oriented in general W-E fashion, which is concerning for a couple
of reasons. First, the activity is oriented parallel to flow
direction, leading to training of cells and raising concerns for
localized flash flooding given the suitable moist environment
(PWATs ~1.5 to 1.7 inches) and ample broad scale ascent. Second,
the southern extent of the activity is aligned generally along an
old boundary that was draped across the area from previous
convection, thus potentially amplifying the low-level shear
available. Due to the continuing risk for tornado development, a
TOR Watch was just issued at ~300 AM CDT. Otherwise, cold pool
development and the potential for localized congealing cold pools
will provide a risk for strong/damaging winds along portions of
the evolving line of thunderstorms. Some wind gusts in excess of
50 kts have been noted already earlier this morning. This activity
will move across the area during the remainder of the morning,
perhaps clearing to our ESE around midday. Nevertheless, people
should remain aware of this second bout of precipitation moving
into the area this morning, in case they`re out and about for
clean-up and S&R activities.

A break in activity is expected this afternoon and some clearing
of clouds are expected to occur, with highs expected to warm
mainly in the low/mid 80s across the area.

&&

.SHORT TERM...
(Tonight through Sunday)
Issued at 330 AM CDT Thu May 9 2024

Another short wave is expected to pass across the region tonight,
but the better dynamic lift is expected to be to our south.
Isentropic progs indicate some lift/saturation aloft over our area
during the evening, and peaking overnight. However, there is
disagreement among regional/global models over the degree of
saturation in addition to lift/instability. POPs were kept rather
low (20s to 30s) for the nighttime period due to the uncertainty
with the northern extent of precipitation.

A shortwave trough digging southward into the Grt Lakes early
this morning will phase with a Northern Plains trough and carve
out a broader long wave trough in the eastern CONUS on Friday. As
a result a cooler, continental air mass will move into the TN
Valley late tonight and Friday. This eastern CONUS trough pattern
will tend to be maintained through Sunday, with slightly cooler
than normal temperatures through the period. Successive shortwave
maxima rotating around the western flank of the parent upr trough
could bring a bout or two of increased cloudiness, but chances
appear too low for any RA/SHRA to include in the forecast at this
time.

&&

.LONG TERM...
(Sunday night through Wednesday)
Issued at 330 AM CDT Thu May 9 2024

A partially closed upr low in the West CONUS will be ejected
eastward as heights begin to fall in the northern Rockies from
late Sunday into Monday. Moisture advection/ascent ahead of the
pending upr trough could begin to bring rain to the area as early
as Monday morning. Instability will increase gradually on Monday,
but forecast thermal profiles just appear marginally unstable at
this time, limiting updraft strength and severe potential. This
trough may become partially closed again as it makes its way
eastward across the OH/TN Valley regions, with chances for
showers/thunderstorms continuing into Wednesday.

&&

.AVIATION...
(12Z TAFS)
Issued at 645 AM CDT Thu May 9 2024

A line of SHRA/TSRA is moving slowly SWRD across the area and is
expected to continue impacting KMSL and KHSV thru ~14Z. A line of
+TSRA have just moved into KMSL and are expected to continue there
after 12Z with predom predom MVFR/IFR thru 13Z. An end to
precipitation and a return to VFR conditions is expected after
14Z, although gusty winds are expected to develop at both sites.
However, the return of gusty winds could be modified/delayed by
the potential for lingering rain conditions. Lighter, gradually
veering winds are expected to return by ~02Z.

&&

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

$$

NEAR TERM...KDW
SHORT TERM....KDW
LONG TERM....KDW
AVIATION...KDW