422
FXUS64 KHUN 110908
AFDHUN

Area Forecast Discussion
National Weather Service Huntsville AL
408 AM CDT Tue Jun 11 2024

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

.NEAR TERM...
(Today)
Issued at 408 AM CDT Tue Jun 11 2024

Northwesterly flow aloft of 35-45 knots continues across the TN
Valley early this morning, enabling scattered high-level clouds to
spread southeastward over the region. Although the translucent
cirrus layer has had little impact on radiational cooling, a light
NNE wind has, with temperatures currently in the m-u 50s where
calm flow is observed. Patchy fog will be possible in these
locations through 12-13Z. Over the course of the day, mid-level
winds will weaken considerably as a trough to our northeast begins
to lift out into the western North Atlantic and a deamplifying
shortwave ridge spreads eastward in advance of a weak southern
stream disturbance that will track through the Red River Valley of
OK/TX. In the low-levels, light NNW winds will continue to advect
a slightly cooler/drier airmass southward into the region as a
surface high translates southeastward from the western Great Lakes
into the Upper OH Valley. With abundant sunshine, highs will once
again range from the m-u 70s atop the Cumberland Plateau to the
lower 80s in the valley.

&&

.SHORT TERM...
(Tonight through Thursday night)
Issued at 408 AM CDT Tue Jun 11 2024

Latest short term model consensus suggests that the southern
stream disturbance (noted above) will spread southeastward into
the central Gulf of Mexico over the course of the short term
period, as a strong 500-mb subtropical ridge (initially centered
across northern Mexico) builds eastward across the southern Plains
and southeastern CONUS. Subsidence beneath the expanding mid-
level anticyclone will contribute to further drying of profiles
aloft, and with only gradual modification of boundary layer
dewpoints anticipated (given the projected orientation of broad
surface ridge across the region), dry conditions will continue
along with a notable warming trend in afternoon high temperatures,
which should reach the u80s-l90s by Thursday.

&&

.LONG TERM...
(Friday through Monday)
Issued at 408 AM CDT Tue Jun 11 2024

The center of the mid-level high is predicted to become centered
directly across the TN Valley by Saturday, with the warming trend
continuing as mostly sunny skies during the afternoon will support
highs in the mid 90s on Friday and mid/upper 90s on Saturday (but
roughly 5-10 degrees cooler both days atop the Cumberland
Plateau). Unfortunately, it appears as if low-level moisture will
begin to pool ahead of a weakening cold front that will drift
southward into the TN Valley before stalling on Friday
afternoon/evening as the parent surface low ejects northeastward
across Quebec, and the increase in dewpoints will result in heat
indices in the 95-99F range Friday and 98-102F range Saturday.

The 500-mb high will begin to shift east-northeastward into the
NC/VA vicinity on Sunday and Monday, allowing for a gradual
increase in deep-layer SSE flow across the TN Valley by early next
week. Although this configuration will eventually contribute to
gradual moistening of the atmospheric column (and a subsequent
increase in clouds and showers) this will likely not occur by
Sunday, and highs are forecast to reach the m-u 90s, with heat
index values in the 100-105F range. We have indicated a low
(20-30%) POP for showers and thunderstorms returning to most of
the region Sunday night/Monday, and have indicated lower afternoon
temps on Monday as a result of this. However, if the subtropical
ridge remains more influential (as indicated by several global
models), then the hot/dry pattern may continue for several
additional days next week.

&&

.AVIATION...
(06Z TAFS)
Issued at 1251 AM CDT Tue Jun 11 2024

VFR conditions will exist at the HSV/MSL terminals this TAF
period, with a few high-level clouds expected at times and a few
lower-level Cu possible during the peak of the diurnal warming
cycle on Tuesday. A NNE flow arnd 5 kts will persist overnight
(and reduce concern for nocturnal BR/FG development at the
airports) before backing to NNW and increasing a bit by 16Z. Winds
will become lgt/vrbl by 22Z.

&&

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

&&

$$

NEAR TERM...70/DD
SHORT TERM...70/DD
LONG TERM...70/DD
AVIATION...70/DD