895
FXUS64 KHUN 190855
AFDHUN

Area Forecast Discussion
National Weather Service Huntsville AL
355 AM CDT Wed Jun 19 2024

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

.NEAR TERM...
(Today)
Issued at 355 AM CDT Wed Jun 19 2024

An area of high altitude moisture from the tropics continued over
the area, resulting in generally cloudy skies. A potential
tropical system could form under these clouds over the southern
Gulf of Mexico. Any effects from this system should remain well to
our south. A strong upper level ridge over the Mid Atlantic had
maximum heights at 500mb of near 597 decameters over WV/VA. This
upper high will move a bit further to the north and amplify even
more to the upper 590s to 600 decameters, and help produce
unseasonably hot weather over much of the eastern and NE Lower-48.
This ridge should weaken somewhat and build more to the south in
the latter portion of the week. At the surface, a Bermuda high
centered over the NW Atlantic basin was bringing an ESE flow over
this region. 2 AM temperatures were mainly in the mid/upper 70s.

Mostly cloudy high clouds should continue today. But a steady ESE
flow of 5-10 mph overnight should increase into the 10-15 mph
range later today. Somewhat lower heights due to the upper high
drifting further to our NE should result in a "cooler" day for
Juneteenth, with highs in the upper 80s to around 90.

&&

.SHORT TERM...
(Tonight through Friday night)
Issued at 355 AM CDT Wed Jun 19 2024

Low temperatures tonight should cool to around 70 as the upper
cloud deck slowly thins. With less cloud cover and the upper
high heading southward, higher heights/thicknesses and a strong
sun should return very warm to hot conditions on Thursday, highs
rising into the lower 90s. Thu is also the first day of summer
(which starts around 351 PM CDT). Similarly mild conditions Thu
night with lows around 70. Friday, the first full day of summer
will feel like summer, with highs warming into the low/mid 90s.
Corresponding heat index readings should range in the 90s both
Thu/Fri. And with high pressure controlling the weather, no
precipitation is expected into early Saturday.

&&

.LONG TERM...
(Saturday through Tuesday)
Issued at 355 AM CDT Wed Jun 19 2024

Guidance from the 0Z suite of global models suggests that a strong
mid-level high will be centered across the TN Valley at the beginning
of the extended forecast period. However, the subtropical ridge is
predicted to retrograde with time this weekend (becoming centered
across eastern NM/western TX by 0Z Monday) as a northern stream
trough digs east-southeastward along the U.S-Canadian border and into
the eastern Great Lakes. Although this evolution will result in a
gradual increase in NW flow aloft for the TN Valley, highs will still
manage to reach the m-u 90s in the valley on both Saturday and
Sunday (u80s in elevated terrain), with heat indices in the 98-102F
range as dewpoints creep back up into the u60s-l70s. Due to less of
an impact from subsidence, a few afternoon/evening showers and
thunderstorms will also return to the southeastern portion of the
CWFA Saturday, with a slight increase in spatial coverage for all
areas on Sunday.

There is reasonably good agreement among the models that a weak cold
front (attached to the northern stream trough) will drop southward
through the region on Monday, and we have indicated our highest POPs
for the extended period on this day. Frontal convection will likely
end south of the TN River Monday evening, with the front expected to
decelerate and become increasingly oriented in a NW-SE fashion to the
west of the forecast area on Monday night/Tuesday. Although a
slightly drier airmass may spread into the northeastern portion of
the region, there is some uncertainty regarding precisely where the
front will lie, and we have kept a low (~20% POP) intact for Tuesday.
High temperatures will change little (if at all) in the wake of the
front, but may be a couple of degrees cooler due to an increase in
cloudiness both days.

&&

.AVIATION...
(00Z TAFS)
Issued at 504 PM CDT Tue Jun 18 2024

VFR flight weather conditions are expected through the period with
east-southeast flow persisting.

&&

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

$$

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