679
FXUS64 KHUN 081146
AFDHUN

Area Forecast Discussion
National Weather Service Huntsville AL
646 AM CDT Mon Jun 8 2026

...New AVIATION...

.KEY MESSAGES...
Updated at 1209 AM CDT Mon Jun 8 2026

 - Excessive rainfall and flash flood risk persist through
   Tuesday.

 - Flood Watch Monday for areas north of the Tennessee River.

 - Heat Risk increases by late this week. Heat index values in the
   middle 90s to around 100 degrees Wednesday through Saturday.

&&

.NEAR TERM...
(Today)
Issued at 304 AM CDT Mon Jun 8 2026

A nondescript wave of low pressure (initially across the Mid-MO
Valley) will shift slowly northeastward over southern IA/northern
MO today in conjunction with a faster-moving shortwave trough in
the mid-levels. As this occurs, a subtle warm front extending
south-southeastward into the TN Valley will continue to advance
slowly northeastward early this morning, perhaps initiating
redevelopment of showers and thunderstorms in the 9-12Z timeframe
from the Lower-OH Valley southeastward into northern portions of
MS/AL/GA. Should this occur, the risk for Flash Flooding will
increase quickly (particularly in locations impacted by the
swath of heavy rain yesterday, where an Areal Flood Warning for
excessive runoff and rising river/creek levels remains in effect
through 7 AM). Otherwise, a thick layer of very low stratus clouds
will gradually expand across the region as temps descend into the
u60s-l70s within the very moist airmass locally.

As for the rest of the day, latest CAMs suggest that convection
will develop by 16Z across the western portion of the CWFA as the
first in a series of subtle low-level confluence axes within the
broad warm sector will provide sufficient convergence given the
abundance of moisture (PWAT values in the 2.1-2.2" range).
Although we will likely experience no direct impacts on deep-layer
vertical motions from the shortwave trough to our northwest, a
plume of steeper lapse rates along its southern flank will
contribute to higher CAPE (1500-2500 J/kg) compared to yesterday,
and for this reason we anticipate a significant increase in both
lightning and rainfall rates (due to convective enhancement).
Thus, the current Flood Watch (in effect from 6 AM - 8 PM) has
recently been expanded to include Cullman, Dekalb, Marshall and
Morgan counties, as thunderstorms should expand in coverage as
they spread slowly east-northeastward across our region.

&&

.SHORT TERM...
(Monday night through Wednesday)
Issued at 1209 AM CDT Mon Jun 8 2026

The upper trough axis will pivot more southeast Monday night into
Tuesday as the ridge builds a bit over the Ozarks. This system
generates clusters of convection over the lower OH Valley into
middle and western TN Monday night and into the TN Valley and much
of AL and GA into Tuesday as the trough shifts southeast. For
now, will not extend the Flood Watch past Monday, but this may
need to be reassessed depending on Monday`s rainfall. The upper
ridge will build east into TN/AL and MS by Wednesday, but will not
cap off at least diurnally driven convection, mainly in our
eastern counties. So low to medium chances remain in the forecast.
Temperatures will warm more significantly on Wednesday with highs
in the upper 80s to around 90. With dew points in the 70s, heat
index values will reach the middle to upper 90s (possibly 100 in
far northwest AL).

&&

.LONG TERM...
(Wednesday night through Sunday)
Issued at 1209 AM CDT Mon Jun 8 2026

The ridge across much of the southern and eastern CONUS will be
dampened as a wave of energy rounds the base of a trough in
southern Canada on Thursday and furthermore on Friday. On Friday,
the associated sfc low will be north of the Great Lakes, but the
cold front will drape down through the OH Valley and back into the
Mid MS Valley. Some models have the cold front dipping toes into
the TN Valley Friday night, while others are suggesting it stalls
out north of us and never makes it in. Will stick with guidance
for now with this, and that brings a medium chance (60%) of
showers and thunderstorms Friday. Otherwise, we will be under high
pressure throughout the rest of the extended forecast, but it
won`t feel like it. We`ll be trapped in with plenty of moisture
for diurnally driven convection each day (low to medium chances
20-50%).

We will also turn up the heat as temps reach the upper 80s/lower
90s on Thursday through Saturday and just in the upper 80s on
Sunday. It is important to note that this set up will also push
the heat index values into the upper 90s/lower 100s Thursday
through Saturday. Will monitor trends, but right now values are
below Heat Advisory Criteria. Regardless though, you will need to
practice heat safety because we do not feel acclimated to the high
heat and humidity for this long quite yet, so ensure that you
stay hydrated and slow down to prevent heat related illnesses.

&&

.AVIATION...
(12Z TAFS)
Issued at 646 AM CDT Mon Jun 8 2026

There have been no major changes to previous aviation forecast
reasoning, with an overcast MVFR stratus layer and patches of lgt
RA in place region-wide. Early development of convective cells is
expected btwn 12-16Z as the moist airmass begins to diurnally
destabilize ahead of a subtle sfc trough. Current thinking is that
coverage of TSRA will be greater today (compared to Sun), with
the timeframe of greatest concern for impacts from lightning and
torrential downpours coming btwn 16-22Z. There are indications
that a slightly drier airmass may infiltrate the region beginning
tomorrow evening. Thus, we will indicate no precipitation beyond
22Z, and advertise gradual scattering of the low cloud layer.
Prevailing sfc winds will remain from the SSE at 5-10 kts.

&&

.HUN WATCHES/WARNINGS/ADVISORIES...
AL...Flood Watch through this evening for ALZ001-005>010-016.

TN...Flood Watch through this evening for TNZ076-096-097.

&&

$$

NEAR TERM...70/DD
SHORT TERM...17
LONG TERM...JMS
AVIATION...70/DD