210
FXUS64 KHUN 052250
AFDHUN

Area Forecast Discussion
National Weather Service Huntsville AL
550 PM CDT Sat Apr 5 2025

...New AVIATION...

.NEAR TERM...
(Rest of Today Through Sunday)
Issued at 1205 AM CDT Sat Apr 5 2025

Temperatures have climbed into the upper 70s to around 80 degrees
at this hour. Very moist southerly flow is keeping muggy conditions
in place with dewpoints remaining in the mid to upper 60s across
northern Alabama and southern middle Tennessee. This is all
occurring ahead of a strong cold front that stretches from central
Indiana SW across extreme SW Missouri and through Arkansas into
eastern Texas. Cloud cover should keep highs in the lower to mid
80 in most areas this afternoon.

Two main areas of showers or convection has been occurring so far
today ahead of the earlier mentioned cold front. One area of
convection that extends from NW Mississippi into western
Tennessee. An elevated mixed layer has been helping to keep that
activity much weaker than on previous days. This EML layer will
likely help to keep activity from intensifying significantly.

Further west a much more intense line of strong to severe
thunderstorms has developed over central Arkansas SSW into NW
Louisiana. As this line of thunderstorms, aided by much more
intense lift in mid and upper levels near/ahead of the frontal
boundary, moves into NW Mississippi over the next 2 to 3 hours,
it should be able to break that cap and tap into a relatively
untouched airmass. This should enable it to continue to develop as
it pushes east this afternoon.

Earlier mesoscale model guidance arrival of this line into
northwestern Alabama is suggested by several mesoscale models
again today. Based on the forecast and radar evolution so far this
morning, this looks very reasonable. Expect this line to move
into NW Alabama around 6 PM.  Although a few models increase
850 mb winds to between 40 and 50 knots and mix up to that before
convection arrives late this afternoon, there is not enough
consistency to feel comfortable issuing a Wind Advisory today.
Winds will be very breezy from the south to southwest though
between 10 and 15 mph gusting up to 30 mph at times. Helicity will
not be too high, but enough given strong shear and moderate
instability to produce some tornadoes (possibly a strong tornado)
as it moves into NW Alabama. Damaging winds and to a lesser extent
large hail also look possible.

These same models then push the line of strong to severe storms
east into the early evening hours to around or just east of the
I-65 corridor. Several models show this line weakening between 9
and 10 PM. This could leave a outflow boundary (focusing area for
additional convection/heavy rainfall) in place that could
maintain itself somewhere in northern Alabama overnight. This
could limit more widespread severe weather north of it (especially
damaging winds and tornadoes). However, south of it regardless
severe weather will be possible, as the actual cold front moves
into northern Alabama and southern middle Tennessee overnight into
Sunday morning. Damaging winds and more spin-up type tornadoes
are expected more so with this second round of activity.

The multiple rounds of storms and heavy rainfall hinted at by
models suggest a heightening flash flooding and flooding threat
setting up especially overnight into Sunday morning. Bumped up
rainfall totals through Sunday to between 2 and 4 inches with
locally higher amounts possible. A few models solutions show as
much as maybe 3-6 inches with locally higher amounts, but for now
will not go that high. However, given this heightened concern and
a few mainstem river points forecast to reach flood stage, a Flood
Watch was issued from 6 PM tonight through 6 PM on Sunday.

&&

.SHORT TERM...(Sunday night through Tuesday)
Issued at 1205 AM CDT Sat Apr 5 2025

Temperatures will take a dive into 40s overnight on Sunday into
Monday morning. Lingering cloud cover will help keep highs later
that day in the mid 50s to around 60 degrees.

The cold change will continue Monday night, with lows chilling
into the mid/upper 30s. Highs on Tuesday will only rise into the
mid/upper 50s.

&&

.LONG TERM...
(Tuesday night through Friday)
Issued at 1205 PM CDT Fri Apr 4 2025

Another chilly night Tuesday night with lows in the low/mid 30s.
This period will bring a risk of frosts and/or freezes to the
area. Highs on Tuesday will only rise into the mid/upper 50s.
Another chilly night Tuesday night with lows in the low/mid 30s.
This period will bring a risk of frosts and/or freezes to the
area.

Temperatures will moderate for the midweek, with highs Wednesday
rising into mid 60s, and into the lower 70s Thursday/Friday.
Another system will return shower and thunderstorm chances Thursday
into Friday.

&&

.AVIATION...
(00Z TAFS)
Issued at 550 PM CDT Sat Apr 5 2025

A line of strong to severe thunderstorms across MS is slowly
moving to the NE. These are expected to impact northern AL
starting around 04z and continue eastward overnight. Expect rapid
reductions in both vsby and cigs to IFR/MVFR as the line moves
through. Showers will continue behind the line through around
sunrise which will hold flight conditions in the high end IFR to
low MVFR. Still some uncertainty if the low stratus clears behind
the showers tomorrow morning or if they linger through afternoon.

&&

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

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

&&

$$

NEAR TERM...KTW
SHORT TERM....KTW
LONG TERM....RSB
AVIATION...GH