640
FXUS64 KHUN 132348
AFDHUN

Area Forecast Discussion
National Weather Service Huntsville AL
648 PM CDT Sat Jul 13 2024

...New AVIATION...

.NEAR TERM...
(Tonight)
Issued at 1238 PM CDT Sat Jul 13 2024

Any isolated convection that remains early this evening should
dissipate around sunset. Overnight lows will be in the lower 70s
for nearly the entire area. The only upper 60s would likely be
limited to the highest elevation of Lookout Mountain in eastern
DeKalb County.

&&

.SHORT TERM...
(Sunday through Monday Night)
Issued at 1238 PM CDT Sat Jul 13 2024

The weak vorticity center in eastern TX into northern LA/southeast
AR is forecast to lift northeast into northern MS and AL Sunday
and linger through Tuesday. This will continue to erode the
already weak capping inversion. Thus, we will maintain a 10-15%
PoP Sunday once again for isolated convection, and slowly increase
those PoPs into Monday, especially for the southern counties in
our forecast area. Steep low level lapse rates will create a
favorable environment for gusty winds with associated downdrafts.
Will go with near persistence temperature forecasts with highs in
the middle 90s to around 100. With strong mixing, dew points will
continue to be halted in the upper 60s to around 70 during the
afternoon hours, producing heat index values below 105 degrees for
most areas.

&&

.LONG TERM...
(Tuesday through Friday)
Issued at 417 AM CDT Sat Jul 13 2024

The most recent suite of global models suggests that conditions
on Tuesday will be very similar to Monday, with highs in the m-u
90s, heat indices in the 100-105F range and a 20-30% coverage of
afternoon showers and storms (which will likely be slow-moving and
capable of producing heavy rainfall in localized areas). By
Wednesday, however, our region will experience increasing
influence from an amplifying northern stream trough, which is
predicted to spread northeastward from Ontario into the Canadian
Maritime provinces by Thursday night/Friday morning. The cold
front related to this trough is expected to advance southeastward
during the middle portion of the week, with the prefrontal wind
shift axis expected to slowly cross the TN Valley at some point
Wednesday night or Thursday. A higher (60-80%) POP for showers
and thunderstorms is warranted as early as Wednesday afternoon
given the position of the front to our north and strengthening WNW
flow aloft. The greater coverage of convection will likely
continue on Wednesday night/early Thursday morning, before
becoming focused to the south/east of the wind shift (across our
southeastern zones) on Thursday afternoon. Due to some uncertainty
regarding the location of the front before it eventually stalls,
we will maintain a medium chance POP in the southeastern portion
of the CWFA on Thursday night and Friday. Fortunately, a modest
coverage of clouds and precipitation should keep highs in the
u80s-l90s from Wednesday-Friday, lowering the heat risk region-
wide.

&&

.AVIATION...
(00Z TAFS)
Issued at 648 PM CDT Sat Jul 13 2024

VFR weather should continue across the area. Strong daytime
heating and resultant instability has resulted in a few showers
forming over the past few hours. Shower activity should fade as we
go into the later evening and overnight. Patchy fog cannot totally
ruled out before daybreak in and near locations that received
measurable rainfall. More strong heating should result in more
CU/TCU forming towards Sun afternoon. Confidence is too low on
adding showers Sun afternoon this issuance.

&&

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

$$

NEAR TERM...17
SHORT TERM....17
LONG TERM....70
AVIATION...RSB