711
FXUS64 KHUN 140555
AFDHUN

Area Forecast Discussion
National Weather Service Huntsville AL
1255 AM CDT Tue May 14 2024

...New AVIATION...

.NEAR TERM...
(Tonight)
Issued at 802 PM CDT Mon May 13 2024

A quiet evening now in progress after any lingering drizzle or
light rain ended late this afternoon. Temperatures are holding
nearly steady in the middle 60s to near 70 with southeast wind of
5-10 mph at some locations, others less than 5 mph. We will be
watching a 5h low just south of Kansas City and a trailing
shortwave trough axis moving only eastward into central MO and AR
by morning. UVVs will increase in advance of this wave, along with
steepening lapse rates and moisture transport into the MS Valley.
Showers and a few thunderstorms in southern MO and north and west
central AR will advance east northeast tonight, but additional
showers and thunderstorms are projected to develop in west TN,
north MS and advecting into north AL and southern middle TN
after 06-08Z. Our current forecast has this in mind, and will not
adjust from it significantly.

&&

.SHORT TERM...
(Tuesday through Thursday)
Issued at 135 PM CDT Mon May 13 2024

A fairly widespread coverage of showers and elevated
thunderstorms will likely be in progress across the region around
12Z Tuesday, but should progress northeastward and out of the
region by mid- morning. Subsequent breaks in the early morning
stratus layer will allow for modest destabilization to occur late
tomorrow morning, with additional (but more scattered)
thunderstorm activity expected to develop to the west of our
region (across western TN/northern MS) by 16-18Z. This activity
should spread eastward through the TN Valley tomorrow afternoon,
and will likely represent our greatest risk for strong-severe
thunderstorms (warranting a Marginal Risk from SPC). The
combination of mid-level WSW winds in the 35-45 knot range and
MLCAPE perhaps as high as 1500-2000 J/kg in portions of the
forecast area will favor organized convection, which may initially
evolve as multicell clusters before growing into a broken line.
Large hail/locally damaging winds and frequent lighting will be
the main threats with this activity.

Present indications are that afternoon convection will gradually
weaken and spread eastward (out of the forecast area) early
Tuesday evening, but with additional showers possible ahead of a
surface trough (extending southward into our region from a low
tracking through the OH Valley), we will maintain a low-medium
chance POP region-wide through 6Z. A third and final round of
showers (and perhaps a few storms) will likely occur on Wednesday
with the passage of a weak cold front, but with a mid-level ridge
likely to be crossing the region in the wake of the shortwave
trough (noted above), storm coverage and intensity will be lower
(compared to Tuesday). Clearing skies and calm winds are expected
on Wednesday night as a narrow ridge of surface high pressure
noses into the region from the north, and this may support the
development of fog early Thursday morning as temps fall into the
u50s-l60s.

&&

.LONG TERM...
(Thursday night through Monday)
Issued at 342 AM CDT Mon May 13 2024

After brief upper ridging and surface high pressure that will
keep rain out of the forecast on Thursday will come what seems
like a "rinse and repeat" storm system (similar to the one
discussed above) for Friday and into Saturday. Upper ridging will
be pushed east as a trough makes its way over the Mississippi
Valley through late week. At the same time, a surface low pressure
system is shown to develop over southwestern Texas around midweek
and then traverse to the northeast towards the ArkLaTex region by
early Friday. Anticipating this system to continue its
northeastward trajectory that will take it over northern Virginia,
Delaware, and Maryland by Saturday morning. Chances of showers
and storms are forecast to increase overnight into Friday morning.
Unsettled weather will then likely persist through the weekend,
with the highest chances (60-70%) of showers and storms
anticipated Friday afternoon. While enough instability and shear
will be present for thunderstorm development Friday afternoon and
evening, the better upper dynamics and thermodynamics once again
look to be to our south (much like the storm system in the
near/short term). Overall, at this time, confidence in any severe
weather is low because of this. However, we will continue to
monitor this system in case the trajectory of the low tracks
northward (increasing the severe potential). Highs will generally
top out in the lower to mid 80s each day except for Friday (upper
70s) due to the increased coverage of showers and storms. Lows
will remain in the lower to mid 60s through the weekend.

&&

.AVIATION...
(06Z TAFS)
Issued at 1255 AM CDT Tue May 14 2024

Generally inclement flying weather will continue over the area for
the TAF, with CIGs at or below MVFR. Scattered to numerous showers
and thunderstorms extending from near KMEM to KGLH will advance to
the ENE overnight, and begin impacting NW AL before daybreak Tue.
Timing from recent model runs have showers over KMSL ~09-10Z with
CIG reductions to IFR at times. This activity should reach KHSV a
couple of hours later. Did not add thunder before daybreak, but
cannot rule out early isolated TSRA. Chances for thunder are higher
in the late morning as a more organized area of convection reaches
NW AL, then moves eastward across the area in the afternoon. Some
of this convection could produce strong gusty outflow winds, and
reduced CIG/VSBY for a short time. Lower chances of showers will
continue across the area this evening.

&&

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

$$

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