LMK issues Area Forecast Discussion (AFD) at Jul 22, 9:31 PM EDT375
FXUS63 KLMK 230131
AFDLMK
Area Forecast Discussion
National Weather Service Louisville KY
931 PM EDT Mon Jul 22 2024
.KEY MESSAGES...
* Isolated to scattered shower and storm chances are expected to
exist every day through the upcoming week.
* Slow movement of any shower or storm could result in locally
heavy rainfall amounts.
&&
.UPDATE...
Issued at 931 PM EDT Mon Jul 22 2024
Precip activity has decreased in the last hour or so, and any
lingering showers with embedded thunder should diminish shortly as
we become more stable. The ongoing forecast remains in good shape,
with rain chances ending within the next hour or so. The main
concern for the overnight will be fog development. Saturated grounds
after recent heavy rainers, along with winds near calm, will support
patchy dense fog, and possibly even some areas of dense fog. The
guidance this evening has been keying in on counties west of I-65
for having more coverage of fog, but still expect to see reduced
visibility in some regard across most of the forecast area
overnight. One limiting factor could be if cloud cover lingers
longer than expected. Overall, the forecast is in good shape, with
the only changes being to update and slightly expand fog mention in
the grids. Forecast products are sent.
&&
.SHORT TERM /THROUGH TUESDAY/...
Issued at 331 PM EDT Mon Jul 22 2024
An upper closed high is sitting over the Southwest. This is pushing
an upper ridge north into Canada before it drops due south through
the Plains before flowing from Texas to the North Atlantic, forming
a positively tilted trough west of the Mississippi and Ohio Valleys.
Stacked high pressure remains over the Atlantic. Southern Indiana
and central Kentucky sit in-between this upper trough and Atlantic
high that continues to funnel moisture from the Gulf of Mexico and
Atlantic northward. Precipitable water values today range from
around 1.4" in southern Indiana to around 1.8" in southern Kentucky.
With surface pressure gradients being weak, surface winds are light
and fairly variable. Diurnal heating is creating instability causing
isolated to scattered showers and thunderstorms to develop over the
area. Model soundings show a stable mid-level which should help
limit thunderstorm vertical growth, and weak shear will limit severe
potential. With that said, the main concern is flooding due to
possible heavy rainfall rates and slow moving cells.
Tonight, winds are expected to go calm as skies try to clear. We
likely won't lose all of our cloud cover, but the clearer we become,
the better the radiative cooling. This is expected to cause fogging,
especially in areas that have wet soils from earlier rainfall and
see clear skies. Lows should range from the mid 60s to near 70.
Tomorrow morning, a warm front will drive north into southern
Kentucky from Tennessee. This will likely push precipitable water
values to near or just over 2" with dew points in the low 70s. The
CAMs show a line of showers and thunderstorms moving northward with
the front. This activity could help to limit high temperatures to
near 80 south of the Kentucky parkways. North of the parkways,
temperatures will likely climb from the low 80s to mid 80s farther
north.
&&
.LONG TERM /TUESDAY NIGHT THROUGH MONDAY/...
Issued at 331 PM EDT Mon Jul 22 2024
The upper level trough that has been oriented from the southwest to
the northeast across the Great Lakes to the southern Plains the last
couple of days will finally begin to lift and work eastward by the
end of the week. This is due to the ridge across the western CONUS
strengthening and building to the northeast as a strong upper low
works in over the Pacific Northwest. As the trough works eastward it
will push a weak sfc low across the Great Lakes which will swing a
cold front out of the Upper Midwest and into the Ohio Valley by
Thursday. Scattered showers and storms will be possible Wednesday as
a weak embedded shortwave impulse works across the Tennessee Valley
Wednesday morning into Wednesday afternoon. We will then see another
round of showers and storms Wednesday night into Thursday as the
cold front approaches from the north. While the threat of severe
remains low due to a lack of wind shear, PWAT values will remain
between 1.50" to 1.90" ahead of the approaching cold front, so heavy
rainfall and localized flooding will remain the main concern. Highs
will remain in the low/mid 80s for both Wednesday and Thursday with
lows in the mid/upper 60s.
Friday into the weekend continues to feature disagreement in the
deterministic models. While the ECMWF continues to be drier pushing
the cold front further south with mainly dry weather through this
period, the GFS stalls out the boundary and lifts it back north
keeping showers and storms around each day through the weekend. For
now, we continue to go with the NBM which seems to be a good blend
of both solutions. This splits the CWA in half with the highest
chance of scattered showers/storms 20-30 percent across the southern
half while keeping it dry to the north. Temperatures are also warmer
as the western ridge builds in over the region for the weekend.
Highs make a return to the upper 80s to low 90s and lows in the
mid/low 60s until Monday morning when they warm into the mid/upper
60s.
&&
.AVIATION /00Z TAFS THROUGH 06Z THURSDAY/...
Issued at 721 PM EDT Mon Jul 22 2024
Very slow moving scattered showers and storms have been on going
since earlier this afternoon, but should diminish in coverage as the
daytime heating is lost. Due to the heavy rain in some areas, along
with near-calm winds later tonight, can expect fog to be an issue
for some overnight and tomorrow morning. BWG and HNB have the
highest chance for vis restrictions, but some patchy fog will be
possible at the other terminals as well. There's also a signal for
some low stratus as well, so some areas may be impacted by the low
cigs instead of vis. After sunrise, improving conditions will take
place, leading to VFR flight cats at all terminals.
&&
.LMK WATCHES/WARNINGS/ADVISORIES...
KY...None.
IN...None.
&&
$$
UPDATE...CJP
SHORT TERM...KDW
LONG TERM...BTN
AVIATION...CJP
Source:
LMK issues Area Forecast Discussion (AFD) at Jul 22, 9:31 PM EDT---------------
If I'm using your data in a way that is against your terms please email the team at "threatweb@pupswoof117.com"! I am a bot who will not respond in the comments at all and is only designed to post RSS feeds!
