Area Forecast Discussion
Issued by NWS Louisville, KY

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FXUS63 KLMK 081711
AFDLMK

Area Forecast Discussion
National Weather Service Louisville KY
1211 PM EST Fri Nov 8 2024

...Updated Aviation Discussion...

.KEY MESSAGES...

*  Dry today with a mix of sun and clouds, and temperatures range in
   the 60s.

*  After a dry start to the weekend, widespread rain is forecast for
   Saturday evening through Sunday. 1 to 1.5" of rain expected for
   most.

*  Dry early next week, with the next chance for rain arriving
   midweek.

&&

.UPDATE...
Issued at 1016 AM EST Fri Nov 8 2024

Current forecast remains on track and only minor adjustments were
made to account for current observational trends. Light northeast
winds will keep the dry air advection over the area, clearing the
low-level cloud deck across the southern Kentucky. Meanwhile, upper-
level flow will transport cirrus clouds from the Mid Mississippi
across the Ohio Valley, but cloud optical depth should not block
solar radiation. As a result, maximum temps will climb to the mid
60s along the Ohio River to potentially around 70 in the south.

&&

.SHORT TERM /THROUGH TONIGHT/...
Issued at 306 AM EST Fri Nov 8 2024

Low stratus deck is bisecting Kentucky this morning, but very dry
air filtering in from the north is helping to push the cloud deck to
the south. Just about all of the region should clear out from the
low stratus deck this morning, but there`s a chance for the Lake
Cumberland region to hold on to the low clouds for a little later
than anywhere else.

Model soundings are a good representation of the dry column for
today, with the bulk of the dry layer below 400mb through the
afternoon, leading to a dry forecast for the entire area. Increasing
upper clouds will replace the low stratus later today, which will
keep a mix of sun and clouds in the forecast. Model soundings and
HREF cloud cover guidance have good agreement on this. Temps are
expected to range in the 60s, which will end up being a few degrees
above our normals for early November.

For tonight, sfc high pressure will be centered over the Great
Lakes, which will place us in a light NNE wind pattern in the lower
levels. A large occluding low pressure system over the Central
Plains will be spreading clouds out to the east, so we can expect to
see a continued increase in high level clouds over overnight. The
remarkably dry layer in the column with persist tonight, so a
completely dry night is forecast. Temperatures will range in the
40s, with the cooler readings expected to be in the Bluegrass and
southern Indiana areas.

&&

.LONG TERM /SATURDAY THROUGH THURSDAY/...
Issued at 306 AM EST Fri Nov 8 2024

Saturday - Sunday night...

Progressive shortwave ridging will initially be in place over the
Ohio Valley Saturday morning. A closed low is forecast to be
spinning over the CO/KS High Plains. High pressure at the sfc and
aloft quickly shifts east of the region as low pressure lifts
northeast across the central Plains. Southerly WAA and moisture
transport into the region increase, especially during the second
half of the day. However, lingering dry air in the low to mid-levels
will keep the vast majority of the CWA dry into the afternoon hours.
Look for a relatively dry Saturday, with increasing clouds and highs
in the mid 60s to near 70.

As the wave ejects northeast over the Midwest Saturday night,
favorable jet dynamics and deep moisture will overspread the Ohio
Valley. Still expect a period of fairly widespread moderate rain
Saturday night through Sunday. PW values are forecast to reach 1.5-
1.6 inches, which is near the BNA Max Moving Average for this time
of year. ECMWF Extreme Forecast Index (EFI) for QPF is around 0.7
for the Sat night-Sun time frame, increasing forecast confidence in
an unusually rainy episode. Rainfall amounts of 1.0-1.5 inches still
look likely for most, though could see 1.5+ inch totals in south-
central KY.

Forecast soundings continue to show a fairly stable environment
Saturday night and Sunday, especially in the lower levels. The risk
for severe weather is low, though Sunday will be a bit breezy. There
is a slight risk for thunder on Sunday. Lows will be in the 50s,
with highs in the mid/upper 60s.

The cold front is forecast to sweep through late Sunday, with
conditions drying out from NW to SE Sunday night. Lows Monday
morning should range from the low/mid 40s in southern IN to the
low 50s near Lake Cumberland.

Monday - Thursday...

The weather looks pleasant and dry early next week with high
pressure building east across the Ohio Valley and Great Lakes. Highs
in the low to mid 60s will be common, with morning lows in the upper
30s to mid 40s.

Another storm system organizing over the central part of the country
will likely bring us additional rainfall Wednesday into Thursday.
However, there remains quite a bit of spread in the evolution of key
synoptic features. Some deterministic model runs feature quite a
deep and dynamic low pressure system, but forecast confidence in the
details remains low. Thus, both SPC and the CSU ML forecasts do not
highlight any meaningful severe weather probabilities at this time.

&&

.AVIATION /18Z TAFS THROUGH 00Z SUNDAY/...
Issued at 1211 PM EST Fri Nov 8 2024

VFR conditions will continue through the current TAF period. Dry air
moving further south into the area have eroded the MVFR cloud layer
that was present early this morning over BWG and RGA. For the next
24 hours, only upper clouds will stream from the west while surface
winds shift from the north-northeast to the east by tomorrow morning
thanks to high pressure traveling across the Great Lakes.

&&

.LMK WATCHES/WARNINGS/ADVISORIES...
KY...None.
IN...None.

&&

$$

UPDATE...ALL
SHORT TERM...CJP
LONG TERM...EBW
AVIATION...ALL