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FXUS63 KLMK 220653

Area Forecast Discussion
National Weather Service Louisville KY
253 AM EDT Tue Oct 22 2019

.Short Term...(Today and tonight)
Updated at 254 AM EDT Tue Oct 22 2019

The bulk of the light rain has pushed east of the CWA, however a few 
lingering showers will persist along the I-75 corridor through the 
pre-dawn hours. Will continue the small chance mention of a 
measurable shower during this time.

Otherwise, expect a dry day with the main weather focus being the 
winds. SW and WSW winds will be steady between 10-20 mph with gusts 
up around 25 mph. A few of the stronger gusts may reach 30 mph this 
afternoon. Skies will be mostly sunny however temps will likely only 
reach the low to mid 60s for highs given the cool advection. Winds 
will slacken this evening into the overnight as surface high 
pressure begins to build into the region from the SW. This should 
allow for temps to drop off into the upper 30s in the cooler spots 
and the low 40s elsewhere. Patchy frost can't be ruled out in a few 
spots, however the light wind component may be a limiting factor.


.Long Term...(Wednesday through Monday)
Issued at 245 AM EDT Tue Oct 22 2019

Very broad troughing aloft will reside across much of the nation Wed 
(almost zonal flow), with W to SW flow aloft across the OH Valley. 
Surface high pressure centered over the southeastern U.S. will allow 
a S to SW low-level flow to develop over our area with dry weather 
and seasonal high temps in the mid and upper 60s. Dry and mild 
weather will continue Thu with afternoon highs mainly in the upper 
60s and lower 70s.

By late week, shortwave energy aloft is expected to dig SE across 
the northern Rockies, which will effectively sharpen up the broad 
trough over the central U.S. This is where the 00 UTC deterministic 
models continue to advertise significantly different solutions which 
results from the track and strength of the shortwave. Solutions 
range from a progressive open trough advancing eastward across the 
OH Valley Fri and Sat, to a much slower closed low forming across 
the southwestern U.S. on Fri/Sat then lifting NE across the central 
U.S. and OH Valley Sun. Either solution would bring showers to the 
OH Valley but during a different time period, with rainfall coverage 
and amounts still to be determined.

The latest model blend, which includes many models and ensembles 
(much more than a few deterministic models), leans toward the slower 
solution with the best rain chances on Sat night and Sun. 
Probabilities at this time are only in the "chance" category due to 
varying model solutions, but these probabilities will increase over 
the next few days as better model/ensemble consistency occurs closer 
to this weekend. Weather conditions early next week will be 
predicated on how this weekend's system evolves.


.Aviation...(06Z TAF Issuance)
Issued at 127 AM EDT Tue Oct 22 2019

Light rain has mainly pushed east of the TAF sites at this hour with 
steady SW winds occasionally gusting up around 20 mph. Still some 
opportunities for brief periods of MVFR ceilings around 2 K feet 
overnight, especially at LEX. Otherwise, expect VFR conditions to 
prevail for most of the daylight hours later today with WSW winds 
between 10 to 20 mph, and occasional gusts up around 25 to 30 mph.




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