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FXUS63 KLMK 141926

Area Forecast Discussion
National Weather Service Louisville KY
326 PM EDT Mon Oct 14 2019

.Short Term...(This evening through Tuesday)
Issued at 250 PM EDT Mon Oct 14 2019

A large area of surface high pressure covers all of Indiana and 
Kentucky. At 500mb above the CWA, zonal flow streams overhead 
pushing the surface system east. As the surface high moves east, 
winds back from west to south as we transition from this afternoon 
through tomorrow.

An upper low pressure system, currently over Saskatchewan, Canada, 
will slide southeast towards the Great Lakes. It will become stacked 
with a surface low with a trailing cold front, and by tomorrow 
evening cause prefrontal clouds and rain chances to move through 
southwest Indiana and central Kentucky.

Tonight's lows under clear skies will drop in to the 40s. Tomorrow's 
highs, driven by warm air advection and clear skies early in the 
day, will reach into the 70s.


.Long Term...(Tuesday night through Monday)
Issued at 315 PM EDT Mon Oct 14 2019

Tuesday Night - Wednesday...

A shortwave trough and associated surface low will move through the 
Great Lakes region Tuesday night through Wednesday, dragging a 
trailing cold front through our region. A brief period of deeper 
moisture combined with forcing from a strong mid and upper level jet 
will help to create numerous showers, and perhaps a few t-storms 
Tuesday night into Wednesday. SREF probs and forecast soundings seem 
to indicate that most potential for instability will be north and 
west of our CWA, with only some meager elevated instability left 
over by the time precipitation occurs. So, will leave a small chance 
for thunder given potential for meager MUCAPE values and the 
available forcing, but this should mainly be a light rain event. 
Overall, QPF continues to range in the .15" to .25" range, but 
precipitation should be fairly widespread.

Precipitation ends from W to E through the day on Wednesday, with 
gusty and cool NW winds behind the front. Highs on Wednesday likely 
struggle in the mid to upper 50s.

Wednesday Night - Saturday...

Strong surface high pressure and upper ridging will slowly slide 
through the area late week through the first part of the weekend. 
Cool temperatures will gradually moderate through this time period, 
with otherwise dry and mostly clear skies. Wednesday night and 
Thursday nights will be the coldest with most lows ranging in the 35 
to 41 degree range, along with frost potential. Lows trend a little 
milder in the 40s by Friday night as high pressure is east of the 
area and a light SW surface flow returns.

Highs will be below normal on Thursday, only topping out in the 
upper 50s and low 60s. Then, temps will moderate as highs reach the 
mid and upper 60s on Friday, and low to mid 70s by Saturday on the 
steady SW flow.

Saturday Night - Monday...

Broad and deep SW flow will dominate over our region to end the 
weekend, gradually amplifying as a trough digs into the central 
CONUS. As this occurs, shower and storm chances will likely return 
to end the weekend and start the new work week as deeper moisture 
and increasing lift ahead of the trough occurs.


.Aviation...(18Z TAF Issuance)
Issued at 135 PM EDT Mon Oct 14 2019

VFR conditions will last through the forecast period. Clear skies 
and light winds will continue until tomorrow evening's cold front 
brings cloud cover and rain to the area.




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