Area Forecast Discussion
Issued by NWS Louisville, KY

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FXUS63 KLMK 230925

Area Forecast Discussion
National Weather Service Louisville KY
525 AM EDT Fri Jun 23 2017

.Forecast Update...
Issued at 525 AM EDT Fri Jun 23 2017

Radar beginning to light up over our southern Indiana counties. A
look at the big picture too shows a band of increasing activity from
our southwest IN counties down to the MO Bootheel, as per discussion
below. Time-height sections from the RAP shows quite a bit of lift
over Dubois county starting now and peaking in the 15-17Z time
frame. Again, the paired low-level jet is providing convergence and
the upper vortmax providing divergence aloft, inducing the strong
lift in between.

With this update, leaned towards the models handling the current
features the best for pops today through this evening. Areal average
rainfalls from now through tonight run in the 1.5-3" range, again
with the caveat that areal average means you can have some locations
with higher amounts.


.Short Term...(Today through Saturday)
Issued at 215 AM EDT Fri Jun 23 2017

...Remnants of Tropical Storm Cindy Crossing the Region Today...

The center of Cindy is spiraling over central Arkansas this hour. An
upper level closed low is stacked atop this system, with a vortmax
analyzed northeast of the centers, running from near the MO Bootheel
to SW Indiana. Early morning VAD wind profiles indicate a low-level
jet for 40-50 knots running over central KY, with weaker values into
central IN. Convergence along the northern edge of this jet still is
expected to work with the vortmax aloft to generate a narrow band of
heavry downpours in the tropical airmass in place this morning.
Initiation time should run from 9-12Z with heavier rains continuing
well into the morning hours.

As the day continues, a cold front will swoop down from the Midwest
and Cindy will become absorbed as a low along this front. By 21Z,
model consensus places this surface low roughly over far western
Kentucky. Widespread showers and scattered storms will develop in
the warmer airmass ahead of this low. Shear profiles ahead of this
low would argue for some rotating thunderstorms developing in the
afternoon hours, so with low LCLs and some potential for insolation
over southern KY (see clearer skies now over western TN/northern
MS), will have to watch for some isolated quick spinup tornadoes in
addition to the heavy rain threat. Showers should be efficient rain
producers, and we should see areal average rainfall totals in the 1
to 3 inch range today through tonight, with locally higher amounts.

Temperatures today should be held in check into the low 80s, similar
to Thursday. We will see welcome drying and cooler air come in
tonight as the cold front swings by. Lows Saturday morning should be
in the low-mid 60s. The rain should be gone during the day Saturday
with sunshine making a return. Highs will stay below normal though,
around 80.

.Long Term...(Saturday night through Thursday)
Issued at 230 AM EDT Fri Jun 23 2017

Should be mostly dry this period. Continue to see a stronger trough
coming through Monday/Monday night, which a few models squeeze light
rain out of in the north. A little better chance for rain comes
at the end of the period, Thursday, as a cool front may get into
the Midwest. Latest GEM advertises it, but the GFS is dry and the
Euro brings in light rains to the north. Will keep in lower-end
pops given by the blended model. Temperatures should be below
normal most of the period, though it my get to normal levels


.Aviation...(06Z TAF Issuance)
Issued at 1230 AM EDT Fri Jun 23 2017

Regional radars reveal dry conditions across central Kentucky and
southern Indiana at this hour. A band of precipitation in western
Kentucky may clip parts of southern Indiana and north-central
Kentucky later this morning, and could come close to clipping the
SDF terminal. The LEX/BWG terminals should remain dry.

It`s not until late morning and early afternoon that we`ll
see widespread precipitation develop and move into the region.
Expect MVFR cigs/vis with areas of IFR in the heavier showers and
thunderstorms. Drier air will work in from the northwest this
evening and gradually improve cigs/vis.


IN...Flash Flood Watch through late tonight for INZ076>079-083-084-

KY...Flash Flood Watch from 11 AM EDT /10 AM CDT/ this morning
     through Saturday morning for KYZ023>043-045>049-053>057-



Short Term...RJS
Long Term...RJS
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