Area Forecast Discussion
Issued by NWS Louisville, KY

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FXUS63 KLMK 282246

Area Forecast Discussion
National Weather Service Louisville KY
646 PM EDT SAT MAY 28 2016

...Updated Aviation Discussion...

...Forecast Update...
Issued at 540 PM EDT Sat May 28 2016

Continue to have a fairly moist atmosphere in place over the region,
with model precipitable waters in the 1.6-1.8" range, placing us
towards the top of climo for this time of year. That said, all we
have are some light rain showers/sprinkles moving northward across
central KY and southeast IN, with occasional heavier cells
developing and dropping down a lightning strike or two. Outside of
that shield have more isolated to scattered storms. Focus over the
next few hours for storm development will be in our Bluegrass
region, with peak heating occurring there now. Downdraft CAPEs are
much lower than at this time yesterday, so the threat for stronger
wind gusts is lower as well. The current gridded forecast is in
pretty good shape, just adjusted some for current obs and tried to
focus around 00Z to be more in the Bluegrass than other areas.

.SHORT TERM (Now through Monday Night)...
Issued at 236 PM EDT Sat May 28 2016

Isolated to scattered showers with a few lightning strikes have
developed this afternoon. For the remainder of the afternoon into
the early evening, there could be some additional storm development.
Surface based instability has developed, but there is no well
defined trigger for storms. Models continue to try to develop too
much precipitation. So 20-40% pops for this afternoon look fairly
reasonable. No organized severe weather is expected, but isolated
stronger storms with gusty winds and heavy rainfall are not out of
the question. Showers and storms are then expected to wane through
the evening.

Another weak disturbance may lead to isolated shower/storm
development early tomorrow morning across north central KY and
southern IN. However, most location should stay dry through the
morning. From the late afternoon through evening hours, a weak front
will make its way through the lower Ohio Valley. Showers and storms
are expected to develop along this front in the afternoon and
accompany it as it crosses the area.

The front is not expected to bring much cooler air with it, but
Monday will see a slight drop in dewpoints. As high pressure builds
in, these should bring dry weather and clearing skies. The dry
weather looks to last into Monday night.

Temperatures will remain similar the next couple days with highs in
the lower to mid 80s and lows in the 60s.

.LONG TERM (Tuesday through Sunday)...
Issued at 245 PM EDT Sat May 28 2016

The upper level pattern Tuesday and Wednesday is expected to remain
similar featuring a baggy, weak zonal flow with the stronger
shortwaves staying out to the west and north over the Plains states.
This should continue to provide above normal temperatures and
relatively dry conditions across southern Indiana and central
Kentucky. Highs are forecast to top out in the mid/upper 80s with a
mild/muggy morning in the 60s to near 70.

By Thursday through the end of next week, the forecast models are
suggesting that a closed low over the Northern Plains and energy
coming out of the Rockies will form an elongated trough axis and
push it eastward toward the lower Ohio Valley. This feature could
act to funnel better moisture up through the deep South and sweep a
surface front across the area. Given the limited confidence and run
to run variability, will hold the model consensus POPs down to high-
end chance (40 to 50 percent) until guidance agrees on this idea
more. But it`s possible that the latter portions of next week could
be a bit more stormy than in the short term.

Temperatures are still expected to run above late May and early June
normals, especially at night where abundant low-level moisture may
hold readings up around 70.


.AVIATION (00Z TAF Update)...
Issued at 645 PM EDT Sat May 28 2016

A plume of moisture streaming northward out of Tennessee has brought
widely scattered showers to central Kentucky this afternoon. Expect
this to continue through about sunset, or 8 to 9pm EDT. Then this
should give way to mainly high clouds with just a very slight chance
of a shower. A surface front currently located over Missouri will
begin to advance eastward tonight into Sunday. Some of the models
suggest showers may break out ahead of it around sunrise across
north-central Kentucky, impacting SDF, but confidence on this is low
so will hold off mentioning in the TAF for now. Either way, still
expecting VFR conditions.

The aforementioned front should make a sweep across central Kentucky
during the afternoon. A line of showers and isolated thunderstorms
may accompany this, so have introduced VCSH for the afternoon at
SDF/LEX through the end of the current TAF period.


.LMK Watches/Warnings/Advisories...


Short Term.....EER
Long Term......ZT
Aviation.......ZT is the U.S. government's official web portal to all federal, state and local government web resources and services.