Area Forecast Discussion
Issued by NWS Louisville, KY
FXUS63 KLMK 230059
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE LOUISVILLE KY
859 PM EDT Tue Jul 22 2014
Issued at 859 PM EDT Tue Jul 22 2014
Forecast remains on track this evening as convection across our
eastern counties has waned. This will lead to mostly clear skies
into the overnight, before some upper level clouds build back in
toward dawn. Did add some patchy fog to the grids, mainly across the
Lake Cumberland region. Don`t expect widespread or dense fog as the
upper level sky cover should build in, and surface winds might stay
just mixy enough (5 mph or less) in many spots.
Did also want to mention that the Air Quality Alert product will
likely be let go soon. Current Air quality index numbers are well
below the Unhealthy for Sensitive Groups range, so the threat should
be over now that the sun is setting.
.SHORT TERM (Now through Wednesday Night)...
Issued at 305 PM EDT Tue Jul 22 2014
Temperatures this afternoon have climbed into the upper 80s to lower
90s with heat indices in the lower to mid 90s. A few light to
moderate shower have popped up along a deformation band stretching
across central Kentucky. A few strikes of lightning may be possible
with the strongest cells with brief heavy downpours. These showers
will dissipate this evening with the overnight period being dry.
Lows tonight will drop only into the lower 70s, with mid 70s in the
Models continue to indicate the cold front will approach the
northern portions of the forecast area by late morning to early
afternoon. Showers and storms will develop ahead of this front
tomorrow morning and spread across the region through the day. These
storms look to be scattered in nature. Chances for severe weather
continue to look small as wind profiles will be rather light.
However, with ample instability and plenty of moisture, a few strong
to marginally severe storms with gusty winds cannot be completely
ruled out. Heavy rain will be the other potential threat with these
storms as PWAT values climb into the 1.8-1.9 inch range. Ponding of
water may develop with any slow moving or training storms. High
temperatures will be tricky tomorrow and depend somewhat on how fast
the precipitation moves in and how much coverage there is. In
general, have gone with highs in the mid 80s across portions of
southern Indiana and upper 80s to lower 90s elsewhere.
Precipitation will be ending tomorrow night with rain chances
shifting eastward as the front moves through. Cooler air will begin
to move in behind the front tomorrow night. Lows will be cooler than
tonight, ranging from the lower to upper 60s from northwest to
.LONG TERM (Thursday through Tuesday)...
Issued at 305 PM EDT Tue Jul 22 2014
Showers/T-storms associated with the aforementioned cold front and
upper level trough should exit the area early Thurs morning.
Cooler, pleasant weather will follow Thurs/Fri as Canadian high
pressure moves south into the area along with an upper level
trough. High temps will be in the upper 70s and lower 80s Thurs/Fri
under mostly sunny skies. Night time lows will be in the 60s.
Flow will become more zonal across the CONUS for Sat before another
upper low dives south into the Midwest for Sun/Mon. This will
result in temps returning closer to normal for Sat...in the upper
80s to around 90 for highs. Then temps will drop below normal
(lower 80s) again for the beginning of next week as another upper
level trough becomes established over the Midwest.
This pattern will continue to bring multiple chances for
showers/t-storms to the region Sat-Tues. The first may arrive in
the form of an MCS Sat in northwest flow. Continued on and off
chances for storms will continue ahead of a cold front progged to
move through some time Monday. These finer details are hard to time
this far out so look for refined forecast POP timing in later
issuances. Tuesday looks dry and cool behind the front.
.AVIATION (00Z TAF Update)...
Issued at 705 PM EDT Tue Jul 22 2014
Expect to see convective trends diminishing in the next couple of
hours as the sun sets. Any lingering showers across eastern KY
closest to LEX will dissipate. This will lead to a mostly clear
night with winds slackening out of the SW to 5 mph or less.
Overnight some MVFR fog may develop at BWG and LEX after 08-09Z.
This should dissipate by mid morning. A cold front will move through
the area tomorrow afternoon, with surface winds veering from
southwesterly to northwesterly as it passes. The front will interact
with an unstable airmass, bringing showers and storms to the area.
Coverage is in question due to the lack of upper level forcing. So,
will include only VCSH in the afternoon/evening hours, however may
eventually have to include some sort of thunder mention.