Area Forecast Discussion
Issued by NWS Louisville, KY

Home | Current Version | Previous Version | Graphics & Text | Print | Product List | Glossary On
Versions: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50
601
FXUS63 KLMK 261020
AFDLMK

Area Forecast Discussion
National Weather Service Louisville KY
620 AM EDT Thu Apr 26 2018

...Updated Aviation Discussion...

.Short Term...(Today through Friday)
Issued at 255 AM EDT Thu Apr 26 2018

Sfc high pressure over the Great Lakes continues to push dry low-
level air into the Ohio Valley, with dewpoints ranging from the 30s
over southern Indiana to the lower 50s along the KY/TN border. Low
pressure diving into the southern Plains will become vertically
stacked over the Deep South today, and try to draw moisture
northward into Kentucky. Hi-res models suggest the precip shield
will struggle, remaining suppressed over the Tennessee Valley
through midday, then finally spreading light rain into south-central
Kentucky this afternoon. QPF should be quite light, with less than a
quarter inch in most locations. Along and north of the Western
Kentucky and Bluegrass Parkways we expect the dry air to win out,
and kept the forecast dry. Temps continue below normal, with most
areas reaching the 60s, but coolest temps expected in south-central
KY where rain/clouds will limit warming.

This system should be fairly progressive as a shortwave kicker is
already diving into Wyoming and will eventually move it along.
Northern stream energy swinging through the Great Lakes late Friday
could phase just enough with this impulse to trigger isolated
showers over the Ohio Valley during max heating. Should be even
lighter and lesser coverage than anything today given lackluster
supply of instability and moisture.

.Long Term...(Friday night through Wednesday)
Issued at 255 AM EDT Thu Apr 26 2018

Deep upper trof retreats into the eastern Great Lakes Fri night and
we finally start to see heights increase over the Ohio Valley late
on Saturday. Cyclonic curvature in the flow aloft and hard to time
impulses could support the slightest of chances for precip in this
time frame. Will keep them barely mentionable as 20 POPs and limited
to our northern and eastern Bluegrass counties. Otherwise will just
keep temps on the cool side of climo.

High pressure really starts to exert its influence Saturday night
and will continue into early next week. Sunday morning will be the
coldest of the next 7 days, as clear skies and northerly flow allow
temps to drop into the 30s. Not too concerned about frost yet as
winds will most likely stay up just enough with the sfc high
centered over southern Lake Michigan.

Once that cold morning is out of the way, expect a warming trend
with temps finally recovering above climo by Monday or Tuesday.
Moisture return could drag rain chances back into the picture later
Wednesday as a couple systems start to impinge on the eastern CONUS
ridge.

&&

.Aviation...(12Z TAF Issuance)
Issued at 615 AM EDT Thu Apr 26 2018

Plan on VFR conditions through the period at all TAF sites. A weak
weather system will pass south of the area later today, bringing
scattered showers to BWG, mainly in the mid/late afternoon hours.
Otherwise, winds are expected to be light and skies will feature mid
level cloudiness becoming mostly clear toward the end of the period.

&&

.LMK WATCHES/WARNINGS/ADVISORIES...
IN...None.
KY...None.
&&

$$

Short Term...RAS
Long Term...RAS
Aviation...ZT



USA.gov is the U.S. government's official web portal to all federal, state and local government web resources and services.