Area Forecast Discussion
Issued by NWS Louisville, KY
FXUS63 KLMK 021328
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE LOUISVILLE KY
928 AM EDT Sat May 2 2015
Updated 925 AM EDT Sat May 2 2015
Have some high clouds working through the region at this time.
Forecast soundings show a lower base possible this afternoon, in the
6-8 kft range. High-res models have some small specks in the
composite reflectivity fields with these clouds. However dry air
underneath it should limit anything that comes out of them to virga
or a few sprinkles at most. Otherwise temperatures look on track for
a near normal day. No changes are needed to the zone forecast.
.SHORT TERM (Now through Sunday)...
Issued at 251 AM EDT Sat May 2 2015
An early morning analysis revealed surface high pressure extending
from the southern Great Lakes south to the Gulf Coast. Aloft, water
vapor imagery overlaid with 500 mb heights featured a weak shortwave
trough spilling high clouds across the lower Ohio Valley. Winds at
the surface were light/variable with early morning readings in the
For today, plan on dry weather, seasonable temperatures and mostly
to partly sunny skies. Overall, a very pleasant spring day for the
region. Readings will top out in the lower to middle 70s. Morning
high clouds will give way to few to scattered cumulus by afternoon
and with high pressure remaining in control, look for winds to
remain light and out of the west/southwest.
Temperatures this evening will slowly fall into the 60s before
bottoming out in the low 50s tonight. Another dry night is in store
and look for skies to vary from mostly to partly clear as more high
clouds stream overhead.
By Sunday, heights rise as we begin to feel more southerly to
southwesterly flow. 850 mb temperatures are expected to nudge up
from 7-8C today to around 9-10C Sunday, so highs in the upper 70s to
around 80 are on tap. Another mostly sunny day as well with warm
southwest winds 5 to 10 mph by afternoon.
.LONG TERM (Sunday night through Friday)...
Issued at 300 AM EDT Sat May 2 2015
Monday - Tuesday...
A sfc front will become elongated to our north while upper level
ridging builds over the Ohio Valley early this coming week. Most
models keep us dry both Mon/Tue although the 0Z GFS is spitting out
some light QPF for Tues afternoon on this run. Will opt to keep the
forecast dry for now given the strengthening ridge over our area.
Temps will continue to warm into the coming week with Mon/Tues temps
very similar. Highs in the upper 70s/lower 80s with lows in the
upper 50s/lower 60s.
Wednesday - Thursday...
The upper ridge axis looks to align itself through the Ohio Valley
Wednesday and then slowly shift east Thursday. Given this scenario,
think that Wed will probably be our hottest day with many locations
reaching the 83-86 degree range under mostly sunny to partly cloudy
With the ridge axis beginning to shift east on Thurs, will go ahead
with a 20% POP. Soundings show a better amount of CAPE and less
capping for Thurs. Still if the ridge is stubborn or we lack a
shortwave trigger, conditions could remain dry.
Friday - Saturday...
Long range models indicate the upper ridge will continue to slowly
break down through the end of the week with upper level shortwaves
entering the Ohio Valley resulting in better precipitation chances
especially toward Saturday. Will continue to keep POPs in the
20-30% given the uncertainty of the ridge evolution toward the end
of the week. Temps look to stay above normal through the end of the
.AVIATION (12Z TAF Update)...
Updated at 625 AM EDT Sat May 2 2015
Plan on VFR conditions at SDF/LEX/BWG through the period.
Scattered/broken high clouds will work through the region this
morning, then look for few/scattered cumulus with bases 5-6 kft by
afternoon. Winds will be light/variable this morning then out of
west/southwest 5 kts or less this afternoon.