Area Forecast Discussion
Issued by NWS Louisville, KY
FXUS63 KLMK 312130
Area Forecast Discussion
National Weather Service Louisville KY
530 PM EDT WED AUG 31 2016
Issued at 525 PM EDT Wed Aug 31 2016
Weak impulse noted on water vapor imagery was enough to allow a line
of scattered storms to form across the center of the forecast area.
Weak ridging behind this wave has helped to limit development
farther west and north. Still have some weaker showers in southern
Indiana and forming along the river from earlier outflows, but so
far these are not growing overly tall. DCAPEs are fairly low, thanks
to the moist airmass in place over the region. They are a little
higher along our border with TN, so will be watching for gusty winds
from any storms that move through there.
Other thing to watch for later will be fog potential. Dewpoint
gradient will be slow to get in here, so would not be surprised to
see some areas of fog south of the I-64 corridor. Patches are
possible north of I-64 around midnight, but they should begin to
clear up as drier air builds in.
.SHORT TERM (Now through Thursday Night)...
Issued at 240 PM EDT Wed Aug 31 2016
Scattered convection has formed this afternoon over central KY
courtesy of a shortwave well ahead of the approaching weak sfc front
and upper trough. Another area of convective development has taken
shape over central IN early this afternoon. All of this convection
is expected to slowly drift SE as the trough/sfc boundary approach
tonight. Although instability is decent, there`s not much shear to
work with so would expect most storms to stay below severe levels.
However, a few strong storms with gusty winds up to 45 mph and brief
heavy downpours will be possible through this evening.
While most convection will diminish in coverage late this evening,
models indicate isolated showers/storms may still continue through
Thu morning as the upper trough slowly pushes through the region. By
Thu afternoon all locations should be dry.
Temperatures in the upper trough will be pleasant. Expect highs Thu
in the upper 70s/lower 80s with Thu night lows dipping into the mid
50s to around 60 degrees.
.LONG TERM (Friday through Wednesday)...
Issued at 255 PM EDT Wed Aug 31 2016
...Nice Holiday Weekend Weather...
Friday - Sunday...
The coolest day in the long term period will be Fri courtesy of a
broad upper trough over the region and that cooler air being re-
enforced over the Ohio Valley as Tropical Storm Hermine moves up the
east coast. High temps on Fri will range from the upper 70s to
around 80! We`ll see a gradual warming trend through the weekend
but only into the mid 80s by Sun. Dry weather and plenty of
sunshine is expected this weekend.
Monday - Wednesday...
The heat returns to the region early next week as a strong ridge
builds over the eastern CONUS in response to a downstream trough
over the Rockies. This will result in temps soaring back into the
upper 80s/lower 90s for the first half of the work week. Humidity
levels will jump back up too. Rain chances will be little to none
until about mid week when the ridge starts to flatten.
.AVIATION (18Z TAF Update)...
Issued at 110 PM EDT Wed Aug 31 2016
Showers and thunderstorms associated with a cold front moving
through today have already popped up this afternoon. These will
continue through the afternoon hours, so will continue to carry VCTS
at all TAF sites. These are expected to die down this evening with
just hit or miss showers possible overnight, so will keep the TAFs
Through the overnight hours, low level moisture is expected to
remain in place as the drier air will lag a bit behind the front. A
stratus deck looks to develop behind the front. BWG will likely see
the lowest ceilings as it will be farthest from the dry air and
winds will be the lightest there. IFR ceilings are possible towards
dawn at BWG. Will carry MVFR at LEX, but there is a possibility this
site may drop lower as well. Winds at SDF will likely remain
stronger through the overnight hours, so there is less confidence in
ceilings dropping to MVFR or below. Drier air will quickly push into
SDF and LEX Thursday morning with clouds clearing by mid to late