Area Forecast Discussion
Issued by NWS Louisville, KY
FXUS63 KLMK 301738
Area Forecast Discussion
National Weather Service Louisville KY
138 PM EDT TUE AUG 30 2016
...Updated Aviation Discussion...
.SHORT TERM (Now through Wednesday)...
Issued at 245 AM EDT Tue Aug 30 2016
Strong upper ridge still parked over the Ohio Valley will keep temps
several degrees above normal to close out the month of August. Ridge
axis is almost directly overhead today, keeping convective temps
above 90F. With the surface pattern providing no real focus for
convection, will carry a dry forecast for today and into tonight.
Synoptic and hi-res models show storms to the northwest trying to
make a run at the area late in the afternoon, but even the WRF-NMM,
which is the most bullish with this activity, shows it dissipating
rapidly over southern Indiana during the early evening. Anything
that does develop will be too isolated to even justify a 20 POP. Max
temps this afternoon will reach the lower 90s with the heat index
again pushing 100, but still well short of advisory criteria.
By early Wednesday an upper trof axis will be diving SE out of the
Upper Midwest, with convection focused behind a cold front. If there
is any surface convergence to be had, it is to our south and east
over the Cumberland Plateau, and with any convective line starting
to break up as it drops into the Ohio Valley, a decent chunk of the
area could miss out again on precip Wednesday. Best chances will be
focused over southern Indiana, where we have high-end chance, but
will taper down to just a slight chance south of the Parkways. By
the time any storms arrive, instability will be decreasing so severe
potential is quite limited.
.LONG TERM (Wednesday Night through Monday)...
Issued at 250 AM EDT Tue Aug 30 2016
Wednesday Night - Saturday
Will hang on to slight chance POPs Wednesday night into Thursday
morning as the long-awaited cold front moves through. The stronger
dewpoint gradient will take its time clearing the area on Thursday,
and there remains enough trofiness aloft to support slight chance
POPs in parts of south-central and east-central Kentucky through
midday Thursday. Dewpoints really start falling Thursday afternoon,
and cold advection on a NE breeze will limit max temps to the lower
Strong high pressure building into the Great Lakes will provide a
pleasantly mild and dry northeast flow through the first half of the
weekend. Temps will run a few degrees below normal by day, and the
low dewpoints will allow quite a few spots to dip into the 50s each
Sunday - Labor Day...
Upper-level ridging builds again from the southwest for the latter
half of the holiday weekend, bringing the return of typical late
summer temperatures and humidity. Temps will recover to just barely
on the high side of climo, and dewpoints will recover into the mid
60s. However, the ridge axis remains far enough to the west to limit
the return flow, so not expecting enough deep moisture nor a focus
for showers/storms, and will keep the forecast dry
.AVIATION (18Z TAF Update)...
Issued at 125 PM EDT Tue Aug 30 2016
VFR TAFs are expected as upper level ridging remains in control of
the region. There is a signal for light fog at BWG in MOS guidance,
but will only go with 6sm br since no rainfall is expected today and
sfc moisture levels were too low for any fog yesterday morning. The
next TAF concern will be tomorrow after 18Z when a cold front brings
showers/storms to the region.