Area Forecast Discussion
Issued by NWS Louisville, KY
FXUS63 KLMK 242309
Area Forecast Discussion
National Weather Service Louisville KY
709 PM EDT SUN APR 24 2016
...Updated Aviation Discussion...
.SHORT TERM (Now through Sunday)...
Issued 255 PM EDT Sun Apr 24 2016
Well...Sunny skies combined with temps climbing through the 70`s and
dewpoints in the mid 40`s are making for a very pleasant spring
This evening will once again be mostly clear with
some very patchy fog at the typical fog prone places like BWG. Low
temps will be 10-15 degrees warmer than last night with a southerly
The combination of high pressure over the Delmarva Peninsula
combined with low pressure over the Badger state will create a SSW
gradient flow and allow SW winds to increase throughout the day.
Expecting winds 10-20 mph with some gusts as high as 30 mph during
the afternoon due to strong mixing. Expect an increase in clouds,
but still about 10-12 degrees above normal and continued the theme
of the last several forecasts of going above guidance with temps in
the low to mid 80`s and picked 86 degrees for Louisville. An
increasing dewpoint in the mid to upper 50`s with the highest in
.LONG TERM (Sunday night through Friday)...
Issued at 300 PM EDT Sun Apr 24 2016
...First dose of high humidity coming to forecast area...
...Unsettled and Stormy Tuesday-Thursday...
Well...synoptic pattern has deep upper trough across Central and southern
Rockies with a series of reinforcing pieces of energy to reestablish
the trough. By Thu the next upper low and trough will set up from
Yosemite NP CA to Joshua Tree NP CA to the Grand Canyon. A couple of
these disturbances will be emanating from mean trough and will be
the focus of the long term period, for several chances for
thunderstorms this week.
Potent warm front will be across the Badger State to the Wolverine
State with a series of MCS disturbances riding over the ridge
southeast along this boundary possibly even a diving outflow
boundary that may get south of IND. Keeping previous forecast going
only POPS across the 2nd tier of SRN counties.
Tuesday and Tuesday Night ...
Overnight convection should be in northern CWA border with approaching
and sagging front which will focus convection from Huntingburg to
Seymour to Madison to the northern Bluegrass Region through much of
the day. Surface dew points rise into the 60-64 range and the
instability will be uptick. Plan on chance pops across the area
with high chance or even likely across northeastern CWA. Best shear
is north of I64 especially across the northwestern CWA. Could be a
few strong storms, but wind fields are not strong enough for
Wednesday and Wednesday Night...
Expect some morning convection and much of hump day will be waiting
for negatively-tilted trough ejects out into the Central Plains. The
surface low will lift out of Medicine Lodge KS and front responsible
for the convection late Tuesday will lift back north as a warm
front. After morning convection will have low pops during the day
before the main deep forcing will move into the region Wednesday
night. Then will ramp up POPS to likely.
Dewpoints will be in the low 60s, LIs will be running in the -4 to
-8 C range. Once again, some strong storms could be possible late
Wednesday as deep-layer shear increases, but as it stands now the
timing looks to be rather unfavorable (nocturnal surface inhibition).
Thursday through Friday...
Main area of forcing and deep-layered moisture should push east of
our area on Thursday. However, surface frontal boundary should still
be to our north and drift southward during the day. Model soundings
show steepening low-level lapse rates as some sunshine provides
diurnal heating. Modest instability combined with low-level
convergence along the front should result in scattered diurnal
convective cells. Any storms should weaken/dissipate Thursday night
as the air mass cools and low-level convergence weakens.
On Friday, we will be in-between weather systems with dry weather,
waiting for the next storm system to take shape over the central and
southern Plains. Expect high temperatures around 80/lower 80s
Thursday and 70s Friday.
Friday night through next weekend...
The next storm system will move northeast into the mid MS Valley
over the weekend, with additional chances for showers and
thunderstorms across the OH Valley. As expected, model timing and
details vary, but there is a clear signal for a significant system
to our west. We could experience multiple rounds of precip, with an
initial warm advection/isentropic lift area of rain and embedded
convection Saturday with more convection later in the weekend.
Periods of heavy rain and a few strong storms are possible.
.AVIATION (00Z TAF Update)...
Updated at 705 PM EDT Sun Apr 24 2016
A mostly VFR TAF period is in store as ridging moves through the
Ohio Valley. The only exception may be a brief period of MVFR fog
at BWG during the pre-dawn hours but chances of that happening look
very slim at this point given the mixey atmosphere. Expect SSW
winds to gust to 18-24kts tomorrow afternoon.