Area Forecast Discussion
Issued by NWS Louisville, KY
FXUS63 KLMK 292314
Area Forecast Discussion
National Weather Service Louisville KY
714 PM EDT SUN MAY 29 2016
Issued at 700 PM EDT Sun May 29 2016
Daytime heating generated 2000-25000 J/kg of SBCAPE earlier with
healthy amounts of DCAPE as well. So, as convection fired up along
a couple surface fronts and outflow boundaries, a few pulse strong
storms tracked across southwest Indiana and portions of central
Kentucky. Now that daytime heating is waning, storms have
collapsed with a remarkable drop in lightning and cloud top
cooling. As a result, think the overall coverage and intensity of
storms for the remainder of the evening will be isolated to
scattered at best. Have tweaked POPs for the next few hours. The
surface front will work eastward slowly across the area this
evening, washing out overnight across south-central Kentucky.
.SHORT TERM (Now through Monday Night)...
Issued at 245 PM EDT Sun May 29 2016
It`s warm and humid out there this afternoon with temperatures in
the mid 80s and dewpoints in the mid 60s. The concern for the
remainder of the afternoon will be thunderstorms. Storms have begun
to develop along a weak front moving across southeast IL and central
IN. The region has become relatively unstable with 1000-2000 J/kg of
surface based CAPE. However, wind shear remains weak. Precipitable
water values have decreased during the day, but are still 1.2-1.3
inches. All in all, organized severe weather is not expected.
However, a few storms could become strong. Gusty winds and very
heavy downpours would be the main concern. Storms are expected to
remain scattered in nature. The best coverage will be this afternoon
along and north of the Ohio River. Think that coverage should
decrease as the front heads east into the evening hours. The rain
should exit east central KY by late evening with the rest of the
overnight hours remaining dry.
Memorial day looks to be warm and dry. Though temperatures will be
similar to today, dewpoints are expected to decrease a few degrees
in the wake of the front. Highs will top out in the mid 80s. Dry
weather will continue Monday night with lows in the lower to mid 60s.
.LONG TERM (Tuesday through Sunday)...
Issued at 257 PM EDT Sun May 29 2016
Upper level ridging and surface high pressure will bring dry weather
for the beginning of the long term period. Tuesday through most of
Wednesday will see mostly sunny to partly cloudy skies. The main
question will be how hot it will get. Some of the guidance suggests
a high of 90 at SDF on Wednesday. However, increasing clouds and
very green vegetation may work against temps getting that high. For
now will go with highs in the mid to upper 80s across the region for
Tuesday and Wednesday. Lows will be in the lower to mid 60s.
Rain chances will be on the increase late Wednesday afternoon into
the nighttime hours as a front approaches and moves into the area.
This front will continue to slowly sink south and east Thursday into
Thursday night. The best shot at showers and storms looks to be
during the day Thursday.
The front looks to stall just south of the KY/TN border on
Friday/Friday night with lingering storm chances across south
central KY. This precipitation should move out by Saturday morning
with a dry start to the weekend. Temperatures Friday and Saturday
will be a bit cooler in the wake of the front. Highs will be in the
mid to upper 70s with lows in the upper 50s to lower 60s.
.AVIATION (12Z TAF Update)...
Issued at 125 PM EDT Sun May 29 2016
Cumulus clouds around 4 kft have developed over central KY north
thru IN, with a modest SW surface wind of 4-8 kt. As a weak cold
front from the Great Lakes through central IL moves southeast this
afternoon and evening, isolated to scattered convective cells should
develop from OH to southern IN and north-central and northern KY.
With weak forcing but unstable air, coverage should be limited but
any storm could cause brief, isolated wind gusts around 30 kts. SDF
appears to have the best chance given the timing of the front and
best instability, although even here, coverage should be limited and
no more than VCTS. At LEX, any cells may wait til a bit later as
cells begin to weaken, so will carry VCSH for now. Looks like any
activity should remain north and east of BWG. Nevertheless,
conditions will remain VFR except briefly lower in any storm.
For tonight, winds become light NW at SDF and eventually LEX and
light and variable at BWG. By early Tuesday morning, there will
still be residual surface-based moisture as dewpoints remain up.
Thus, at least tempo MVFR fog is possible at BWG and LEX. Conditions
become VFR quickly thereafter on Tuesday with a NNW breeze 5-10 kts.