Area Forecast Discussion
Issued by NWS Louisville, KY
FXUS63 KLMK 261855
Area Forecast Discussion
National Weather Service Louisville KY
255 PM EDT THU MAY 26 2016
.SHORT TERM (Now through Friday Night)...
Issued at 250 PM EDT Thu May 26 2016
Main forecast concern is convection currently tracking across the
area this afternoon, and chances again tomorrow as we remain in a
more summer-like pattern.
Latest analysis showed upper level ridging over the southeast US
while a trough remained across the central Plains. Impulses lifting
out of Texas northeast toward the lower Great Lakes have sparked
several complexes of showers/storms on the periphery. One line of
storms originated out of Missouri/Illinois and has tracked all day
toward the I-65 corridor.
Dewpoints in the 60s to near 70 combined with brief clearing earlier
today resulted in 2000 to near 3000 J/kg of SBCAPE, especially south
of the KY parkways to the TN border. Shear environment is weak to
modest at best, but just enough to sustain some organization across
The threats likely for our area are marginal severe hail and wind
gust but more likely to be torrential rainfall and potential for
flash flooding. With the slow moving convection, anomalously high
PWATs and convection becoming more west/east oriented, training
cells may pose a flash flood risk around and nearby the Bowling
Green metro area through the evening.
Expect a gradual decrease in coverage and intensity of convection
later this evening, giving way to slight chances for the overnight.
Will have to monitor the potential for fog in the favored areas that
see plenty of rain, especially if clouds clear out. Look for
mild/muggy lows in the 60s to near 70.
For Friday, forecast guidance seems to favor a drier day, especially
along/east of I-65. The best storm activity looks to be further to
the west, so will maintain 10 to 20 percent chances. As a result,
bumped up highs a degree or two and some areas may push 90 if indeed
the area remains dry.
.LONG TERM (Saturday through Thursday)...
Issued at 255 PM EDT Thu May 26 2016
On Saturday, a more pronounced upper level shortwave trough will
swing through the Upper Midwest and lower Great Lakes. The 26.12z
guidance shows impulses passing closer to the area and with the
better dynamics aloft and a continuation of the juicy air mass,
precipitation chances were nudged up in the 50 to 60 percent range.
Still not expecting an all-day washout, but just greater coverage of
showers/storms across the area during the afternoon hours.
Sunday into most of next week the upper level pattern flattens out
across the area and generally there`s a lack of shortwaves moving
through the flow. This may lend toward a drier and warmer period of
weather for the region. Tried to incorporate opportunities for dry
days or nights, but again confidence is limited in this summer-like
The other issue is the evolution and eventual track of a potential
tropical system off the Carolina coast this weekend into early next
week. Whether this acts to suppress convection on the northwest
side, or enhance moisture/convection across our eastern areas is the
Temperatures through the long term will continue to run above normal
with highs in the 80s and lows in the 60s.
.AVIATION (18Z TAF Update)...
Issued at 1245 PM EDT Thu May 26 2016
Well...line of storms from HNB to along the Western KY Parkway
pushing eastward and is the main story of first 12 hours of the
forecast. This moving eastward at 30 to 35 mph. Mesoscale processes
during the afternoon sunshine will allow the storms to maintain
themselves into the SDF area by 1830z.
Scattered storms have developed along old outflow boundaries across
the BWG area, and will have VCTS this afternoon with better
instability in the warm sector.
The HRR takes the precip eastward into the Bluegrass Region around
22z, if in fact it maintains itself. Will be nowcasting LEX TAF.
Surface winds today will be south to southwest around 10 kts with
gusts 10-20 except in storms where gust up to 35 mph are possible.
HNB just had a gust to 36 mph.
Any storms should weaken later this evening with VFR conditions.
However, there could be some light fog developing at BWG and
LEX around daybreak.
Forecast is much drier for Friday with only isolated convection
around the CWA.