Area Forecast Discussion
Issued by NWS Louisville, KY
FXUS63 KLMK 251855
Area Forecast Discussion
National Weather Service Louisville KY
255 PM EDT WED MAY 25 2016
.SHORT TERM (Now through Thursday Night)...
Issued at 245 PM EDT Wed May 25 2016
Southwesterly flow over the past 12 to 24 hours has brought an
increase in Gulf moisture to central Kentucky and southern Indiana
characterized by dewpoints now in the low to mid 60s. A few
complexes of showers and storms mainly across southern Illinois and
southwest Kentucky have been slowly drifting east toward central
Kentucky early this afternoon but have been limited in intensity so
far by a less favorable CAPE environment and weak to nearly absent 0-
6 km shear.
For the remainder of this afternoon and the evening, the loosely
organized cluster of storms will drift further east toward the I-65
corridor. This may bring a period of showers and an occasional
rumble of thunder. However, as diurnal heating wanes, there should
be a decrease in coverage and intensity, giving way to mainly
showers and perhaps a thunderstorm. The highest precipitation
chances through midnight were confined to along and west of I-65.
Otherwise, plan a mild night with lows in the 60s. The baggy upper
level flow combined with the more moist environment support a
slight chance of a shower during the overnight.
For Thursday, another limited confidence forecast with a similar
setup as today. Models diverge both in time and place on passing
upper level impulses, so for the most part have continued 20 to 40
percent chances for the day, highest in the afternoon during peak
.LONG TERM (Friday through Wednesday)...
Issued at 250 PM EDT Wed May 25 2016
The main forecast concern in the long term is precipitation chances
as we head into the Memorial Day weekend and early next week.
By Friday, the upper level pattern will amplify more with the ridge
off the southeast US coast building while a negatively titled trough
swings through the central Plains and Upper Midwest. At the surface,
the lower Ohio Valley will likely be in between surface high to the
east and waves of low pressure to the north/northwest.
As weak impulses lift northeastward in the broad southwesterly flow
combined with diurnal heating will support the slight chances of
showers/storms each day though not every day or night will be a
washout. There remains some considerable uncertainty in the timing
of specific waves, so will continue with a broadbrush of chances.
Expect above normal temperatures in the low/mid 80s. Some upper 80s
are possible if cloud and shower coverage is less during the day.
.AVIATION (18Z TAF Update)...
Issued at 1245 PM EDT Wed May 25 2016
Well...this TAF cycle is all about the chances for showers and/or
storms. Cluster of storms has developed over Srn IL/Wrn KY from
larger outflow from larger cluster of storms over the Ozarks. This
activity has maintained the morning stable layer of thick mid deck
of clouds over KY. The new HRR keeps the storms moving eastward and
will at least be SHRA vcnty in SDF after 21z. BWG looks like storms
will get there around 1815-1830z.
In fact the HRR takes all the wrn TN convection and brings it into
western CWA, and this seems realistic. Will keep VCTS through
early evening at BWG.
Our confidence is less at LEX, so will keep dry for now and see how
convection evolves and moves east into lower dew point air and more
VFR ceilings and visibilities are expected through this TAF
period,(except in storms). Winds will be SSW today of 10-18 mph
today and slacken overnight to SSE.