Area Forecast Discussion
Issued by NWS Louisville, KY
FXUS63 KLMK 191951
Area Forecast Discussion
National Weather Service Louisville KY
351 PM EDT Wed Apr 19 2017
.Short Term...(This evening through Thursday night)
Issued at 315 PM EDT Wed Apr 19 2017
Isolated to scattered showers and storms will continue through this
evening in a warm, unstable environment with weak sfc boundaries.
Well removed from any major forcing mechanisms, any t-storms should
be below severe limits. At best a t-storm may contain heavy
rainfall and gusty winds. Convection will diminish after sunset
this evening from NW to SE. Expect a dry period overnight tonight
with lows in the lower 60s.
For Thursday, a cold front will approach the area late in the day.
Ahead of the front, expect breezy southwest winds with gusts in the
25-30 mph range Thu afternoon. The morning hours should be mainly
dry with precipitation chances increasing over southern Indiana
during the mid to late afternoon hours.
Clusters of storms along and just ahead of the cold front will enter
our region Thu evening and move ESE through the area Thu night.
Around 25-30 kts deep layer shear and around 1000 J/KG of CAPE
should be enough to support some strong storms Thu evening/night
with gusty winds up to 40-50 mph, small hail, and brief heavy
rainfall. Southern Indiana and north central KY will likely have the
best chance to see any stronger storms before instability really
decreases by late evening for south central/east central KY.
Highs on Thu should reach the lower 80s with lows Thu night ranging
from the lower 50s over S. Indiana to lower 60s over south central
.Long Term...(Friday through Wednesday)
Issued at 340 PM EDT Wed Apr 19 2017
...Unsettled weather to continue through the weekend...
The aforementioned cold front will settle near the KY/TN border for
Fri providing rain chances to mainly south central KY but a 20-30%
chance of rain will still be possible as far north as the Ohio River
and portions of southern IN during the day Fri. Feel that limited
instability will keep t-storm chances confined to south central KY.
The cooler post-frontal airmass will limit highs to the mid 60s to
Friday night rain chances will increase as a strong low pressure
system approaches the Ohio Valley. Lows are expected to range from
the upper 40s to mid 50s.
Saturday confidence is increasing in a cool/rainy day for much of
the area. Expect a couple different rounds of steady rain with
embedded isld-sct t-storms. There is still some uncertainty as to
when the better rounds of precip will pass through our area but even
in between rounds scattered showers look likely. With the sfc low
passing over south central KY or to the south, no severe weather is
anticipated with any storms attm. However, this low pressure track
will also result in cool temps with many locations not making it out
of the upper 50s/low 60s for highs on Sat. Some of the coldest
model guidance suggests highs only in the upper 40s in S. Indiana.
Rains will continue Sat evening and then begin to become lesser in
coverage Sat night after midnight. Lows Sat night should fall into
the mid 40s to around 50.
Sunday - Wednesday...
Rains will linger into Sun morning but finally begin to exit the
area by late morning or early afternoon as the upper low finally
moves east of the region. We`ll enter a dry pattern with a warming
trend behind the weekend weather system. Sunny skies will return
for Monday with temps warming through the 70s/low 80s for the first
portion of the work week.
.Aviation...(18Z TAF Issuance)
Issued at 110 PM EDT Wed Apr 19 2017
Scattered showers will be possible at the front end of the forecast
period for all of the terminals. Coverage will be widely scattered
west of I-65, but will likely be most concentrated in the Bluegrass
region of central KY (affecting KLEX). Expect convection to wane by
early evening with skies going partially clear overnight. It
appears that the boundary layer will stay mixed overnight precluding
fog formation. Thursday will be mostly dry throughout the day with
gusty southwest winds expected. Sustained winds of 10-15kts with
gusts up to 25kts will be possible at times.