Area Forecast Discussion
Issued by NWS Louisville, KY
FXUS63 KLMK 261908
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE LOUISVILLE KY
308 PM EDT Sun Jul 26 2015
.SHORT TERM (Now through Monday Night)...
Issued at 304 PM EDT Sun Jul 26 2015
Given a weak cool front dropping in from the north, an outflow
boundary from old convection coming in from the west, and a weak
upper shortwave trof sliding across Illinois and Indiana, will need
to retain small PoPs in the forecast this evening. HRRR has been
doing fairly well with the convection thus far today and supports
small PoPs as well. Convection chances will decrease during the
overnight hours, with another muggy, still night in store. Guidance
has been too warm with both highs and lows lately, so took lows to
around 70 tonight. If we retain more cloud cover than currently
expected, though, that forecast may indeed be too cool.
On Monday what little is left of tonight`s cool front may still be
lingering around the area, and outflow boundaries from overnight
convection to our northwest may be present as well. Precipitable
water values will pool around two inches and the low levels will
become unstable enough to support convection. Mid-level lapse rates,
though, will be quite weak and 7H temps will be warm. With the
absence of a strong trigger and with the upper ridge building in,
will keep PoPs low. High temps will be in the upper 80s to lower 90s.
Any convection tomorrow will be diurnal and should dissipate with
the setting of the sun, so will go dry for Monday night with warm,
muggy conditions once again.
.LONG TERM (Tuesday through Sunday)...
Issued at 300 PM EDT Sun Jul 26 2015
Tuesday - Thursday...
For mid week, we`ll be on the edge of an upper level ridge with a
weak cold front progged to push southeast through the region late
Wed/Wed night. Ahead of the front, scattered storms will be
possible on Tues and Wed. Generally wind profiles look pretty weak
although ample instability exists both days. For Tues, some mid
level capping may help inhibit storm strength and coverage. Storms
that do get going should be mainly heavy rainers with precipitable
water amounts (PWATs) around or just over 2 inches and slow storm
motions. Wed there will be slightly stronger winds and faster storm
motions with high PWATs, so hopefully any heavy rainers will have
some motion to them. Thursday some lingering showers and storms may
occur early in the day over south central KY close to the front.
Temperatures will be in the upper 80s to lower 90s for highs
Tues-Thurs with the hottest day being Wed ahead of the front.
Friday - Sunday...
A dry end to the week looks likely behind the fropa with humidity
values dropping as well. Highs will fall back into the mid 80s to
.AVIATION (18Z TAF Update)...
Updated 109 PM EDT Sun Jul 26 2015
SDF stands the best chance at receiving TSRA this afternoon/evening
as a weak cool front drops down from the north and an outflow
boundary coming in from the west sparks scattered convection. A few
TSRA could affect BWG as well from that outflow boundary as it sinks
to the southeast. Will keep LEX dry for now.
Tonight should be quiet with scattered clouds and nearly calm winds
once again. Could see some BR around dawn, especially at BWG, but
more cloud cover tonight than the past couple of nights may help it
from becoming dense.