Area Forecast Discussion
Issued by NWS Louisville, KY
FXUS63 KLMK 270145
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE LOUISVILLE KY
945 PM EDT Sun Jul 26 2015
Issued at 945 PM EDT Sun Jul 26 2015
Weak cool front is expected to drop into the region overnight.
Scattered thunderstorms have recently increased in coverage to our
north and these will drift south and east into southern Indiana over
the next few hours. For this forecast update, we did increase PoP
chances across southern Indiana and northern Kentucky for the early
overnight period. Rest of the forecast elements look OK at this
.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 (00Z TAF Update)...
Updated 705 PM EDT Sun Jul 26 2015
Weak cool front, outflow boundaries and associated TSRA have
remained well north of the TAF sites so far this evening and with
the loss of daytime heating, expecting a dry evening and overnight
as well. Couldn`t rule a stray shower popping up around SDF but
coverage and confidence is rather low to include.
Expect some light fog again at BWG during the pre-dawn hours tomorrow,
similar to the past few mornings. Otherwise, plan on VFR conditions
again for Monday at all sites. A pop up shower or storm is possible
during the afternoon/evening hours across the region though the
weather conditions aren`t favorable for widespread activity so will
leave a mention out of the TAF.