Area Forecast Discussion
Issued by NWS Louisville, KY
FXUS63 KLMK 271350
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE LOUISVILLE KY
950 AM EDT Wed Aug 27 2014
Issued at 945 AM EDT Tue Aug 26 2014
Updated the forecast to remove POPs from this morning as convection
remains well to our north over northern IL/IN along a sfc front.
The latest high-res models are catching on to this and don`t really
develop convection over our region until this afternoon. Thus,
expect a dry morning with isld-sct showers/storms over southern
IN/northern KY this afternoon. High temps still look to reach the
upper 80s and lower 90s today.
.SHORT TERM (Now through Thursday)...
Issued at 315 AM EDT Wed Aug 27 2014
Mostly clear skies were noted across the forecast area this
morning. A wide range of temperatures were noted as some drier and
cooler air has advected in from the east-northeast. Temperatures
ranged from the lower-middle 60s in the Lake Cumberland region to
the middle 70s out across the western sections. Overnight minimums
should be reached in the next few hours.
For today, a well-advertised frontal boundary is forecast to slide
southward. This will happen in response to the mid-level ridge axis
breaking down and flattening out at a bit as a mid-level
perturbation moves to the north of the region. Scattered convection
is expected to develop across Indiana and then drop southward into
northern Kentucky. The short term multi-model consensus still
suggests highest PoP chances across our southern Indiana and
northern Kentucky counties (mainly north of the BG and WK
Parkways). Thus have continued low chance PoPs from the previous
forecast. Afternoon temperatures look to top out in the upper 80s
to the lower 90s.
For tonight and Thursday, expect any convection to rapidly decline
after sunset with the loss of heating. Skies should revert back to
mostly clear skies with lows in the lower 70s in the west with
mid-upper 60s in the eastern areas. We should see more scattered
convection redevelop during the afternoon hours on Thursday as the
Ohio Valley will remain on the periphery of an upper level ridge.
High resolution model simulations suggests that convection will
develop upstream and drop down into the region during the afternoon
hours. Afternoon highs will be similar to Wednesday with highs in
the upper 80s to the lower 90s.
.LONG TERM (Thursday night through Tuesday)...
Issued at 300 AM EDT Wed Aug 27 2014
Persistent upper level ridging across the southeastern CONUS will
shift eastward towards the Atlantic coast during the beginning of
the long term period. A trough will move into the upper Midwest and
across the Great Lakes region through the weekend. Surface high
pressure will slowly drift eastward off the coast with southerly
surface winds persisting through the period.
We will start of the period mostly dry as diurnal storms dissipate
Thursday evening. A warm front will push northward across the
forecast area Friday. This may serve as the focus for a few
afternoon storms, mainly across north central KY and southern IN.
Rain chances will then increase through the weekend as the
aforementioned trough nears the area. The best chance for showers
and storms will be Saturday night through Sunday. With PWAT values
1.7" and above any storm that develops will be capable of very heavy
rainfall. A few stronger storms with gusty winds may be possible as
well. Diurnally driven convection will continue into the first half
of next week. Will therefore carry chances for showers and
thunderstorms through Tuesday.
As for temperatures, highs in the mid 80s to lower 90s will continue
through the period. The coolest day looks to be Sunday as clouds and
precipitation will be most widespread. Temps will then warm up
through Tuesday. Lows will be in the upper 60s to lower 70s.
.AVIATION (12Z TAF Update)...
Issued at 642 AM EDT Wed Aug 27 2014
An upper level ridge axis is forecast to flatten out a bit as a
mid-level wave works in from the northwest. This will allow a front
over northern Indiana to drop southward toward the Ohio River this
afternoon. In general, VFR conditions are expected at the
terminals. The only exception will be some brief periods of
MVFR/IFR visibilities down at KBWG due to some patchy fog. However,
this fog is expected to mix out by 27/13Z. Surface winds today will
be generally light out of the northeast. Convection is expected to
develop across Indiana and then drop south during the day. These
storms may affect KSDF and KLEX by late afternoon.