Area Forecast Discussion
Issued by NWS Louisville, KY
FXUS63 KLMK 280501
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE LOUISVILLE KY
101 AM EDT Tue Apr 28 2015
...Updated Aviation Discussion...
Updated 850 PM EDT Mon Apr 27 2015
Forecast low temperatures look good, based on current trends. Had
some cloud cover over the region, but with loss of heating those
clouds are fading. Wind is staying up a bit more than last night
though, and that should help to limit the coverage of frost. Despite
low temperatures in our cold spots in the low-mid 30s yesterday, we
did not receive any frost reports here (not to say it didn`t
happen). With the wind and current forecast lows in the upper 30s
for those cold spots, think coverage of frost, if any, would be
further limited, compared to this morning. Will issue a grid update,
but don`t see a need for a zone update at this point.
.SHORT TERM (Now through Tuesday Night)...
Issued at 255 PM EDT Mon Apr 27 2015
A cool, dry airmass will remain in place through tomorrow. We`ll be
on the south side of sfc high pressure so we should still keep a
5-10 mph sfc wind overnight limiting our cooling potential a
little. Low temps should fall into the mid to upper 30s over the
Bluegrass with upper 30s and lower 40s elsewhere. Some
valley/sheltered locations over the Bluegrass that reach the mid 30s
may see some patchy frost as well. However, don`t think frost will
be widespread or last long enough to cause much of an effect on
For tomorrow expect mid and upper level clouds to slowly increase
ahead of a slow approaching upper low. This low looks to bring a
20-30% chance of rain showers to south central KY late tomorrow
night. High temps for Tues should reach the mid to upper 60s under
mostly sunny to partly cloudy skies. Lows Tues night should range
through the 40s.
.LONG TERM (Wednesday through Monday)...
Issued at 240 PM EDT Mon Apr 27 2015
There will be a few chances for rain in the long term period in
association with a couple of mid level troughs mid week, as well as
a frontal boundary at the end of the weekend. Temperatures will
start off cool for this time of year, but should be above normal by
the end of the forecast period.
The first chance for rain will come Wednesday frame a mid level
trough swinging through the Tennessee Valley. We will be on the
northern edge of the precipitation shield for this system. Rain
should mainly affect south and east central KY. Due to more rain and
clouds, this region will also be slightly cooler on Wednesday with
highs topping out right around 60.
The next trough will drop into the Lower Ohio Valley from the north
through Thursday and continue to the south and east through Friday
morning. The best chance for rain with this system right now looks
to be during the day on Thursday. The latest model guidance
significantly expands the area that stands the chance to see rain,
so went ahead and upped pops accordingly. In addition, soundings
show steepening mid level lapse rates as the mid level low swings
through. Expect that there could be some surface based instability
developing, so have added thunderstorms to the forecast as well.
Precipitation will move out by Friday morning with skies clearing as
high pressure builds in. High temperatures Friday look to be back up
into the upper 60s. Dry conditions should continue through Saturday.
Winds will shift to southerly advecting in warmer air. Highs
Saturday will be in the lower to mid 70s.
By Sunday a frontal boundary looks to stall just to the north of the
forecast area. Scattered showers and thunderstorms will be possible
along this boundary Sunday into Sunday night. With continued warm air
advection, highs look to top out in the mid to upper 70s Sunday.
.AVIATION (06Z TAF Update)...
Updated at 100 AM EDT Tue Apr 28 2015
Low pressure moving by well to our south combined with high pressure
to our northwest will keep north to northeast breezes blowing during
this TAF period, mostly at speeds below 10 knots. Clouds should be
inconsequential, consisting of some widely scattered afternoon cu
and cirrus streaming overhead, especially at BWG.