Area Forecast Discussion
Issued by NWS Louisville, KY
FXUS63 KLMK 241722
Area Forecast Discussion
National Weather Service Louisville KY
122 PM EDT Mon Apr 24 2017
...Updated Aviation Discussion...
Issued at 101 PM EDT Mon Apr 24 2017
Cloud cover has not really increased all that much this afternoon as
the models have been suggesting. Based on latest GOES-16 data, it
appears that the best chance of clouds will be down across the
southern third of KY where some diurnal cumulus will be seen. With
less clouds, temperatures are running higher than the forecast. Have
made a quick update to the forecast to decrease cloud cover and
increase afternoon highs across the region. Highs in the SE will be
the coolest with readings in the upper 60s. Further north across
north-central KY and southern Indiana, highs in the upper 60s to the
lower 70s will be common.
Issued at 1039 AM EDT Mon Apr 24 2017
Current forecast remains on track this morning. Light precipitation
has diminished across the region. In addition, the low-level cloud
cover has also been eroding nicely with just the Lake Cumberland
region seeing most of the cloudiness this morning. Latest short
term data continues the mostly sunny conditions through the morning
hours. However, the models do suggest stratocumulus re-developing
again this afternoon...mainly in areas east of I-65 and south of the
Ohio River. Current temperature forecasts look OK. However, will
continue to monitor and there may be a possibility that we could
raise temps across S-C KY if cloudiness is less than forecast.
.Short Term (Now through Tuesday)...
Issued at 244 AM EDT Mon Apr 24 2017
Weak ridging will keep the short term dry other than perhaps a stray
sprinkle or two in the Lake Cumberland region early this morning.
Persistent northeast flow and high RH in the 925-850 layer under a
low level inversion and around a circulation centered over Georgia
will keep clouds in the sky today, especially south of the Ohio
River. Clouds are expected to begin to partially break up tonight,
and we should see more sun tomorrow than today.
Sunnier locations, such as from southern Indiana into north central
Kentucky, should see temperatures rise into the lower 70s today.
Cloudier regions will stay in the 60s. With the weak ridging moving
in, the surface pressure gradient will be more relaxed resulting in
lower wind speeds and less gustiness today compared to the past
couple of days. After seasonable lows in the 50s tonight, the spring
sun will take temperatures into the 70s everywhere on Tuesday.
.Long Term (Tuesday Night through Sunday)...
Issued at 257 AM EDT Mon Apr 24 2017
An upper trof will dig into the Plains Tuesday night/Wednesday. A
lead shortwave will eject from the trof and move over the lower Ohio
Valley and into the Great Lakes Thursday. Surface low pressure to
our northwest will swing a cold front through here during the day
Thursday, accompanied by showers and thunderstorms. Although the EC
and GEM are still advertising a quick fropa, the GFS has slowed its
frontal passage down a bit versus previous runs. This slower timing
would increase the chances for strong storms ahead of the front.
Weaker upper waves will pass by Thursday night and Friday,
continuing the chance of scattered showers/storms. Confidence then
increases for more widespread convection Friday night as the GFS,
ECMWF, and GEM generally agree on a surface low organizing over the
Texas Panhandle with a warm front reaching northeast into the Ohio
New energy aloft will dive through the Pacific Northwest and
reinforce the Plains upper trof over the weekend. At the surface the
Texas low will head northeast, lifting its warm front well north of
us. We will be within the warm sector of the storm for the weekend,
then, with highs both days well into the 80s. We can`t completely
rule out the possibility of thunderstorms in the warm, unstable
atmosphere but will keep PoPs low at this point.
.Aviation...(18Z TAF Issuance)
Issued at 115 PM EDT Mon Apr 24 2017
MVFR/IFR strato-cu ongoing across southern portions of the CWA at
this hour. There remains some question as to how far north the
strato-cu will go, as model soundings show SDF under broken to
overcast skies now, but surface observations/satellite reveal
otherwise. With drier air advecting in from the north, will keep
skies mostly clear at SDF this afternoon.
Expect scattered to broken clouds for part of the overnight period,
with southern portions of the CWA hanging on to clouds the longest.
Depending on when the clouds dissipate, could see some fog develop
tomorrow morning in areas that have received a lot of precipitation
over the past few days.