Area Forecast Discussion
Issued by NWS Louisville, KY
FXUS63 KLMK 192314
Area Forecast Discussion
National Weather Service Louisville KY
614 PM EST Thu Jan 19 2017
.Short Term...(This evening through Friday night)
Issued at 315 PM EST Thu Jan 19 2017
Afternoon satellite imagery and observations show plenty of cloud
cover across the region this afternoon. Moisture continues to
stream northward and scattered rain showers continue to move into
the region. Temperatures were generally in the lower to middle 50s.
Rain is expected to increase in coverage later this afternoon as
more moisture pushes northward out of Tennessee. Temperatures will
remain in the lower to middle 50s through the evening hours.
The short term models continue to be in agreement with a mid-level
wave moving northeastward out ahead of a closed Plains upper level
low. The short term models insist that the coverage will increase
across the region late tonight. This seems reasonable as convection
continues to re-develop across southern Arkansas and northern
Louisiana. This will move northeast and pass through the region
later this evening and overnight. Model soundings still show some
very weak elevated instability which may result in a few rumbles of
thunder...mainly over southern KY. Temperatures overnight will
generally remain in the mid 50s overnight..perhaps rising a degree
or two toward morning.
The rains will shift to the northeast early Friday as the upper
trough axis swings into the Great Lakes. Some light precipitation
may linger through the morning and plenty of cloudiness will stay
entrenched across the region during the day. Temperatures will warm
into the lower to middle 60s. Cloudy and dry weather will remain in
place for Friday night with lows in the lower 50s.
Total rainfall in the short term period will average between 1.0-1.5
inches with the most being concentrated down across southern
Kentucky. These amounts are in good agreement with the latest
ensemble runs. This rain, falling on already wet grounds may lead
to some isolated minor hydrologic issues across far southern
.Long Term...(Saturday through Thursday)
Issued at 350 PM EST Thu Jan 19 2017
Saturday through Monday Night...
We`ll remain in a warm, moist southwesterly flow pattern at the
beginning of the forecast period (Saturday). A weak disturbance
will shear out as it passes through the southern part of the
forecast area. This feature will bring a chance of showers and
perhaps a rumble of thunder mainly to our south and southeastern
sections Saturday afternoon and into Sunday. Highs Saturday will be
very mild with readings topping out in the mid to upper 60s with
lows Saturday night dropping in the lower 50s.
By Sunday a potent upper level low will eject out of the western US
and roll through the southern Plains and into the southeastern US.
There remains a bit of spread in the models with the track of this
system. The GFS and Euro take the system mainly to our south while
the SREF ensembles take the system a bit more northward. In all of
the cases, a band of moderate to heavy rain with some embedded
convection will push through the region Sunday afternoon through
Monday with precipitation moving off to the east by Monday night.
There still remains some model spread in the QPF amounts and
placement. The multi-model consensus suggests that mainly southern
KY would be at most risk for picking up the higher amount of
rainfall totals. It should be noted though, that this storm system
will likely produce a severe weather episode across the deep south.
Should this occur, there remains a risk that widespread convection
across the deep south may reduce the amount of moisture up across
the Ohio Valley. So rainfall could be a bit less than what some of
the models are showing.
Highs Sunday will be in the lower 60s with overnight lows in the
lower-middle 40s. Highs look to be a little cooler on Monday with
highs in the upper 40s to the lower 50s. Lows Monday night look to
cool into the middle to upper 30s.
Tuesday through Thursday...
As the strong upper trough heads off to the east, it appears that
we`ll get a little bit of ridging into the region Tuesday and into
Tuesday night as we`ll be in between systems. Temperatures look to
remain mild with highs in the lower 50s and overnight in the lower
40s. The next weather system looks to approach the region on
Wednesday bringing a slight ramp up in temperatures along with a
chance of more rain showers. Temps will spike just ahead of the
system with readings topping out in the mid-upper 50s. After the
frontal passage, temperatures will head back to more seasonal late
Jan normals with highs on Thursday topping out in the lower to mid
Looking ahead, the long term models continue to be in agreement with
a colder pattern developing across the eastern US as a large upper
trough axis becomes established across the eastern US with a larger
ridge building out across the west. This agrees well with the
overall teleconnection patterns with a +PNA pattern and the EPO
falling into the neutral to slightly negative range. Some wintry
weather looks very possible this weekend as a number of weak
disturbances move through the trough axis. The cold pattern looks
to carry us out through the end of January and into February.
.Aviation...(00z TAF Issuance)
Issued at 613 PM EST Thu Jan 19 2017
Cigs/Vis will continue to deteoriate overnight as widespread rain
overtakes the CWA. Generally expect MVFR/IFR Cigs/Vis, but could see
areas of LIFR Cigs/Vis overnight into tomorrow morning. The rain
will end tomorrow morning, from southwest to northeast, as drier
air moves into the region. Should see Cigs/Vis go VFR by the