Area Forecast Discussion
Issued by NWS Louisville, KY
FXUS63 KLMK 011508
Area Forecast Discussion
National Weather Service Louisville KY
1008 AM EST Thu Dec 1 2016
Issued at 955 AM EST Thu Dec 1 2016
Updated the forecast to adjust high temps and clouds for today based
on the latest trends and high-res data. Increased highs in the
Louisville Metro to upper 40s. Also held onto low clouds over
southern Indiana and north central Kentucky through the morning
.Short Term (Now through Friday)...
Issued at 245 AM EST Thu Dec 1 2016
Batch of low clouds continues to push eastward through the region
this morning. In general, the cloudiness is along and north of the
WK/BG Parkways. It may develop a little more south over the next
few hours. Can`t rule out a sprinkle or two as these clouds roll
through this morning. Best chance of that would be along and north
of the I-64 corridor in IN/KY. Temperatures ranged from the lower
40s under the clouds, with mid-upper 30s across the southern areas
that were generally cloud free. For the remainder of the overnight,
drier air is punching in from the west and the low clouds are
skirting off to the east. Clearing looks to take place around dawn
in areas west of I-65, but cloudiness will linger across northern KY
after sunrise. Lows this morning should bottom out in the middle
30s in most places, a few of the low-lying and typical cool spots
that do clear out may drop to around 30.
High pressure will build in from the west later today resulting in
mostly sunny skies. Temperatures will be colder than normal with
highs generally in the lower 40s along and north of the I-64
corridor. Mid to upper 40s along and south of the WK/BG Parkways
looks likely. The warmest temps will be along the KY/TN border
region. Some mid-high clouds may spread eastward along and just
north of our region later tonight. For now, it looks like we`ll see
mostly clear skies and lows in the lower 30s, with a few upper 20s
in the typical cool spots. Dry weather looks to continue on Friday
with a slight warm up in temperatures. It will be seasonal with
highs in the mid-upper 40s across southern IN and northern KY with
upper 40s to around 50 across southern KY.
.Long Term (Friday Night through Wednesday)...
Issued at 307 AM EST Thu Dec 1 2016
...More Rounds of Rainfall Expected and Turning Sharply Colder by
Friday Night through Sunday Night...
High pressure axis will hold sway for Friday night and low
temperatures will fall into the upper 20s to the lower 30s. Seasonal
temperatures are expected for Saturday, but cloudiness will be on
the increase late in the day. Highs will warm into the 45 to 50
degree range Saturday afternoon.
Latest model data continues to show the upper ridge axis shifting to
the east Saturday night and Sunday. A mid-level short wave trough
will quickly move into the region from the southwest Saturday night.
The feature will draw up some Gulf moisture along with some warmer
air. Clouds will spread into the region Saturday night with light
precipitation working northeastward overnight. Temperatures will
cool into the lower-mid 30s overnight which may result in some mixed
precipitation at onset. Model soundings are slightly warmer than in
previous runs. Current thinking is that a short window of mixed
precipitation is possible mainly north of the Parkways in KY and
into southern Indiana where colder surface temperatures may be
found. Warmer air will surge in after sunrise resulting in rain for
the remainder of the day and into Sunday evening. Highs Sunday will
warm into the lower 40s across southern IN and northern KY mid-upper
40s across southern KY. Lows Sunday night will cool into the lower-
Monday through Thursday...
Latest data suggests stronger upper level low will eject out of the
southwestern US and make a run through the Ohio Valley Monday and
into Tuesday. Moderate to occasionally heavy rainfall will
accompany this system as it moves through the region. QPF amounts
of 1-2 inches look very possible by the time the system rolls east
of the region Tuesday afternoon. Highest rainfall amounts will
likely be across our southern areas...with axis of heaviest rainfall
falling well to our south and southwest. Highs Monday will be in
the mid-upper 40s with highs on Tuesday topping out in the lower-
middle 50s. Overnight lows will generally be in the upper 30s to
the lower 40s.
By mid week, the model guidance is general agreement with a very
strong upper trough moving through the Plains states. This trough
will swing eastward driving a very sharp cold front through the
region near the end of the forecast period. There are some slight
timing differences between the models with the GFS a little faster
than the Euro. The theme with this system is that we`ll see a band
of showers and possibly a few isolated thunderstorms develop along
the front and push through the region. A sharp drop in temperatures
is expected behind the front with highs Thursday likely occurring in
the overnight period with temperatures plummeting some 30-35 degrees
during the afternoon hours. There is a chance that the colder air
may catch the back side of the precipitation and we could see some
light snow before the precipitation ends late Thursday afternoon.
.Aviation (12Z TAF Update)...
Issued at 606 AM EST Thu Dec 1 2016
High pressure advancing from Texas to Tennessee will keep central
Kentucky`s weather quiet through the TAF period. A deck of clouds
will sweep through the region this morning, and scattered clouds are
expected during the daylight hours, but these clouds should
primarily stay low-end VFR.
Winds will be consistently coming in from the WSW ahead of that high
to our south, and could gust to near 20kt this afternoon at SDF/LEX.