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Area forecast discussion 
National Weather Service Louisville Kentucky
638 PM EST Monday Nov 30 2015

..forecast update...
Issued at 636 PM EST Mon Nov 30 2015

Scattered showers have developed this evening across southern in and
central Kentucky. The more widespread area of rain is beginning to move
into south central Kentucky. Guidance shows this first batch moving
northeast, mainly across central Kentucky through the late evening to
early overnight hours. There then looks to be another round moving
in from the southwest after around 08-09z. Again the most widespread
precipitation should be across central KY, but will still keep
around a 60% chance of rain across southern in overnight. In
addition, some patchy fog has been reported this afternoon and
evening across the region. Any fog chances should retreat to the
north tonight as the warm front moves north across the area. Made
some edits to the pop grids based on current radar trends and latest
model guidance.

Short term (now through Tuesday night)...
issued at 315 PM EST Mon Nov 30 2015

Difluent flow aloft has not yet provided enough lift for rains
across our region this afternoon, though do have plenty of low
clouds and even some drizzle out there. Still expecting coverage to
pick up later this evening, with categorical pops over most of the
area. The best rainfall totals still look to be over Our Lake
Cumberland counties, with totals ranging from 1-2 inches by Tuesday
evening. Rain probabilities are high over the Louisville area, but
totals look more in the quarter- to half-inch range.

Temperatures will not change by more than a few degrees the rest of
the afternoon and should hold steady this evening before starting to
rise after midnight, mainly along and east of a ksdf/kbwg line, as
southwest winds bring in warmer air. Have had some reports of fog,
and cannot rule out additional fog this evening as that moisture
advects into the area.

Highs Tuesday may come in the morning hours, as a cold front coming
through will steady or bring falling temperatures through the
afternoon...along with drier conditions.

Will hold onto lower chances for rain in the east Tuesday night as
the better moisture lingers a bit longer there, but region should be
dry by daybreak Wednesday.

Long term (wednesday through monday)...
issued at 315 PM EST Mon Nov 30 2015

Broad upper low looks to Cross Lake Michigan during the day
Wednesday. Models try to spit out some light quantitative precipitation forecast as the trough axis
crosses US Wednesday night, but moisture in soundings looks too deep
and too warm at the top of the saturated layer to have anything more
than light sprinkles or perhaps drizzle with this system. Left in
the previous forecast for chance of sprinkles mainly north of the I-
64 corridor.

Weather should be quiet Thursday through the weekend, as the next
system the models show crossing our region holds off until Monday
or Monday night. Canadian holds the system more to our southeast,
with some weak deformation ahead of a trailing upper low. Blended
model solution came up with slight chances for Sunday night but
kept US dry, instead opting to bring in the rain closer to
deterministic solution blend timing of Monday.

Temperatures don't stray too far one way or another from normal
through the period.


Aviation (00z taf update)...
updated at 547 PM EST Mon Nov 30 2015

Low ceilings and visibilities will continue to be an issue tonight
into tomorrow morning as a warm front lifts north across the area.
Ceilings are LIFR and Lex and sdf and are expected to remain in this
category through the night as more moisture streams into the area.
Bwg has temporarily improved to IFR/marginal MVFR with the onset of
rain, but is expected to lower again over the next few hours. There
is a chance that ceilings could drop to below airfield minimums
briefly overnight, through guidance only hints at this for a very
brief period. With the rain moving in overnight, this generally
lifts ceilings a bit so have opted to keep all the taf ceilings at
200 feet or above overnight. Visibilities will generally be in the 1
to 3 mile range, but could bounce around depending on the rain
moving through.

A cold front will move through tomorrow. Winds will shift to
westerly in the wake of the front. Ceilings will also start to
improve by late morning to early afternoon. Sdf could see VFR
conditions by late tomorrow afternoon followed by bwg and Lex by
early evening.


Lmk watches/warnings/advisories...


short term.....Rjs
long term......rjs

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