Area Forecast Discussion
Issued by NWS Louisville, KY

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FXUS63 KLMK 100533
AFDLMK

Area Forecast Discussion
National Weather Service Louisville KY
1233 AM EST WED FEB 10 2016

...Updated Aviation Discussion...

...Forecast Update...
Updated at 852 PM EST Tue Feb 9 2016

Light to at times moderate snow showers continue this evening,
though they have become more scattered in nature. Therefore, pops
were decreased to 50% or less for the remainder of the night. The
latest model runs continue to indicate we could see a slight
increase in snow showers again across east central KY after midnight
as a weak wave moves through the upper trough. Therefore, this area
seems most likely to see any accumulating snow over half an inch.
However, most areas will only see up to an additional few tenths.
Will keep the Winter Weather Advisory going as there will likely
still be some slick spots on roads from this activity. The forecast
was also adjusted to drop hourly temps over the next few hours as
they have dropped off faster than previously forecast.

.SHORT TERM (Now through Wednesday Night)...
Issued at 310 PM EST Tue Feb 9 2016

...Another Round of Snow Showers late this Afternoon/Evening...

Coverage of snow showers is expected to increase over the next few
hours as individual disturbances continue to rotate through the
parent trough. Meanwhile, a few peaks at the sun are occurring and
surface temps are maximizing which is helping to steepen low level
lapse rates. This should also help increase intensity of snow
showers a bit through the afternoon and evening. Overall moisture
continues to be shallow, but with the cold air in place saturation
is still occurring up to the -16 to -18 C range, good enough for
dendritic growth. In addition, snow ratios are between 20 and 25 to
1. So, will continue with scattered to numerous light to briefly
moderate snow showers through the afternoon and evening. This will
allow for anywhere from a dusting up to around an inch through the
overnight. Expect that most spots will be around a half inch or
less, and with only localized areas up around an inch. Seeing some
lower visibilities with upstream snow showers, and would like to see
how things progress over our CWA this afternoon/evening. So, will
leave it as is. Some slick spots are still possible through the
Wednesday morning commute so will keep expiration time the same.

Scattered snow showers should linger into tonight with temperatures
dropping into the teens.

Light snow showers and flurries linger mainly across our east
through Wednesday with very little, if any, additional
accumulations. Temperatures will also struggle, only reaching into
the low and mid 20s.

Data continues to trend weaker and further southwest with the
clipper diving through the NW flow aloft. This is likely due to the
dry air in place that limited moisture will likely have trouble
overcoming. Have painted very low chance pops across our far SW with
a buffer of flurries. Lows will again be in the teens.

.LONG TERM (Thursday through Tuesday)...
Issued at 310 PM EST Tue Feb 9 2016

Thursday - Thursday Night...

Persistent NW flow aloft will dominate our upper pattern during this
time, with surface high pressure also overspreading the region
behind the cold front. Expect dry conditions with partly cloudy
skies trending toward mostly sunny/clear later Thursday. Highs are
expected in the upper 20s to around 30 under plenty of sun on
Thursday, dropping into the mid and upper teens again Thursday night.

Friday - Friday Evening...

Still some disagreement for Friday on the overall amplitude of the
upper trough, and the potential for a clipper to dive into our
region. Overall trend has been weaker with available moisture,
likely due to the very dry airmass in place ahead of it`s arrival.
Will keep chances low across our CWA. If some snow is realized, we
would have high snow ratios to work with, so a little QPF would
still yield some very light accums.

Friday Night - Sunday...

Dry NW flow aloft should continue through the weekend, with arctic
surface high dropping into our region. Lows will be in the teens by
Saturday morning, with highs only in the low and mid 20s on Saturday
afternoon. Lows then dip into the upper single digits and low teens
by Sunday morning. Temps will try to recover on Sunday, however are
not expected to get above freezing. This cold air in place will then
set the stage for a potential early week winter event.

Sunday Night - Tuesday...

There is general model agreement in a system moving into our region
as early as Sunday evening lasting through Monday. Details in exact
timing/strength will still need to be resolved, but there is cold
air in place ahead of the storm, and deep moisture to work with. At
this point data would support an all snow event at least across the
northern portions of our CWA until Monday afternoon when perhaps
some warmer air would work into the system and provide a mix of
rain/snow. Will hold off on more details than that until things
become more clear in the coming days.

&&

.AVIATION (06Z TAF Update)...
Updated at 1230 AM EST Wed Feb 10 2016

Scattered to numerous light to moderate snow showers will continue
this morning. While prevailing conditions will be VFR, visibilities
will occasionally be reduced to MVFR or even occasionally IFR. Will
include tempo groups for MVFR reduction in snow showers at all TAF
sites before 12Z.  After sunrise we`ll start to see snow shower
activity slowly move eastward out of the region.  By mid to late
afternoon only a few linger flurries will be left.  Will continue
prevailing VFR conditions throughout the TAF period. Westerly winds
of 8-12 kts will decrease this evening.

&&

.LMK Watches/Warnings/Advisories...
KY...Winter Weather Advisory until 10 AM EST /9 AM CST/ this morning
     for KYZ023>043-045>049-053>057-061>067-070>078-081-082.

IN...Winter Weather Advisory until 10 AM EST /9 AM CST/ this morning
     for INZ076>079-083-084-089>092.

&&

$$

Update.........EER
Short Term.....BJS
Long Term......BJS
Aviation.......AMS


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