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fxus63 kgid 140142 
afdgid

Area forecast discussion
National Weather Service Hastings NE
742 PM CST Fri Dec 13 2019

Update...
issued at 733 PM CST Fri Dec 13 2019

As of 7pm, the back edge of the precipitation was approaching
lbf. Temperatures in the lxn/ear/hde area are still in the upper
30s to near 40 degrees, so snow accumulation likely won't be much
of an issue.

Therefore, forecasted snow amounts were reduced slightly.
Anything more than a dusting seems unlikely. Slick spots are
still possible on any wet roadways due to falling temperatures.

&&

Short term...(this evening through sunday)
issued at 310 PM CST Fri Dec 13 2019

The Central Plains sits under northwest flow aloft with numerous
disturbances moving across the area, it will make for an active
weekend.

This afternoon an upper disturbance is moving southeast across the
High Plains, ahead of it light precipitation has developed in
central/west-central Nebraska. This precipitation began slightly
earlier than earlier anticipated, but is currently in the form of
light rain. As colder air moves in tonight, rain will change over
to snow. Expect this to be quick, as the thermal profiles are all
below freezing, so as the boundary layer cools rain will become
snow.

This snow event will be quick hitting...snowfall is expected in
the 00-06z time period tonight (6pm-midnight). Overall less than
an inch of snowfall accumulation is expected, but the high-res
guidance continues to indicate that there could be some narrow
bands of snow that could produce 1-2 inches of snow. The higher-
res models continue to show the best chance for snow will be
between Lexington and Kearney southeast into The Heart of NC
Kansas. A wide spread shows most snow along and south of I-80 and
along and west of Highway 281.

Weekend:
what we don't know...exact snow amounts and location, there is a
lot of uncertainty in how this system will evolve which includes
where the heaviest snowfall will occur.

What we know...snow is likely across portions of the area, wind
will be light and it will be cold.

Saturday:
cold air will filter into the region throughout the day, skies are
expected to be cloudy and highs in the 20s to low 30s in the
south. A piece of energy will move across the Central Plains
Saturday afternoon/evening which will bring a chance for snowfall
to western and central Nebraska. Light snow with accumulations
generally a trace to 2 inches possible for Nebraska counties. The
models are in fairly good agreement about this potential.

Saturday night-sunday:
the main disturbance will move across the western half of the
country. There is quite a bit of uncertainty as to where
precipitation will develop due to this disturbance. The ec remains
much further to the south for snowfall accumulations vs. The GFS
and NAM. The official forecast trend has been slightly to the
north, but it will be interesting to see how this evolves with the
latest guidance. Its not hard to say that confidence is fairly low
in snowfall totals through this event...at least in where the
highest snowfall totals will occur. Do think and advisory level
snow is possible, especially for areas along and south of the
NE/Kansas border, but potentially further north if a further north
track is eventually determined to be true. The official forecast
currently has a range of 1-5 inches for expected snowfall amounts. As
far as forecast details are concerned, used a 50/50 blend for quantitative precipitation forecast
as wpc was higher than the blended models. Additionally, have
removed all mention of ice to the forecast at this time.

Despite all of that, where it does snow, travel will be impacted.
Stay tuned, expect the snow forecast to change over the next
24-36 hours.

Long term...(monday through friday)
issued at 310 PM CST Fri Dec 13 2019

After the busy weekend, the work week looks to be cold, but dry.
Surface high pressure builds in across the area early in the week
and by mid-week upper level ridging will be moving overhead.
Temperatures are cold for the start of the week and with the
ridging, they are expected to warm. This could all be impacted by
the location and amount of snow, but looks as if 40s are a
potential for the later half of the work week.

&&

Aviation...(for the 00z kgri/kear tafs through 00z saturday)
issued at 505 PM CST Fri Dec 13 2019

Light showers may briefly impact the area this evening, but any
persistent rain or snow should remain southwest of the terminals.
Skies will remain overcast, but ceilings will likely remain VFR
for most of the overnight, possibly only briefly dipping to MVFR
around midnight.

Skies may scatter out at times tomorrow morning and early
afternoon, but more VFR cloud cover will move in from the
northwest during the afternoon.

Lowers ceilings and snow is expected to move in Saturday night,
but this is outside of this taf period.



&&

Gid watches/warnings/advisories...
NE...none.
Kansas...none.
&&

$$

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