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fxus63 klbf 302101 

Area forecast discussion
National Weather Service North Platte NE
401 PM CDT sun Apr 30 2017

issued at 356 PM CDT sun Apr 30 2017

500 mb analysis from this morning had a maturing cyclone
located over northwestern Oklahoma, just east of the Panhandle. As
of midday, this feature had migrated east into south central Kansas
just west of Wichita. Surface low pressure was located just to the
west of Wichita and had been deepening over the past 3 hours. A
broad area of deformation precipitation had developed this afternoon
on the northern and northwestern periphery of the low and was
backing into the forecast area from the east. As it traveled west it
was encountering dry air which led to a well defined back side to
the band of precipitation. As of 2 PM CDT the back edge of this
extended roughly from east of Ainsworth, to North Platte to
Wauneta Nebraska. Just to the east of this cutoff line, moderate
to heavy snow was being reported from Holt County south southwest
into Custer, eastern Lincoln, Hayes and Frontier counties. As of 2
PM CDT, Eustis reported 3-4 inches of snow accumulation while
Broken Bow had around an inch and Callaway had an inch as well.
Taylor in Loup County had around a half an inch. Highway cameras
across the eastern half of the forecast area, along with
observations indicate areas of 1/2 mile visibility which has
periodically fallen to a quarter mile. Snowfall rates were
generally on the order of an inch per hour, however, given that it
is daylight and temperatures are in the 30s, snow has had a hard
time building up any accumulation on the ground. Readings as of 2
PM CDT ranged from the middle 30s in the far eastern forecast
area, to the middle 50s over Sheridan County.


Short term...(this evening through monday)
issued at 356 PM CDT sun Apr 30 2017

Ending of precipitation in
association with the upper level low, as well as snow accumulations
for tonight are the main forecast concerns. Looking at the short
term model solutions, as well as the nam12 from this morning as well
as the off hour rendition of this model, feel fairly confident in
where the back edge of the precipitation field will end up and have
tightened up pops and confined them along and east of a line from
Hayes Center, to Hershey to Ainsworth. Looking at the near term
solutions, deformation band one is expected to begin to decrease in
intensity over the next couple of hours. This band currently extends
from Loup County into eastern Lincoln and Frontier counties. Band
two is expected to set up during the early evening hours across
the northeastern four counties, mainly Garfield, Wheeler and Holt
counties. It is with this secondary band, that I am more concerned
with snowfall accumulations. This is primarily due to timing
which will be more during the evening/nighttime hours. As was
mentioned earlier, even with the 1+ inch an hour snowfall rates,
snow is having a hard time building any appreciable accumulations
this afternoon. The late April sun seems to be hindering this
quite a bit. With this in mind, went ahead and increased snow
accums in the northeastern forecast area this evening. With what I
now have, will keep the Winter Weather Advisory as is for now and
not upgrade. Additionally, winds this evening are not expected to
be as gusty as what is ongoing and this is also leading ME more
toward the advisory vs. A warning. This system will track into
northeastern Nebraska overnight tonight with the threat for snow
ending around sunrise. Storm total snowfall will range from a
dusting along the back edge of the precipitation shield, to 5 to 7
inches in portions of Frontier, 2 to 5 inches in Holt, Garfield
and Wheeler counties and an inch to 5 inches in Custer, Hayes, and
Lincoln counties.

Long term...(monday night through sunday)
issued at 356 PM CDT sun Apr 30 2017

Other than an approaching shortwave and threat for precipitation
Tuesday afternoon into Wednesday morning, the outer periods will
be dry and warm. Highs Monday through Wednesday will be in the
60s, followed by 70s for Thursday through Sunday.


Aviation...(for the 18z tafs through 18z Monday afternoon)
issued at 1237 PM CDT sun Apr 30 2017

Rain and snow will back into the klbf terminal from the east
through mid afternoon. Visbys may fall off to a half a mile if
moderate to heavy snow can materialize. LIFR ceilings are expected
to accompany any snow which falls. Conditions will improve by
early evening with VFR conditions expected after 00z Monday. For
the kvtn terminal, VFR conditions are expected over the next 24


Lbf watches/warnings/advisories...
Winter Weather Advisory until 7 am CDT Monday for nez009-010-

Winter Weather Advisory until 1 am CDT Monday for nez059-070.

Winter Storm Warning until 1 am CDT Monday for nez071.



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