Area Forecast Discussion
Issued by NWS North Platte, NE

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FXUS63 KLBF 280958

Area Forecast Discussion
National Weather Service North Platte NE
358 AM CST Mon Nov 28 2016

.SHORT TERM...(Today and tonight)
Issued at 349 AM CST Mon Nov 28 2016

The primary sensible weather concern in the short term period are
strong winds developing mid morning persisting through the
afternoon and then light accumulating snow across the extreme
northeast NEB Panhandle and northwestern Sandhills after midnight.
The latter will combine with moderate winds that won`t lessen
overnight as much as the southeastern half of the local forecast
area. As such, a winter weather advisory was issued this package
for western Cherry and Sheridan counties, wherein the greatest
accumulations of 1-4 inches are expected along and north of
Highway 20 from Kilgore to Hay Springs, because of the combination
of snowfall and strong winds. Snow and snowfall amounts, sky
cover, and winds were the main forecast challenges today and

The large scale pattern features a broad 500 hPa trough currently
present over the Western CONUS and Great Plains with a ridge
extending from the central and eastern Gulf coast to the Lower
Great Lakes. Water vapor imagery shows a mid-level disturbance
currently entering the Upper Mississippi Valley with a mid-level
closed low over the Middle Missouri Valley. In addition, strong
cyclogenesis has occurred with a surface low now present over
eastern SD at about 978 mb presently. The aforementioned
disturbance aloft will continue to rotate around and move into
western/central ND by this evening. The 500 hPa closed low will
feature little movement today-tonight over the Northern Plains.
Overnight, it`s anticipated that moisture will wrap around the
circulation as the short wave trough pushes through western and
central SD late tonight. Light snow is expected to develop in the
far northwest quad of the local forecast area (the extreme
northeast NEB Panhandle, Pine Ridge, and extreme northwestern
Sandhills) after midnight. The aforementioned surface low will
see little movement today-tonight as well and fill in to about
985 mb by early tomorrow morning. The low pressure system will
prompt strong winds today across western and north central NEB
today with very good potential for upper levels winds to mix down
to the surface via momentum transfer. Gusts are expected to peak
to 28-35 kts this afternoon based on BUFKIT soundings, strongest
across the eastern NEB Panhandle and the western and central
Sandhills. Winds will lessen some overnight, however, strong
breezes will persist. Cold air has not quite worked it`s way into
western and north central NEB, thus today will see highs near to
slightly above normal.

.LONG TERM...(Tuesday through Sunday)
Issued at 349 AM CST Mon Nov 28 2016

Tuesday through Wednesday Night: In the mid range, snowfall
chances and snow accumulations are the main forecast concern.
Upper level low pressure and an associated surface low will
meander and drift slowly south across eastern South Dakota and
western Minnesota on Tuesday into Wednesday night. Temperatures on
Tuesday will be cold as a cold front will continue to push south
of the area into Kansas. Highs will generally be in the 30s and
will struggle to reach the freezing mark over northern Nebraska.
In addition to much colder temperatures, there will be an
increased threat for snow Tuesday, especially over northern
Nebraska. This is in response to a mid level disturbance, rotating
around the western and southwestern periphery of the low over
eastern South Dakota. Favorable lift in association with this
feature, will increase over far northern Nebraska Tuesday into
Tuesday night. This lift will lead to an increased threat for
light snow during the Tuesday into Tuesday night time frame.
Snowfall will be light however, as the upper level low will be
well occluded, vertically stacked, with a very limited moisture
fetch originating east of the low. At the moment, the greatest
threat for accumulating snow will be over the far northwestern
forecast area, where it will be locally enhanced over the Pine
Ridge given the northwesterly winds. In these areas, based on the
latest blend of model QPF, and incorporating a 13:1 snow to water
ratio, yields snow accumulations from Tuesday morning into
Wednesday morning of 1 to 4 inches along and north of highway 20
in Cherry and Sheridan counties. In addition to snow, a decent
surface pressure gradient will reside from western South Dakota
into western Nebraska. Gusty northerly winds will combine with the
snow, producing an increased blowing snow threat, especially on
Tuesday in the northwestern CWA. After conversing with UNR, it was
decided to issue a winter weather advisory for Sheridan and
western Cherry county-focusing on areas along and north of highway
20 where local enhancement along the Pine Ridge will be the
strongest. The threat for snow will continue into Wednesday
morning as one final vort max on the western side of the low
impacts northern Nebraska before the main system pushes east
Wednesday night.

Thursday through Sunday: The upper level low will push into the
Great Lakes and southern Canada on Thursday into Thursday night.
At the same time, a second low will deepen across the
intermountain west as it dives south into the southwestern CONUS
by the weekend. Further east across the central and northern
plains, a fairly cold airmass will remain in place. H85 temps will
remain stagnant in the -2C to -6C range into Friday, with a slight
warmup noted for Saturday into Sunday. Looking at the mid range
model solutions, they do diverge somewhat with their handling of
the southern system late in the week into the weekend. The EC soln
is much more aggressive with the ejection of this system, forcing
it across the southern plains into the Ozarks by the weekend. The
GFS soln has this feature remaining stationary across the swrn
CONUS into Baja Mexico and actually develops west northwest flow
across the northern plains next weekend. This second scenario
would favor warmer temperatures compared to the EC solution. For
now, have favored a model blend with temps into the weekend with a
gradual warmup back into the 40s to possibly the lower 50s for
Saturday into Sunday.


.AVIATION...(For the 06Z TAFS through 06Z Monday night)
Issued at 1128 PM CST Sun Nov 27 2016

For the KLBF terminal: Expect broken high clouds overnight tonight
through late morning Monday. CIGS will range from 15000 to 25000
FT AGL. Expect few to scattered high clouds for Monday afternoon
and evening. For the KVTN terminal: Expect broken to overcast
skies overnight into Monday morning with CIGS ranging from 10000
to 20000 FT AGL. CIGS will lower to 5000 to 8000 FT AGL Monday
afternoon and persist through Monday evening. Winds will be strong
on Monday with west northwest winds gusting as high as 35 KTS
during the afternoon hours on Monday.


Winter Weather Advisory from 3 AM CST /2 AM MST/ Tuesday to 6 AM
CST /5 AM MST/ Wednesday for NEZ004-094.



LONG TERM...Buttler
AVIATION...Buttler is the U.S. government's official web portal to all federal, state and local government web resources and services.