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Area forecast discussion 
National Weather Service North Platte NE
654 am CST Sat Feb 13 2016

issued at 353 am CST Sat Feb 13 2016

Arctic high pressure was centered across Minnesota into Iowa with
low pressure extending from central Montana...eastern Wyoming into nctrl Colorado. A
pressure gradient was present across western Nebraska with
prevailing south to southeast winds of 5 to 15 miles per hour. With modified
Arctic air recirculated into the area...temperatures contrasting from
15 at Oneill to 29 at Ogallala and Imperial. Widespread stratus
extended across western Nebraska with some fog and freezing drizzle
reported from the eastern Panhandle and western sandhills into
southwest Nebraska.


Short term...(today and tonight)
issued at 353 am CST Sat Feb 13 2016

The main forecast concerns will be light freezing drizzle continuing
this morning. A call the the Ogallala sheriffs department
with light freezing drizzle causing slick street where untreated.
A current lack of any middle/high cloudiness across the southwestern
half of the forecast area along with a warm front beginning to nudge east to
keep the threat for freezing drizzle this morning. This area
forecast to remain west of an Ainsworth through Broken Bow line. In least a slight chance for light snow east of Highway
83 this morning and across the northeast zones into this afternoon.
Temperatures today will continue to remain cold as modified Arctic
air is recirculated into western Nebraska. Across the eastern
Panhandle and western sandhills...a warm front will advance to just
east of Highway 61. This will allow highs to exceed 40 degrees. Further
east...highs held to the upper 20s to lower 30s. Highs were kept
very near previous highs as MOS guidance in good agreement with forecast
highs. Since the stratus is currently pushed up to the Front Range
of Colorado...mainly overcast skies today.

For tonight...a disturbance currently moving across northern Idaho will
drop southeast into eastern Montana and northestern Wyoming by early this evening.
This will bring a chance for rain or snow to northern Sheridan and
northwest Cherry County...with a chance for snow eastward in north
central Nebraska. While model consensus is for likely probability of precipitation to remain
north of the nebr/South Dakota border...models such as the 06z NAM bring a
piece of this disturbance across nctrl nebr. This scenario could
result in bands of accumulating snow. Forecast is for chance probability of precipitation of
30-40 percent along and north of a Valentine through Ainsworth and
Oneill line. Winds will turn to the west and northwest tonight as a
Pacific front sweeps across. This will cause temperatures to
actually rise during the late evening and overnight hours east of
Highway 83. Early evening temperatures in the upper 20s will rise
into the low to middle 30s...even for counties furthest east such as
Boyd...Holt...Garfield and Wheeler County. Skies will begin to clear
out this evening from the southeastern Panhandle and southwest and into
central areas after midnight.

Long term...(sunday through friday)
issued at 353 am CST Sat Feb 13 2016

A shortwave disturbance and associated Pacific cold front will cross
the region tonight within broad northwest flow aloft. This cold
front will actually bring milder air to the the Arctic air
will be dislodged and replaced with a Pacific airmass in the wake of
the front. High temperatures Sunday will be some 20 degrees warmer
than highs Saturday in places like Oneill and Ewing.

Westerly downslope winds will continue to feed mild Pacific air into
the area for much of the upcoming week. Another in a series of quick
moving shortwave disturbances will cross the area Monday night. Area
sounding profiles indicate any light precipitation associated with
this system will mostly fall in the form of rain...with perhaps some
wet snow mixing in after midnight across eastern portions of north
central Nebraska. At this time amounts look to be very light and
will only carry a 20 or 30 pop.

As mentioned a very mild week in store...with the warmest day likely
to be Thursday. Expect a plume of very mild air aloft to advect
northeast ahead of a strong Pacific cold that will cross the area
Thursday night. H850mb temperatures of 15c to 20c may support highs
near 70 degrees across western Nebraska. Will be conservative at
this point and forecast middle 60s...which is still way above normal
for this time of year.

As mentioned the front crossing the area Thursday night is a Pacific
cold the airmass will remain mild Friday into the weekend
behind the front. One thing will have to monitor with this front is
the potential for high winds Thursday night into Friday. European model (ecmwf)
indicates h850mb winds over 50 kts in the wake of the front...and
appears to be a similar set up to the high wind event we experienced
last weekend.


Aviation...(for the 12z tafs through 12z Sunday morning)
issued at 654 am CST Sat Feb 13 2016

Patchy freezing drizzle will be an aviation concern this morning
across portions of western Nebraska. The freezing drizzle was
mainly confined to portions of the western sandhills including Oga
and tif. In addition..IFR ceilings should gradually improve to mvf
by this afternoon. A disturbance crossing the region tonight may
bring a period of light snow to north central Nebraska including


Lbf watches/warnings/advisories...


short term...roberg
long term...Taylor

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