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Area forecast discussion 
National Weather Service North Platte NE
1227 PM CST Monday Nov 30 2015

issued at 325 am CST Monday Nov 30 2015

At 500 mb large closed low over Wyoming as seen in water vapor. High
pressure to the northwest of this low over Washington Idaho with
ridge into western Canada. Cutoff low approaching the Pacific
northwest. Trough from Hudson Bay low into the northeast Continental U.S..
high pressure over the Gulf and Puerto Rico. At the surface a
cold frontal boundary from Louisiana into the Carolinas. Low
pressure over the Colorado rockies into northern New Mexico.


Short term...(today and tonight)
issued at 325 am CST Monday Nov 30 2015

NAM has good run to run continuity and system is evolving fairly
closely to yesterdays run...just a little farther west. Area of
snow over northeast Colorado expanding and stronger wave moving
echoes to the north northeast across western Kansas with narrow
band from Grant to Ainsworth putting out about an inch per hour.
Evolution looks on track with current forecast. Have expanded
slightly west and kept probability of precipitation definite over the southwest expanding
into north central through the day. Long duration event and will
keep the advisory going. Temperatures cool enough today to keep
everything snow. Gradually ending from the south to the north.
Have kept southwest dry after 01/00z. Winds will be slightly
higher than yesterdays run at 10 to 15 miles per hour with gusts to around
25. Lows tonight around 20 with cloudy skies and light winds.

Long term...(tuesday through sunday)
issued at 325 am CST Monday Nov 30 2015

The slow moving low pressure system will continue to lift across
the plains Tuesday with lingering wrap around light snow to
continue across much of northern Nebraska Tuesday...and maybe as
far south as i80 Tuesday morning. While could see an additional
inch or so across the north Tuesday...will not extend the
advisory as the dry air intrusion may be enough to cut snow to
just flurries and see little if any widespread measurable
Tuesday. Confidence just not there to extend.

The low continues it track to the northeast ending light snow for
all areas Tuesday night. By Wednesday morning temperatures could be on the
cold side with the fresh snow pack and clearing skies. Decided to
stay closer to model guidance blend due to northwest winds at 10
to 15 miles per hour. If winds go calm lows could tank into the single

Weak ridging builds in for middle to late week. The warm surge will
battle cooling effect from a snow pack. Will run temperatures below
guidance for a few days...and will have to monitor overnights for
some ground fog.

Models bring a trough across the 4 corners over the
weekend...however the ec is much deeper with this system compared
to the GFS which is more of an open wave. No change to inherited
model blend which is dry keeping the moisture to the south and
will wait to see how models handle this system once it comes
onshore over the Pacific northwest over the next couple of days and is
better sampled.


Aviation...(for the 18z tafs through 18z Tuesday afternoon)
issued at 1222 PM CST Monday Nov 30 2015

Widespread light snow and MVFR conditions will persist along and
north of Interstate 80 through tonight. Conditions may linger into
Tuesday morning before improving Tuesday afternoon. Winds will
increase from the northwest at 10 to 15 kts this afternoon
through Tuesday.


Lbf watches/warnings/advisories...
Winter Weather Advisory until 6 am CST /5 am MST/ Tuesday for

Winter Weather Advisory until 6 PM CST /5 PM MST/ this evening
for nez069>071.



short term...power
long term...masek

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