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Area forecast discussion 
National Weather Service Bismarck ND
634 am CST Thursday Feb 11 2016

issued at 629 am CST Thursday Feb 11 2016 changes other than to blend probability of precipitation to radar and webcam
trends through 1230 UTC and the 11 UTC rap/hrrr iterations
thereafter which have a good depiction of the ongoing band of
light to moderate snow across western and south central North


Short term...(today and tonight)
issued at 230 am CST Thursday Feb 11 2016

Light snow today highlights the short term period. Likely to
categorical probability of precipitation west through south central...while lower probability of precipitation
will exist north central into the James River Valley. Snowfall
accumulations of 1 to 2 inches expected across western and south
central North Dakota.

Latest water vapor imagery a shortwave into southeast Alberta
early this morning. Couple jet streaks across northern and eastern
Montana aiding in large scale ascent. Stationary frontal system in
eastern Montana with a surface low pressure sliding along it
today will enhance low level convergence. Surface convergence
combined with the dynamics aloft will produce a widespread area
of light snow...west into south central through middle/late afternoon.
Regional radar shows reflectivitys enhancing and filling in across
eastern Montana and western North Dakota. Higher reflectivitys now
working through north central Montana appears to be the leading
edge of the more organized area of snow.

A chance of snow remains into the evening but the bulk of snow
accumulations will occur during the daylight hours today. The
populated forecast had given a slight chance for light freezing
rain in the far southwest Thursday night. The NAM BUFKIT soundings
show middle level drying at Baker Montana and Lemmon South Dakota
Thursday night. It is possible for light freezing rain to develop
in the supercooled water droplet regime given the amount of Omega
present. Hence concur and will leave that mention in the gridded
forecast for now.

The system departs tonight with a 1046mb in central Saskatchewan
nosing into western and central North Dakota by 12z Friday. Colder
air will be pushed from north to south...with overnight lows ranging
from 10 below zero Turtle Mountains to 20 above southwest.

Long term...(friday through wednesday)
issued at 230 am CST Thursday Feb 11 2016

A cool down Friday into Saturday and potential accumulating snow
Saturday into Sunday morning highlight the extended forecast.

The 00 UTC deterministic suite is in agreement on Arctic high
pressure building across the northern plains Friday...with the
axis slightly westward compared to runs from last night.
However...the core of Arctic air is still forecast to remain east
of the County Warning Area...across eastern North Dakota and into Minnesota
through Saturday. Thereafter...a shortwave coming onshore to the
Pacific northwest Friday night is forecast to propagate east
across the northern plains through the day on Saturday and into
Saturday night. While the 00 UTC suites are in general agreement
on this feature and the potential for accumulating
snow...sufficient differences remain with impacts to sensible
weather...with the 00 UTC GFS having the most amplified wave and
greatest quantitative precipitation forecast. A wintry mix could be possible southwest Saturday
afternoon with low level warm air advection and the possibility
for a warm layer aloft. By early next week...a low amplitude upper
level ridge is favored to build across the western and central
Continental U.S....marking a possible warm up back to above normal


Aviation...(for the 12z tafs through 12z Friday morning)
issued at 629 am CST Thursday Feb 11 2016

Light snow will result in ceilings/visibilities in the IFR/LIFR range at
kisn/kdik/kbis until around 00z Friday. Kmot and kjms will remain on
the eastern fringe of the light snow/precipitation shield...thus
visibilities will remain in the MVFR to VFR category...while ceilings will be
in the MVFR range. Ceilings will return to VFR from north to south
between 00z and 12z Friday.


Bis watches/warnings/advisories...


short term...Kansas
long term...ayd

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