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Area forecast discussion 
National Weather Service Bismarck ND
250 PM CST Thursday Dec 25 2014

Short term...(this evening through friday)
issued at 250 PM CST Thursday Dec 25 2014

A relatively quiet short term forecast period is expected with
flurries the primary concern. Regional radar mosaic shows snow
from southwest Minnesota into South Dakota and Wyoming. Across
North Dakota...shallow...weak returns persist with nothing more
than flurries being reported. Short term forecast models suggest
flurries will linger into this evening...but should gradually

Friday will start with mainly dry weather...and even some
sunshine is possible. The next 500 mb wave arrives already Friday
afternoon...but forcing associated with it is weak. The 25.12z Gem
suggests there could be a few flurries in western North Dakota
Friday afternoon...however most model solutions keep it
did not add them into the forecast yet.

Long term...(friday night through thursday)
issued at 250 PM CST Thursday Dec 25 2014

The biggest issue of the long term is the very cold air advancing
into the region. The coldest will be Monday night / Tuesday morning
with temperatures in the teens below zero...winds around 10
miles per hour...and apparent temperatures (wind chills) as low as 35 below.
This would warrant a Wind Chill Advisory for that time period.
Actually...chill advisories will likely be needed Sunday
night...Monday night (coldest)...and Tuesday night. The tough
decision on that will be to Post it for each night...or just keep it
going through one or two of those daytime hours as well. Those
decisions will come as we get closer to and work through the weekend.

With the Canadian middle level low / cold vortex moving out of Manitoba
and into Ontario...Arctic air slides down the back side on a north
flow. It moves into North Dakota Sunday and Sunday night with
limited moisture so nothing more than flurries...except the
southwest where upslope flow may ring out a period of light snow
from Dickinson to Bowman areas. The Heart of the Arctic air is over
the state Tuesday morning.

By Tuesday night warm air advection gets underway...from the
northwest. Temperatures could reach their lows early Tuesday night
and then rise through the night...especially west. Counter to that
will be increasing wind speeds in warm advection that may counter
the rising temperatures enough to still produce wind chills in the
20s below.

Temperatures warm...relatively speaking...Wednesday and New Years
Day before the next cold shot for Friday next week.

As far as snow GOES...again...flurries to a little light snow
Sunday-Sunday night...then warm air advection snows are possible
around the New Years Day Holiday.


Aviation...(for the 18z tafs through 18z Friday afternoon)
issued at 250 PM CST Thursday Dec 25 2014

MVFR ceilings will prevail at the aerodromes this afternoon...with
some potential for brief IFR. A few flurries are possible into
early evening...but visibility restrictions are not anticipated.
Ceilings are expected to improve to VFR from northwest to
southeast later tonight...with the trend continuing into Friday
morning. Winds will be from the northwest...and will decrease in
speed tonight.


Bis watches/warnings/advisories...


long term...jpm

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