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Area forecast discussion 
National Weather Service Bismarck ND
639 am CST Sat Feb 6 2016

issued at 630 am CST Sat Feb 6 2016

Winds already picking up across the west and are gusting close to
30 miles per hour. Currently on track for strong winds by afternoon. Broad
warm advection showing up with 2 to 4 mb 3 hour pressure falls on
latest rap13 model output over ND. Seven to 8 mb 3hr pressure
rises now in central Montana. Current forecast looks good.


Short term...(today through Sunday afternoon)
issued at 330 am CST Sat Feb 6 2016

Highlights include a High Wind Warning for western and most of
central North Dakota and a Blizzard Warning from near The Turtle
mountains south into the upper James River Valley.

Latest water vapor imagery loop shows our next potent shortwave
located near Omak Washington with strong warm air advection ahead
of it into North Dakota. That will be the theme for the morning
hours into early afternoon...then a transition to cold air
advection will occur around 21z west and into central North
Dakota 00z-06z Sunday. Latest BUFKIT soundings per NAM/GFS show
warning level winds being delayed across Bismarck and Jamestown
until 12z Sunday...then strengthening thereafter and maintaining
warning level wind criteria through the rest of this short term
period. This is when the steepest lapse rates of 8 to 8.5 c/km and
strongest isallobaric forcing emerges. Will likely see Wind
Advisory criteria develop after 06z Sunday due to the initial
surge of cold air advection/isallobaric forcing coming in behind
the cold front. Made minor timing adjustments across the rest of
central North Dakota based upon the same logic as above.
Essentially began the High Wind Warning earlier in north central
North Dakota with this area first in line to feel the strongest
pressure rises and strongest winds. Have upgraded the blizzard
watch to a Blizzard Warning from The Turtle mountains and vicinity
south into the upper James River Valley. Most locations will
receive 1 to 3 inches of snow with localized 4 to 6 inches in The
Turtle mountains. The Baggaley snow model hints at a blizzard and
felt with falling snow interacting with very strong
winds...visibilities will be near zero.

For today prior to the main event...temperatures will be warm with
40s...and lower 50s southwest to portions of south central.
Vertical motion increases throughout the period...thus middle and
high clouds will thicken and lower through the day into tonight. A
slight chance of rain enters the far northwest this afternoon with
chances for rain and snow spreading south Saturday evening before
transitioning to snow after midnight.

The southwest and south central will see little or no precipitation
with this system...just the strong winds. Whereas north and east
will experience the strong winds and snow. The High Wind Warning
trumps the mention of lower visibilities at times in areas of
blowing snow for those areas just outside the Blizzard Warning...and
with much uncertainty remaining on how low visibilities will be
and for what length of time...felt it was best to upgrade to a
High Wind Warning as opposed to a winter headline.

Long term...(sunday night through friday)
issued at 330 am CST Sat Feb 6 2016

Residual blowing snow will remain in place across the east
associated with the string winds and light snow Sunday night. By
Monday the upper low exiting the northern plains will develop
into a longwave trough over the Great Lakes south to the Gulf
Coast with a large h500 ridge over the western Continental U.S. And Canada.
This leaves a strong baroclinic zone over the northern plains
which will pretty much define the extended period with mild air
southwest and cold temperatures east. Northwest flow aloft with
several pertebations will result in some scattered light snow
during the week but no significant accumulations expected.


Aviation...(for the 12z tafs through 12z Sunday morning)
issued at 630 am CST Sat Feb 6 2016

Increasing clouds but remaining VFR through 06z Sunday. After 06z
Sunday expect ceilings/visibilities to deteriorate to MVFR at kmot with -sn and
blsn. Otherwise gusty westerly to northwesterly winds sustained
between 30kt and 40kt will develop across the terminals after 18z
Saturday and continue through Sunday. Low level wind shear can be
expected through Saturday afternoon.


Bis watches/warnings/advisories...
High Wind Warning from 6 PM CST /5 PM MST/ this evening to 6 am
CST /5 am MST/ Monday for ndz003-011-012-019>022-034-042-045.

High Wind Warning from noon CST /11 am MST/ today to 9 PM CST /8
PM MST/ Sunday for ndz001-002-009-010-017-018-031>033-040-041-

Blizzard Warning from midnight tonight to 6 am CST Monday for

High Wind Warning from 6 am Sunday to 6 am CST Monday for



Update...warm air advection
short term...Kansas
long term...warm air advection

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