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Area forecast discussion 
National Weather Service Grand Forks ND
310 PM CST Thursday Nov 27 2014

Short term...(this evening through Friday night)
issued at 310 PM CST Thursday Nov 27 2014

Snow coming into the area this evening and what to do with
headlines will be the main challenge for the short term.

Surface observation show the region under the influence of the Arctic
high...with temperatures in the gingle digits this afternoon over the
County Warning Area. Not very far west though...a surface trough extending from the
northern rockies into the western Dakotas has helped some good
warm air advection to develop. Temperatures in the eastern rockies are in
the 30s and 40s...and while readings have remained below freezing
in western ND...there has been enough warm air aloft to bring
freezing rain to southwestern portions of the state.

Tonight...the frontal boundary extending from northwest to
southeast across ND will move very slowly northeastward. This
should bring some good isentropic lift to the County Warning Area beginning this
evening and continuing into the morning hours. The models have all
been trending further south with the snow band that develops...now
more from Devils Lake down towards the Fargo area rather than
further north. Will have to keep a close eye on mesoscale model runs to
see if this trend continues. For now will just extend the
advisory a bit further south and keep the northern border as it is
rather than cancel and have the band be further north than current
model runs show. There is some weak frontogenesis and a little bit
of q vector convergence...but not a huge amount. Think that snow
amounts will be pretty marginal...around 2 to 3 inches...but given
the heavy travel day will keep an advisory going.

The frontal boundary will continue to lift northward across the
County Warning Area during the day tomorrow...allowing temperatures to rise overnight and
reach back into the teens to low 20s by afternoon tomorrow. The
first round of snow from the isentropic lift that developed
overnight will move off to the east during the morning...and there
should be a bit of a break before the main surface low begins to move
out into the plains Friday night and Saturday. Most of the
solutions keep the best precipitation to the north of the international
border...so will keep some 30-40 probability of precipitation in our north Friday
afternoon into Friday night. South winds should keep lows mainly
in the teens Friday night.

Long term...(saturday through thursday)
issued at 310 PM CST Thursday Nov 27 2014

Saturday and Sunday...the positively tilted upper trough will dig
down into the plains and begin to amplify Sunday. The surface low will
head quickly off into the Great Lakes and very cold high pressure
builds into the region again. Some light snow will be possible
with the passage of the front...but not very much is expected so
continued with minimal probability of precipitation and quantitative precipitation forecast. The main issue will be winds
with strong cold air advection Saturday afternoon and Saturday
night. Kept it just breezy for now but models may be underdoing
speeds. Much of the County Warning Area will be ahead of the front on Saturday and
should be pretty mild at least early on...but with the cold front
coming in Saturday night should drop below zero in spots and
sundays highs only in the single digits.

Monday through Thursday...the long term will start out with surface
high pressure over the region and an northwest flow pattern aloft
consisting of a SW ridge over Saskatchewan that will sink into the
northern tier early next week. Models in decent agreement with
upper level pattern but show considerable difference in placement
of surface high. Either way...next week will start with dry weather
and a bitter cold Arctic airmass in place over the northern tier.
The placement of that high in relation to calmest winds during
Sunday night and early Monday morning will impact just how cold we
get. Return flow sets up Monday night...and we could see steady to
rising temperatures through Tuesday morning when temperatures rebound and climb
into the upper teens to around 20 by late Tuesday afternoon. Some light
snow associated with the warm advection is also possible through
Tuesday. GFS/emcwf then show difference with the GFS having more
zonal flow aloft than shown in the European model (ecmwf). By Wednesday night the GFS
kicks a surface low out into the Central Plains and the upper flow
pattern is about 180 degree out of phase with the European model (ecmwf) (showing a SW
ridge moving into western dakotas). Therefore superblend low probability of precipitation seem
reasonable but very little confidence on snow potential for middle to
late next week. Temperatures...however...will moderate and daytime
highs in the middle teens to low 20s are probable.

&&

Aviation...(for the 18z tafs through 18z Friday afternoon)
issued at 1248 PM CST Thursday Nov 27 2014

VFR conds will continue through 00z this evening. A low pressure
system will move across the northern tier and bring MVFR to IFR ceilings
across North Dakota and northern Minnesota. Ceilings should begin to
decline in dvl around 00z...the Red River valley around 03z...and
into sites in northwest Minnesota (bji/tvf) by midnight. Light to moderate
snow will keep visibilities and ceilings in the MVFR range through 12z to 15z
Friday morning.



&&

Fgf watches/warnings/advisories...
ND...Winter Weather Advisory from 9 PM this evening to noon CST
Friday for ndz008-016-027-029-030-039.

Winter Weather Advisory from 6 PM this evening to noon CST
Friday for ndz006-007-014-015-024-026-028-054.

Minnesota...Winter Weather Advisory from 9 PM this evening to noon CST
Friday for mnz001>004-007-008-013>017-022>024-027-028-
030>032.

&&

$$

Short term...Jr
long term...Jr/speicher
aviation...speicher

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