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Area forecast discussion 
National Weather Service Grand Forks ND
1244 PM CST Friday Nov 28 2014

issued at 1243 PM CST Friday Nov 28 2014

A few minor tweaks for current radar trends...but otherwise no
major changes for this update.

Update issued at 946 am CST Friday Nov 28 2014

There have been some reports of sleet and freezing rain in a few
spots in our southwestern counties...which is supported by BUFKIT
soundings. Given the scattered nature of the freezing rain/sleet
showers and the fact that the short term models have this activity
dissipating in the next hour or so will keep any headlines out for
now and just go with a Nowcast. However will keep an eye on things
in case the activity persists longer than expected.

Update issued at 706 am CST Friday Nov 28 2014

Will maintain a scattered type pop this morning over the forecast
area. Radar has been showing some very light snow moving into dvl
basin-Langdon areas. Of more interest is convective showers that
were in eastern Montana earlier they are moving quickly toward Lisbon-
Valley city and will move into Fargo area. Coverage has diminished
a tad....but ptype is what is most important. BUFKIT soundings
would indicate sleet possible in Jamestown but then more of a snow
sounding farther east as depth of cold air is quite deep as you
move east. For now will maintain previous ptype grids which is snow
for Valley City-Fargo and some sleet/snow in Forman/Gwinner area.


Short term...(today through saturday)
issued at 322 am CST Friday Nov 28 2014

Models have in general handled things very poorly lately. What was
going to be a decent snow clippery system last night was anything
but. Baroclinic zone remained well south and west of what was
prognosticated 24 hours ago and thus main 1 to 2 inch band was from Minot
area to Jamestown to Alexandria Minnesota instead of being farther north.
Amounts weaker as well as focus of warm advection and lift seemed
more confined to eastern South Dakota/west-central Minnesota just outside of main precipitation
band. Anyhow first precipitation band of light snow eastern Minnesota into
Wisconsin. There is a larger area of light snow upstream in
Saskatchewan into SW Manitoba and trying to spread into north central ND.
Latest rap/NAM seem OK in showing this light snow spreading into
northern valley and parts of northwest Minnesota this morning before drying up. There
is an area of convective showers that formed in ecntrl montanta
and is now northwest of Bismarck. Rap has some precipitation surviving
and moving into parts of ecntrl or southeast ND 12z-15z period. So with
chances of light snow north and south kept pretty broad probability of precipitation through
18z Friday. Top down did show some risk of sleet in far southeastern
ND if precipitation reaches that area. This afternoon pretty quiet most
areas...though lingering light snow chances far north. But main
850 mb warm advection returns back to central Saskatchewan this
afternoon ahead of shrot wave and surface low in southern b.C. This system
to move into north central ND Saturday morning with main area of
warm advection snows north of the international border. Though did keep some probability of precipitation
in northern forecast area as southern edge may impact areas along the border.
Quite warm air builds into the southern half of the forecast area
later tonight into Saturday so highs today will be near lows
tonight in many areas and then rising to some lower or middle 30s in
the far south Saturday with south winds while north winds return
to dvl basin and far northern valley as low moves east.

Long term...(saturday night through thursday)
issued at 322 am CST Friday Nov 28 2014

Low will move east through northern Minnesota with cold front moving south through
the forecast area. Some light snow with front but nothing much. Very
cold airmass moves in Sunday with highs likely staying below zero
in far northern ND. High pressure moves in Sun night into central ND
with clear sky and did go a bit lower than superblend based on Wednesday
nights lows. Suspect -20s again in the dvl basin.

Monday to Thursday...overall dry and cold as the period begins with
surface high pressure centered over the northern plains and an Arctic
airmass in place. The next short wave moves across the international
border on Monday night into Tuesday allowing for weak and brief
ridging scouring out the well below normal cold airmass. Northwest flow in
the wake of this short wave is not as amplified...resulting in a
less cold airmass...with 850mb temperatures in the 10 to 18 below range for
Wednesday. Zonal flow appears to develop up Thursday with temperatures
rebounding into the 20s.


Aviation...(for the 18z tafs through 18z Saturday afternoon)
issued at 1243 PM CST Friday Nov 28 2014

Abundant moisture and weak forcing yielding areas of
IFR/MVFR ceilings/visibility this morning. Shallow low level boundary forecast
to shift slowly north through00z. Low risk -frdz/pl near the
boundary where moisture and lift are maximized. Although this
boundary should lift north during this period expect slow
improvement kdvl-kgfk-kbji line. South of boundary visibility should show
gradual improvement and decrease -sn/pl/-frdz risk. Observation and lamp
guidance suggest VFR after weak boundary lift past taf site. However
timing is very problematic as boundary will be slow to move north.


Fgf watches/warnings/advisories...


short term...Riddle
long term...jk/Riddle

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