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Area forecast discussion 
National Weather Service Grand Forks ND
1000 am CST Thursday Dec 25 2014

Update...
issued at 959 am CST Thursday Dec 25 2014

Water vapor loop indicated a short wave trough over southwest
Ontario and was moving east. Another upper level trough was over
southern Saskatchewan with some flurries over southern Saskatchewan. Trough was
moving southeast but is expected to turn more east. Flurries more
likely in the northern zones. Will keep flurries as is. Tweaked
winds down a bit. No other changes at this update.

Update issued at 634 am CST Thursday Dec 25 2014

No update necessary.

&&

Short term...(today through friday)
issued at 330 am CST Thursday Dec 25 2014

Forecast challenges concern snow chances across the far south and
temperatures. NAM/Gem coming around to more consistent...farther
south solution of the GFS/European model (ecmwf) and will follow later for forecast.

Models now in good agreement in organizing snow band in zone of
increasing frontogenetic forcing across north half of South Dakota into
adjacent portions of Minnesota. The ND/South Dakota border area remains on northern
fringe however latest model runs even farther south. With good
model agreement trimmed back on probability of precipitation and snow amounts along the
border. Elsewhere across the region in the wake of the passing
cold front steady cold advection today. Combined with moist low
levels flurries a good bet. Model soundings showing some potential
for fzdz however until we receive reports will leave out of
forecast. With stratus spreading back into the forecast area any temperature
recovery will be minimal if at all.

Cold advection continues overnight and temperatures will hinge on
how much of the forecast area can lose clouds. Any decreasing cloud potential
looks to be across the western forecast area and will have coldest minimums there.

High pressure continues to build in Friday. With drying column
will have a better chance of seeing solar across the region. Cold
advection levels off and little if any snow on the ground so
forecasting maximum temperatures may be a challenge at this point
held pretty close to persistence.

Long term...(friday night through wednesday)
issued at 330 am CST Thursday Dec 25 2014

Secondary cold front Friday night will allow colder air to seep
southward into the forecast area for continued downward temperature trend.
Next chance for snow still looks Sat night as weak impulse drops
southeast along baroclinic zone.

Sunday-Wednesday...both the 00z GFS/European model (ecmwf) indicate a surface boundary
dropping south into Sunday ahead of a strong 1050mb+ Arctic surface high
which will build into the High Plains for early week. There
could be some light snow/flurries on Sunday with the
boundary...followed by dry and cold conditions for Mon/Tue. Temperatures
may stay near or below zero during the day in some areas
Mon/Tue...although the lack of deep snowcover in many areas may
impact temperatures. The global models maintain northwest flow aloft during
the middle-week time...although differ on the timing of embedded
shortwave troughs...affecting the position of the low-level
baroclinic zone/surface temperatures and any light snow chances.
Regardless...no significant precipitation is expected through the period.

&&

Aviation...(for the 12z tafs through 12z Friday morning)
issued at 634 am CST Thursday Dec 25 2014

Mainly MVFR stratus spreading back into the forecast area in wake of cold
frontal passage. Ceiling heights may be a challenge with ceilings ranging
from 5 to 2500 hundred feet. Could also see some flurries but
should not affect visibility.



&&

Fgf watches/warnings/advisories...
ND...none.
Minnesota...none.
&&

$$

Update...hoppes
short term...voelker
long term...makowski/voelker
aviation...voelker

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