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Area forecast discussion 
National Weather Service Grand Forks ND
351 PM CST Thursday Dec 25 2014

Short term...(this evening through Friday night)
issued at 350 PM CST Thursday Dec 25 2014

Series of short waves will move across the area through the period.
Cold air over Saskatchewan will shift south and east tonight and Friday and
brush the area. Cold air will be tempered Friday night and Sat or ahead of
the next shot of cold air on Sat night and sun. A strong short wave
will move across man and Ontario Sat and sun and in its wake will
send the cold air into the northern plains.

Radar showing a few weak echoes this afternoon and a few reports
over southern Canada. Will add flurries for this evening. 700 hpa
frontogenesis was located over South Dakota and the far southern zones today
and shifts south and east Friday morning. Model cross sections indicate
wedge of dry air between 850 and 500 hpa across the forecast area
for today and tonight. Dry wedge shifts south Friday and Friday night.
Will lower probability of precipitation along the southern border for tonight and Friday
morning.

Next chance of precipitation will be Sat night and sun but will be very low
quantitative precipitation forecast.

High temperatures generally raised a degree or so for Friday and Sat and
decrease a couple degrees for sun.

Long term...(saturday through thursday)
issued at 350 PM CST Thursday Dec 25 2014

Middle Range guidance still indicating high pressure between 1050-1060
mb descending upon northern High Plains by Tuesday. This feature
will efficiently keep precipitation well south of the forecast area
essentially through middle week...suppressing it over central rockies
to Central Plains. Lack of/minimal snow cover will play a role in
figuring out temperature regime through this time frame. 1000-500 mb
thicknesses plunging to near the 500 dm mark for Monday and Tuesday
would suggest near zero to positive single digit high temperatures.
Bias corrected temperature grids are trending warmer seemingly adjusting to
lack of snow cover which would be included for this time of year in
the gridded/statistical output. Forecast still has some marginally
sub zero highs along northern tier Monday...transitioning to middle and
upper teens by Wednesday as westerly flow becomes established. Have
included slight probability of precipitation to address short wave to ring in the New
Year...followed by an end of week cool down.

&&

Aviation...(for the 18z tafs through 18z Friday afternoon)
issued at 100 PM CST Thursday Dec 25 2014

Low level moisture will hang around for duration of upcoming taf
period...mainly MVFR ceilings with some short lived IFR through late
afternoon. Surface north-northwest winds at or below 10kts should prevail through Friday.



&&

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

$$

Short term...hoppes
long term...wjb
aviation...wjb

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