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Area forecast discussion 
National Weather Service Grand Forks ND
716 PM CDT Sat Mar 28 2015

issued at 711 PM CDT Sat Mar 28 2015

South winds will continue this evening ahead of a cold front which
is entering western ND. Band of thunderstorms formed and located west of
Garrison to near Glen ullen to southeast of Dickinson. Instability
enough in that area for thunderstorms...but this ribbon of unstable air
does weaken by 02z as it gets closer to our western forecast area. Thus
will maintain shower mention as predominate weather. Did tweek
temperatures just a tad up tonight and doing so would limit any -sn/rain
mix to far NE ND/northwest Minnesota for just a few hours 11z-15z period. Kept
timing of showers and probability of precipitation otherwise as it was.


Short term...(this evening through Sunday night)
issued at 310 PM CDT Sat Mar 28 2015

Forecast challenges revolve around approaching cold front and
associated pcpn/type/phase...wind and temperatures. Models in
reasonable agreement and used a blend mainly with wind speeds.

Potent short wave crossing northern rockies will cross forecast area later
tonight into early Sunday. Prefrontal trough should be along
western/central Dakotas border area around 00z with cold front
catching up later tonight. Cold front will then nearly be through
the forecast area by 12z Sunday. Based on high resolution models rain showers along
boundary should reach western forecast area by middle evening and the valley by
midnight...continuing east during the overnight. Precipitable water values
approach an inch later tonight so could see some moderate but likely
spotty rain amounts. Showalter indices approach zero over west
central Minnesota along with low level jet convergence. While models not
indicating any elevated cape would not be surprised to see a few
lightning strikes however confidence not high enough to put into
forecast. As column cools late tonight there may be a rain/snow
mix however no accums expected as minimum temperatures should for
the most part be at or above freezing.

Wind will be a concern late tonight into Sunday. Strong/rise fall
surface pressure couplet along with push of cold advection and
30-40+ kts through deepening mixed layer will result in strong
winds. Winds to develop late tonight over dvl basin spreading east
during the early am. Sufficient wind expected to issue a Wind
Advisory across all but the more wooded area over the far eastern
forecast area. Thermal advection not long lived and with clearing in wake of
cold front passage should still be able to see some temperature recovery.

Winds will diminish Sunday night allowing temperatures to drop
close to freezing.

Long term...(monday through saturday)
issued at 310 PM CDT Sat Mar 28 2015

Weak boundary will cross forecast area on Monday and models becoming a little
closer on timing and location of potential precipitation...across the NE
half of the forecast area. Made some minor pop adjustments based on better
model agreement. Degree of cloud cover will impact temperatures
but column fairly mild.

Column a bit cooler Tuesday but temperatures should still range
well above average.

Tuesday night through Saturday...
an upper level ridge axis will be centered over the Dakotas Tuesday
night. upper level trough will make its way eastward
from the Pacific northwest Tuesday night and through the area on Wednesday.
Southerly winds will increase ahead of the low pressure system
Tuesday night. Winds will then switch to the west and northwest...
ushering in cooler air for Thursday. The good news is that Wednesday
is expected to be much above average with highs around 60 degrees.
Precipitation with this system looks to be mainly south or north of
the region...leaving the area with low chances for precipitation. Cool high
pressure will follow the low for Friday and Saturday. However...the
GFS is a little more progressive with the next approaching upper
trough off the Washington/or coast compared to the European model (ecmwf)...favoring a warmer
Saturday. Current official forecast takes a middle of the Road


Aviation...(for the 00z tafs through 00z Sunday evening)
issued at 711 PM CDT Sat Mar 28 2015

Showers will move east through the area overnight. Kept timing per
previous 18z taf issuance. However based on upstream observation behind
the rain showers didnt go as low of ceilings as some guidance
suggests. Looks like a brief period of MVFR ceilings possible on backside
of showers once cooler air aloft moves in. Clearing will work in
pretty quickly behind system for Sunday along with a strong
northwest wind 25 to 40 kts....20 to 30 kts in Bemidji area.


Fgf watches/warnings/advisories...
ND...Wind Advisory from 7 am to 7 PM CDT Sunday for ndz006>008-

Minnesota...Wind Advisory from 7 am to 7 PM CDT Sunday for mnz001>005-007-



short term...voelker
long term...knutsvig/voelker

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