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FXUS63 KFGF 260956

Area Forecast Discussion
National Weather Service Grand Forks ND
356 AM CST Sun Feb 26 2017

.SHORT TERM...(Today and tonight)
Issued at 346 AM CST Sun Feb 26 2017

Challenges for the forecast today and tonight will revolve around
placement and timing of light snow possible this late afternoon
west and moving into the central valley and western MN tonight.
Small dense fog area in the southern valley is expected to improve
as next round of snow moves in over the next couple hours. This 
mornings central valley snow is moving into west central MN with 
another inch or so possible before mid morning. Max temps today 
about 10 degrees cooler than yesterday with SFC high expected to 
bring light winds and 925mb temps 4 to 6 degrees lower than 
yesterday with temps ranging from middle teens north to middle 20s

Next compact wave in the broad 500mb trough expected to bring 
light snow into the west by late this afternoon into the  
evening. Pwats to increase from a tenth to near a quarter of an
inch so not much moisture to work with but similar to Saturdays 
event where up to 4 inches of snow was produced. Low to mid level
frontogenesis appears to set up tonight across the southern
Devils Lake basin and into the central valley however the 500mb 
divergence with this next wave appears weaker than the previous 2 
waves from Saturday night and this morning. So thinking is that 
only an inch or so of snow will be possible. Placement may have to
be adjusted as the system organizes and better consensus develops
in the hires model solutions today. 

.LONG TERM...(Monday through Saturday)
Issued at 346 AM CST Sun Feb 26 2017

Monday morning will see the departure of a compact area of light 
snow in the east and SFC high pressure to the northwest bringing 
drier air into the area with north to northeast winds. The SFC 
high and developing low pressure in SD will create a low level 
area of convergence and a baroclinic zone across the far southern 
FA Monday night into Tuesday morning. This convergence combined 
with 500mb divergence will set the stage for a band of snow to set
up. If some mid level frontogenesis develops which the NAM 
suggests is possible although very transitory in the current 
00/06z runs then a narrow band of intense snowfall rates will be 
possible tuesday morning. 

Wednesday through Friday...The medium range models are in fairly 
good agreement an active start to the period with a shortwave trough 
moving into the Red River Valley on Wednesday. Surface low is fairly 
weak but tracks from ND into MN. Will continue a broad area of 30-40 
POPs moving through and exiting Wednesday night. Thursday will see 
another shortwave moving through, but this time from western ND into 
southern MN as the flow amplifies and becomes more northwesterly. 
Our southwestern counties could be clipped with snow, but most of 
the activity will be out of our area and we should be quiet and cool 
with high pressure building in. Slightly colder air starts to move 
down as the flow amplifies, and Thursday night could see temps in 
the north dropping below zero depending on clouds. The cold air will 
be short lived however, as heights start to rise on Friday. Kept 
some low POPs in the north with the warm air advection and have 
highs rising up above seasonal averages. 

Saturday and Sunday...The upper ridge starts to come down again as a 
shortwave trough moves through southern Canada Saturday. This will 
help push a surface trough axis through, but the south winds 
becoming westerly will bring more warm air and highs will top out in 
the unseasonably warm 30s and 40s. The models start to diverge a bit 
by Sunday, as all the deterministic runs bring a shortwave into the 
area but the GFS is further south over ND and much more vigorous. 
With high uncertainty will keep the blended solution for POPs.


.AVIATION...(For the 06Z TAFS through 06Z Sunday night)
Issued at 1209 AM CST Sun Feb 26 2017

Believe periods of snow will limit visibilities to a mile or so
along with MVFR to IFR cigs at times. This system will be out of
the area after expect BJI and FAR to improve shortly
after that.


ND...Dense Fog Advisory until 6 AM CST early this morning for NDZ053.

MN...Dense Fog Advisory until 6 AM CST early this morning for MNZ029-


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