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fxus63 kfgf 302007 

Area forecast discussion
National Weather Service Grand Forks ND
307 PM CDT sun Apr 30 2017

Short term...(this evening through Monday night)
issued at 307 PM CDT sun Apr 30 2017

Onset and amounts of precipitation will be the main headache for
the period.

The main upper low is still spinning along the Kansas/OK border,
although there have been some lead precip bands extending into
eastern South Dakota and central Minnesota. Those precip bands have been falling
apart as they approach our southeastern counties with drier air in
place and further away from the forcing. Both the high-res and
short range models keep any accumulating precip south of our
counties until after 06z, some closer to 09z or later. Given dew
points in the teens and low 20s, it does look like it will take a
while to saturate. There will be some 850mb frontogenesis
overnight, along with some increasing synoptic lift as the upper
low lifts into Iowa. Will continue to keep high pops in our
southeastern counties, trending slightly further east as most
model runs have precip from the southeast ND/Minnesota border up towards
northeastern Minnesota. Deformation zone will stay over our southeastern
counties into Monday as the upper low lifts northeast into WI.
Will continue with fairly high pops for much of the day before
starting to come down in the afternoon. Precip should taper off
completely Monday evening as the low pressure system pulls east.

Model soundings just to the southeast of the County Warning Area have temps right
at borderline for rain/snow as they become saturated later
tonight. Think there will be some decent precip rates and the snow
will be falling at night, but with the slower and further east
trend it seems that our far southeastern counties will see a few
inches at best. Gefs plumes for pkd have backed off in a big way,
with the ensemble mean now around a quarter of an inch or snow
rather than the over 6 inches they had yesterday. At this point
status quo seems reasonable until we actually see precip starting
to move into the area tonight. Will keep the Winter Weather
Advisory as we have going and keep snow amounts around 1-4 inches.

Long term...(tuesday through sunday)
issued at 307 PM CDT sun Apr 30 2017

No major impacts expected throughout the period with quiet
Spring-like weather returning late in the week and for the weekend.

Models continue to depict northwest flow aloft across the forecast
area with one weak wave passing through central North Dakota on
Tuesday, and another, possibly slightly stronger, wave closer to
eastern North Dakota and northwest Minnesota on Wednesday.
Regardless, impacts should be minimal with temperature profiles warm
enough to support just some scattered rain showers.

Dominant upper ridging then builds into the High Plains late in the
work week before the Main Ridge axis settles across our area for the
weekend. With quiet weather, the main question will be just how warm
we get as 850 temperatures and associated warm advection really ramp


Aviation...(for the 18z tafs through 18z Monday afternoon)
issued at 1234 PM CDT sun Apr 30 2017

All sites are VFR with increasing high clouds today and tonight
as a low pressure system over the Central Plains moves closer.
Think that most of the snow/rain and lower clouds will stay south
and east of the taf sites although there could be a period late in
the period where kbji sees a few snow flakes and lower clouds.
Will keep visibilities up for now and ceilings at MVFR for kbji
tomorrow morning but will adjust as the time period gets closer.
The other taf sites should remain VFR. Winds will shift around to
the east this evening and then pick up out of the northeast
towards the end of the period. Kfar and kbji could see some winds
above 15 kts with lighter speeds further north.


Fgf watches/warnings/advisories...
Minnesota...Winter Weather Advisory from midnight tonight to noon CDT Monday
for mnz024-031-032-040.


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