Area Forecast Discussion
Issued by NWS Grand Forks, ND

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FXUS63 KFGF 152141

Area Forecast Discussion
National Weather Service Grand Forks ND
341 PM CST Fri Dec 15 2017

.SHORT TERM...(This evening through Saturday)
Issued at 333 PM CST Fri Dec 15 2017

500 mb short wage shown well upstream over east central
Saskatchewn. Weak surface low noted between Dauphin and Yorkton
and this will move southeast tonight into eastern ND. Isentropic
lift does increase tonight over far eastern ND into NW MN mid
level frontogenesis is quite weak. But radar returns and reports
indicate heavier snow upstream and moving into NE ND attm and this
will spread southeast and east thru the evening. So a 1-2 inch
snowfall seems reasonable. Very little fell during the day Friday
so snow totals were cut a bit from prev fcst. Risk of freezing
drizzle while not zero appears rather low as saturated layer is a
bit deeper than preferred with this system and while dry layer
aloft moves in behind this system Saturday morning unsure if
enough lift to create any light precip in the fzdz variety. For
this reason pulled mention of fzdz. Cloudy Saturday most areas,
but some aftn sun psbl in DVL region. Milder with temps in the 20s
to mid 30s.

.LONG TERM...(Saturday night through Friday)
Issued at 333 PM CST Fri Dec 15 2017

A relatively pleasant winter day is expected Sunday constructed by
light winds, high temperatures in the 20s and 30s, clouds clearing
from west to east, and dry conditions. Dry conditions are expected
despite an upper level trough moving through due to surface high
pressure at the surface and lack of moisture aloft.

On Monday, an upper level jet max pushes its way south of the area
putting North Dakota and northern half of Minnesota into the
cyclonic side and left exit region of the jet. Simultaneously a well
developed mid latitude cyclone will move through central Canada
sweeping an associated cold front/surface trough eastward through
the Northern Plains. Reinforced by the aforementioned jet max, a mid
level short wave will enhance precipitation chances later Monday
within the vicinity of the surface trough. At the moment, it seems
this will happen within the northern half of Minnesota giving
eastern counties snow chances late Monday. Ahead of the surface
trough Monday will be warm temperatures well into the 30s with some
lower 40s into the southern Valley.

Stronger winds of 35-45 kt within the H8-H9 layer, tightening of the
surface pressure gradient, and cold air advection should signal
gusty winds early Tuesday, however there is some degree of
uncertainty of steep lapse rates very near the surface which could
limit mixing of strongest winds to the surface. Best chance of gusty
northwest winds into wind advisory criteria would be mid to late
morning Tuesday before the bulk of strongest winds exits to the
east. Dependent on how much snow is received late Monday will be
chance of blowing and drifting snow potential Tuesday. Winds
gradually ease Tuesday afternoon.

The next system to impact the region looks to be Wednesday into
Thursday. Run to run model guidance still prevents talking of
snowfall placement and amounts, although a favorable low track to
the south of the area would give better chances of snowfall during
this time. Behind the system is advertised to be the intrusion of a
colder airmass which would bring temperatures to near or
below seasonal normals.


.AVIATION...(For the 18Z TAFS through 18Z Saturday afternoon)
Issued at 1215 PM CST Fri Dec 15 2017

Ceilings to be mainly in the MVFR range thru the pd at most sites.
Though VFR at DVL until tonight. Vsbys varying from as low as 1-2
SM in light snow tonight to unrestricted.




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