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Area forecast discussion 
National Weather Service Grand Forks ND
401 am CST Monday Nov 30 2015

Short term...(today through tuesday)
issued at 401 am CST Monday Nov 30 2015

Snow timing and amounts continue to be the primary forecast
headache for the short term.

The upper low continues to spin over Colorado and Wyoming...with some radar
returns beginning to extend into South Dakota but not much reaching the
ground yet. The short range models all have precipitation staying south
of the County Warning Area through 18z at think we will stay dry
through much of the morning. Snow will start in by late in the day
and should continue for much of the night. There is plenty of
synoptic lift to work with as the upper system comes out into the
plains...but not much indication at this Point of frontogenesis
that would be good for mesoscale banding. The time height plots
for our southeastern County Warning Area have a brief period of good Omega in the
-15 c layer that is favorable for dendrite growth...but relative humidity is not
really abundant in that layer. Think that snow will be more an
extended light snow event rather than heavy amounts in a short
amount of time.

With light snow piling up over a long period...think that our
criteria of 6 inches in 12 hours or 8 in 24 will be hard to reach.
The NAM and GFS have trended ever so slightly back south...and the
European model (ecmwf) is still further north but not putting out as much snow
accumulation as the other models. Even the more bullish members of
the sref ensemble have the southeastern County Warning Area staying below 6 inches
until late in the day Tuesday and in general have been backing off
on amounts. After coordination with neighbors...will put out a
Winter Weather Advisory from where we have the old watch and
extend it north towards the Highway 200 corridor. Think that snow
accumulation will stay below 6 inches in our southern counties through
tomorrow morning and then only slowly add in a bit more before
tapering off Tuesday evening. Further north snow should stay in
the 2 to 5 inch range. Winds will not be an issue and should stay
around 15 miles per hour or below.

Long term...(tuesday night through sunday)
issued at 401 am CST Monday Nov 30 2015

Tuesday night through Wednesday night...conditions will be quiet
with a ridge building in behind the departing upper low. No real
cold air advection behind this system so temperatures will be impacted
most by clouds and snow cover. Southeastern counties will remain
in the 20s Tuesday night with lingering clouds but will be the
cold spot Wednesday and Wednesday night with fresh snow. Further
north there will be the opposite with clearing skies Tuesday night
and winds keeping temperatures up Wednesday night.

Thursday through Sunday...long term will generally be dominated by
long wave upper ridge moving across the central Continental U.S./Canada late
this week. SW flow pattern sets up over the weekend...but models
indicating Pacific moisture in the Pacific northwest scouring out as long
wave trough moves across rockies...resulting in a dry upper wave
moving across the region Saturday night and keeping dry forecast
with moderate temperatures in the middle 30s for the entire long term


Aviation...(for the 06z tafs through 06z Monday night)
issued at 1146 PM CST sun Nov 29 2015

Clouds were across the area except for counties along the
international border. VFR ceilings ranged from 45 hundred to 60 hundred
feet. Expect ceilings to remain about they are through Monday late morning or
early afternoon. Then expect ceilings to fall into the MVFR categories
by late Monday afternoon or early evening.


Fgf watches/warnings/advisories...
ND...Winter Storm Watch from this afternoon through Tuesday afternoon
for ndz052-053.

Minnesota...Winter Storm Watch from this afternoon through Tuesday afternoon
for mnz029>031-040.



Short term...Jr
long term...Jr/speicher

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