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Area forecast discussion 
National Weather Service Grand Forks ND
100 PM CST Sat Jan 31 2015

Update...
issued at 1257 PM CST Sat Jan 31 2015

Dry low level cold air continues to push the stratocu south and
out of the area. Do have some cirrus moving eastward and thickest
in dvl basin as expected. Otherwise other than some very low probability of precipitation
in the far west and far southwest dry. Temperatures steady in most spots
now that the afternoon is arriving. Wind chills near -25f in NE ND
at this time and this will become more widespread this evening/tonight in NE
ND/northern Red River so a wind chill advection probably needed next update.

&&

Short term...(today through sunday)
issued at 340 am CST Sat Jan 31 2015

The main concerns this weekend will be the return of colder air and
low end snow chances.

A marked change from temperatures yesterday is underway with strong
low-level cold advection this morning in advance of a 1045 mb surface
high that will drop south over the northern plains for tomorrow. With
continued cold advection expect temperatures to gradually drop through
the day...although how fast temperatures fall will need to be monitored.
Although boundary layer winds will only be around 25
kts...effective mixing should lead to gusty winds at times. This
is supported by mav guidance at Grand Forks/Fargo in the 15-20 knots
range this afternoon with northerly winds. Combined with the
falling temperatures...it will be quite the change from yesterday. It
still appears the band of light snow associated with weakening
middle-level frontogenesis ahead of the Arctic high will skirt parts
of the Devils Lake basin into far southeast ND/wc Minnesota later today and
tonight...with a few flurries possible elsewhere. With dry north-northeast
low-level flow across the area...it may be tough to fully saturate
the dry low- level layer. Deep layer q-vector convergence favors
the far southwestern part of the area for any precipitation though...with
the highest probability of precipitation in this area. At this point do not expect more
than an inch...on the high end.

The question tonight concerning temperatures will be cloud cover. The surface
high will build in from the north...with 850 mb temperatures around -20c in
the north by early Sunday. The best chances for clearing will be
over the north...although model soundings indicate some middle-level
moisture overnight though. Thus...kept the coldest low temperatures up
near the international border...with warmer readings farther
south. These temperatures will ultimately hinge on the amount of cloud
cover...though. With winds remaining at least in the 5-10 knots
range...wind chills may be an issue...and right now it looks like
the best chance for wind chills below -25f will be along or north
of Highway 2. However...it will be a blustery night over the
entire region.

Sunday will feature more sunshine...although it will be very
cold...with the surface high overhead. Did continue to trend on the
higher side of guidance for temperatures...given the lack of snow cover.
Wind chills will likely remain below zero during the day.

Long term...(sunday night through friday)
issued at 340 am CST Sat Jan 31 2015

Another cold night is in store for tomorrow night as the surface high
begins to slide south. Winds will gradually turn southerly with
developing warm advection...but this will likely take longer to
occur over northwest Minnesota...and have the coldest lows in this area.
However...a quick drop-off may occur area-wide during the evening
with light winds.

Temperatures on Monday will moderate closer to seasonal averages ahead of a
weak upper shortwave trough. Did include some low chances for
light snow over far southeast ND by Monday afternoon...but this system
appears very weak.

For Tuesday through Friday night...a weak clipper will bring the threat for
some light snow to mainly the southern 2/3 of the region on Tuesday.
Colder air will move into the area for the Wednesday/Thursday timeframe. There
will be some moderating temperatures and the chance for some light snow as
we head towards next weekend possibly. For now will leave Friday dry
though with timing issues this far out. No major storms are expected
though as the general west/northwest flow aloft continues.

&&

Aviation...(for the 18z tafs through 18z Sunday afternoon)
issued at 1257 PM CST Sat Jan 31 2015

Arctic high pressure shunting clouds farther south and west allowing
VFR ceilings and visibility with cirrus or sky clear the next 24hrs. Gusty north
to northeast winds weakening this evening...still sustained in the
valley 12 to 18 kts overnight...slowing to under 10kts by morning.



&&

Fgf watches/warnings/advisories...
ND...none.
Minnesota...none.
&&

$$

Update...Riddle
short term...makowski
long term...dk/makowski
aviation...jk

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