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Area forecast discussion 
National Weather Service Grand Forks ND
310 PM CST Sat Dec 20 2014

Short term...(this evening through Sunday night)
issued at 310 PM CST Sat Dec 20 2014

Forecast challenges will be the precipitation moving through the forecast area tonight
and then the potential for a Monday/Tuesday snowfall. As of middle afternoon
fog still covered the entire forecast area with a few patches of dense fog
still up around Cando/Langdon. Regional radar showed a band of
very light precipitation from Bottineau down through kjms moving to the east
at about 20kts. Kbis did get a trace of fzdz as this moved through
them and now k06d is reporting unknown precipitation. Think this will
remain pretty light fzdz possibly mixed with some light snow as it
moves through tonight. At this point think it will stay a thin band
as it moves east through ND and be pretty minimal. There is also some
comma head precipitation moving into far northwest ND now associated with the middle
level wave. Therefore there could be a little additional precipitation
along the Canadian border later associated with this feature.
Models show the thin band possibly strengthening as it moves into
northwest Minnesota later this evening with a dusting to an inch of snow
possible there. Since fog still remains over the entire forecast area will
mention that into Sunday morning too. Not sure about dense fog and
will let later shifts monitor that. There is some clearing over
southwest ND with west/SW winds but do not expect winds to switch
to that direction to help scour out the fog/stratus here. Not
sure if fog will scour out on Sunday either so bumped up sky
amounts then too.

Long term...(monday through saturday)
issued at 310 PM CST Sat Dec 20 2014

By 00z Tuesday the surface low should move into the ND/SD/MN border region
setting up a decent snow band over eastern ND/extreme northwest
an inverted trough. This mainly stays the set up into Monday night or
early Tuesday before shifting off to the east. This is using the 12z
European model (ecmwf)/NAM with the other models a little different. Looking at
raw snowfall from the European model (ecmwf)/NAM would bring up to 6 inches over
eastern ND/far northwest Minnesota. At this time wpc shows about 4-6 inches from
east central ND into northwest Minnesota. Still some uncertainty...but will
issue an Special Weather Statement to highlight the transition back to snowier weather.

For Tuesday night through Friday...main challenge is precipitation amounts
and winds on back side of departing low pressure over the Great
Lakes on Tuesday night into Wednesday. Models differing somewhat in
placement of precipitation band...but for the most part putting it east of
the Red River. Looking for precipitation to be in the form of snow as maximum
temperatures aloft range from -4c to -7c...and colder air will continue to
wrap behind the system. Winds should begin to decrease as pressure
gradient weakens...and surface high pressure takes over by Christmas day
bringing drier conditions. Otherwise...expect cooling temperatures
and a slight chance for precipitation near the end of the period.


Aviation...(for the 18z tafs through 18z Sunday afternoon)
issued at 1144 am CST Sat Dec 20 2014

IFR/LIFR conditions remain widespread across the area. Stayed with
persistence for this taf period as not seeing significant changes in
the airmass. Otherwise...visibilities are expected to fluctuate and
show some improvement in areas...but overall trend is to remain
mainly in the IFR category.


Fgf watches/warnings/advisories...


Short term...godon
long term...godon/Hopkins

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