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Area forecast discussion 
National Weather Service Twin Cities/Chanhassen Minnesota
406 PM CST Sat Dec 27 2014

Short term...(this evening through sunday)
issued at 243 PM CST Sat Dec 27 2014

In what has been a very rare occurrence this month...the sun has
finally made a pretty lengthy appearance this afternoon following
the exiting storm. Temperatures and dew points have been holding
nearly steady...except they have risen a bit across western Minnesota. Clear
skies will continue into the evening hours before clouds increase in
advance of a cold front set to push through Sunday. Therefore...
thinking temperatures will drop rather quickly this evening with the
fresh snowpack around before bottoming out and holding steady
overnight. The sun has led to modest melting today and with a pretty
good shot at reaching the crossover temperature this evening...there
may be some patches of freezing fog. Left it out for now but will
need to monitor this evening.

The Arctic cold front will push south Sunday. Highs will likely be
reached by late morning before cold air advection kicks in. Steepening low level
lapse rates may bring a few flurries...but most of the moist layer
is above -15c so kept a dry forecast going.

Long term...(sunday night through saturday)
issued at 243 PM CST Sat Dec 27 2014

The main story in the long term is the return of the cold. The
only chance of light snow anywhere in the forecast area comes on
Monday with a second surge of colder air. This will likely be the
coldest air since last February. The Monday system is becoming a
little clear and most of the guidance take the precipitation west and
south of the forecast area. The European model (ecmwf)/GFS continue to be dry and
the sref continues to be the most aggressive with developing a
weak wave along the surging Arctic boundary and spreading snow
across at the far southern and western portions of the forecast
area. The sref probabilities for >1" and >4" snow in 12 hours have
dropped considerably from yesterday. At this point...the forecast
doesn't reflect the potential for accumulating snow. Regardless of
whether or not there is snow on Monday or if the Arctic boundary
simply comes through with stratus or flurries...the air mass to
follow is cold. There is good agreement on -18c to -22c at 850mb
across the forecast area. With snow on the ground /which most of
the forecast area has now/...that type of air mass can yield near or
sub zero highs...but at the very least...a few days of below zero
lows are likely if skies are clear. Temperature departures should
be in the 10 to 20 degrees below normal range.


Aviation...(for the 18z tafs through 18z Sunday afternoon)
issued at 1202 PM CST Sat Dec 27 2014

VFR is in place for most of Minnesota at taf issuance time...with the
back edge of the stratus nearing msp. The clearing will push
over the WI taf sites through middle afternoon. Northwest winds will
back southwest this evening...then become northwest again Sunday
behind a cold front.

Kmsp...MVFR ceilings expected until about 19z...then VFR through much
of the period. Could see some MVFR ceilings return Sunday afternoon.

/Outlook for kmsp/
Sun night...MVFR possible early. Winds north 5-10 kts.
Monday...VFR. Winds north 10 kts.
Tuesday...VFR. Winds northwest 5-10 kts


Mpx watches/warnings/advisories...


Short term...borghoff
long term...clf

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