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Area forecast discussion 
National Weather Service Duluth Minnesota
1137 PM CST Sat Feb 13 2016

issued at 1008 PM CST Sat Feb 13 2016

Dropped min temperatures a few more degrees along the boundary waters
canoe area wilderness as prior forecast min temperatures have been

Update issued at 841 PM CST Sat Feb 13 2016

Pushed back the light snow start time even further. Latest
hrrr/rap indicate that this light snow may even fall apart by the
time it reaches the far western edge of the forecast area. As a
result...have also lowered probability of precipitation Sunday morning. Previously
forecast min temperatures have been reached over a portion of the Minnesota
arrowhead and a few other spots. Have lowered min temperatures everywhere
a few degrees.

Update issued at 620 PM CST Sat Feb 13 2016

Delayed the onset of the light snow a few hours over the western
edge of the forecast area. This is in line with the latest short
term hires models rap/hrrr/dlh WRF. This is also in agreement with
the latest radar trends in the Dakotas. Rest of the forecast on


Short term...(this evening through sunday)
issued at 341 PM CST Sat Feb 13 2016

Short term adjustments for slower timing of onset of snow
overnight/Sunday. Latest high resolution guidance showing good
agreement the 800/500hpa trough holds off on moving into western
Minnesota until Sunday morning...slowly tracking across north
central Minnesota Sunday afternoon. The bulk of the snowfall
associated with this system will be found over northeast South
Dakota and west central Minnesota overnight into Sunday
morning...with weak forcing and light snowfall amounts of generally
around an inch over the north central Minnesota zones through Sunday
afternoon. As winds switch out of the south overnight...there is a
chance for lake effect clouds/light snow to drift onshore in the
Grand Marais/Grand Portage area. Have introduced small probability of precipitation to
account for this.

Due to the slower timing of the clouds/snow overnight...have also
lowered temperatures accordingly. Current msas analysis shows the
surface ridge axis centered over the Western Lake Superior region. As
the ridge gradually shifts east this evening...there will be a period
of clear skies and light winds to support strong radiational cooling
and rapidly falling temperatures into the negative teens. The lowest
temperatures overnight will be found across the Iron Range and over
northern Wisconsin.

Long term...(sunday night through saturday)
issued at 341 PM CST Sat Feb 13 2016

By Sunday evening the surface low pressure trough should be moving across
northern Minnesota with a band of snow ahead of it...while most of the
snow will be done by Monday afternoon...the Northland will remain
under cyclonic flow from the upper low north of the region. The low
will bring a series of S/waves across the region...with will result in
some lingering snow showers Monday into Tuesday night.

There will be a cool down after this early week system...but not
nearly as cold as we have seen with 800 mb temperatures to be -12c to -16c.
With this cold air and northwest flow...could see some lake effect snow
over the South Shore...but the Delta t's will not be extreme. The
surface high that will be over the region after monday's snow will
move away from the Northland on Wednesday and this will result in
a very strong return flow beginning Wednesday night. Also by
Thursday another long wave trough will made landfall on the West
Coast and move across the U.S. This system will bring US very warm
temperatures but also chances of mixed precipitation late in the week. By
Friday the extended models have the same idea of a 500 mb closed
low over the north...but their locations are vastly different so
this likely be resolved later next week.


Aviation...(for the 06z tafs through 06z Sunday night)
issued at 1137 PM CST Sat Feb 13 2016

Expecting VFR conditions to gradually deteriorate to MVFR/IFR as
a warm front lifts through the northern plains tonight and into
western Minnesota by Sunday afternoon. Late on Sunday the front
will lift into central portions of Minnesota and the northern half
of Wisconsin. This will gradually lower ceilings to the MVFR range.
Snow will spread into all terminals as the period progresses
which will bring visby reduction. Think that most visby reduction
will remain in the MVFR range...but gfslamp has hinted at IFR
visby at all locations. Felt most confident to include IFR visby
between 20z and 03z at kbrd and kinl as they are closest to the
strongest forcing from the front.


Preliminary point temps/pops...
dlh -9 16 11 28 / 0 50 60 20
inl -12 17 12 27 / 10 60 60 30
brd -1 19 12 30 / 20 60 40 20
hyr -13 17 10 29 / 0 50 50 20
asx -12 19 11 29 / 0 30 30 20


Dlh watches/warnings/advisories...


short term...graning
long term...clc

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