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Area forecast discussion 
National Weather Service Duluth Minnesota
529 PM CST sun Feb 14 2016

Short term...(this evening through monday)
issued at 328 PM CST sun Feb 14 2016

Only minor adjustments to short term forecast mainly for timing.
Current radar imagery shows a well defined area of moderate to
brief heavy snow in a region of strong forcing and upper level
divergence ahead of middle level trough/vorticity maximum tracking over
northeast Minnesota. The area of forcing and associated snow will shift
east over the Minnesota arrowhead and northern Wisconsin zones
through the evening...ending for locations in north central
Minnesota by midnight.

Snowfall totals of 1 to 2 inches will be common across the
Northland through the morning. Locally higher amounts of 2 to 4
inches will be found along the North Shore of Lake
Superior...mainly in the Lutsen to Grand Marais and Grand Portage
corridor...where on shore winds of 15 to 20 knots will promote
lake enhancement.

The western Great Lakes region will be in a broad cyclonic flow
with weak warm air advection on Monday. Latest bufr soundings
suggest a strong inversion keeps persistent low clouds through
the day. Have kept slight chance probability of precipitation along the Borderland...with
a dry forecast elsewhere...although flurries/drizzle can not be
ruled out due to the low level moisture and 500hpa temperatures of
negative 30c.

Long term...(monday night through sunday)
issued at 328 PM CST sun Feb 14 2016

The main concern for the long term is the possibility of mixed
precipitation Thursday and Friday. There also could be some light
snow on Tuesday.

A quick moving shortwave will move through western Minnesota Monday night
into central Iowa by Tuesday morning. The southerly flow out ahead
of the wave will push little moisture into the forecast. Will keep
the chance probability of precipitation in the grids for Monday night through Tuesday night.
Will keep lingering snow showers across the Southern Lake Superior
snow belt through Wednesday before ending Wednesday evening as the
wind direction shifts across the region. An area of high pressure
will build into the forecast area on Wednesday. Temperatures will cool
off into the 230s on Wednesday but warm up into the 30s on Thursday.

A strong low pressure will affect the forecast region Thursday
afternoon through early Saturday morning. The center will move from
South Dakota Thursday night to west central Minnesota by Friday morning to the
northern Great Lakes by Friday night. As indicated by the previous
shift...the European model (ecmwf) is still a little faster and warmer than the GFS.
Also...with the possibility of wame3r air across the region...there
is a possibility of mixed wintry precipitation across the
forecast area. Will keep the mixed freezing/frozen ptype in the
grids Thursday night through Friday evening with all changing to
snow by Friday night as colder air moves into the region. There
will be some accumulations Friday night and Saturday but it is too
early to determine the amounts.


Aviation...(for the 00z tafs through 00z Monday evening)
issued at 529 PM CST sun Feb 14 2016

An area of light snow was moving through the terminals at the
start of this forecast period. Mainly IFR/MVFR ceilings with LIFR
visibilities/ceilings where moderate snow is expected. The snow will diminish
from west to east overnight leaving flurries and MVFR ceilings behind.
These conditions will persist through the end of the forecast.


Preliminary point temps/pops...
dlh 13 29 20 25 / 90 10 20 20
inl 13 29 14 19 / 90 20 20 10
brd 14 32 19 25 / 80 10 30 20
hyr 12 29 20 31 / 80 10 20 20
asx 13 30 22 32 / 60 10 20 40


Dlh watches/warnings/advisories...


Short term...graning
long term...graning

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