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Area forecast discussion 
National Weather Service Duluth Minnesota
545 PM CST Wednesday Nov 26 2014

issued at 539 PM CST Wednesday Nov 26 2014

Updated for new aviation discussion below.


Short term...(this evening through thursday)
issued at 255 PM CST Wednesday Nov 26 2014

Main concern for short term is lake effect snow along South Shore.

Current surface analysis indicates mainly clear to partly cloudy
skies across NE Minnesota to cloud skies with light snow across northwest WI.
For the rest of the afternoon...the light snow will end across NE
Minnesota and most of northwest WI except on the South Shore of Lake Superior.
In northwest WI in that area...lake effect snow showers have developed.
Models indicate winds will continue from the north to northwest through
tonight into Thursday morning. 850 mb temperatures are already around -10
and will drop to around -15 by 06z. Also...moisture will be good
tonight. As indicated by previous shift...the higher resolution
models still show the decent snowfall amounts with 3-6 inches from
Douglas County to Ashland with higher amounts in Iron County. Will
keep current headlines unchanged.

For the rest of the forecast area...the coldest air of the fall
will continue to push into the region. Lows tonight will be below
zero in most areas except along the lake. Skies will be generally
partly to mostly sunny Thursday with highs only in the single
figures to teens above zero.

Long term...(thursday night through wednesday)
issued at 255 PM CST Wednesday Nov 26 2014

A warm front will begin to move into the western edge of the forecast area by
06z Friday. Warm air advection/isentropic lift and low level convergence will get
the light snow going west of Highway 169 and west of Highway 38 in NE Minnesota. To the east
of this area...surface ridge axis/dry air will prevail. After 06z...the
warm front continues its trek across the forecast area with light snow
spreading over the rest of the forecast area. Highest probability of precipitation will be in the vicinity
of the front. Differences in model quantitative precipitation forecast so will use a model blend.
This leads to a band of higher snow amounts over portions of the
southern half of the forecast area. The warm front appears to stall out over northwest
WI Friday morning. Meanwhile...short wave energy slides into the
area on fast northwest flow aloft. This places the higher snow amounts in
northwest WI to near the twin ports. Model differences Friday afternoon are
present with the GFS keeping the front nearly stationary while the
European model (ecmwf) attempts to lift it northward to near the international border. Will
keep some probability of precipitation across the forecast area as a blend of solutions. Model
differences become a bit large Friday night through through Saturday
night before coming to a better agreement Sunday night. As a
result...will carry probability of precipitation over the much of the northern portion of
the forecast area through Sunday where best forcing/moisture will be found. On
Sunday night...a west-northwest flow over Lake Superior will generate some snow
showers for a few hours before turning to the west and ending. Have
some small probability of precipitation to account for this. Elsewhere...high pressure will
be building over the forecast area. This will linger through Monday. Warm air advection will
begin Monday night ahead of the next surface low to move along the
Canadian border. A cold front will be dragged through the forecast area and
have some probability of precipitation for expected light snow.


Aviation...(for the 00z tafs through 00z Thursday evening)
issued at 539 PM CST Wednesday Nov 26 2014

Skies will clear from west to east across the high
pressure builds into the region. The clouds will linger longest in
northwestern Wisconsin...around khyr...where some light snow
showers will prevail as well.


Preliminary point temps/pops...
dlh -3 9 4 19 / 20 0 80 80
inl -11 8 0 17 / 0 0 50 30
brd -6 9 6 21 / 0 0 80 40
hyr 0 11 1 22 / 60 0 80 80
asx 6 13 2 22 / 80 50 50 80


Dlh watches/warnings/advisories...
WI...lake effect snow warning until noon CST Thursday for wiz003-004.

Lake effect Snow Advisory until 3 am CST Thursday for wiz001-002.

Ls...Small Craft Advisory until 4 am CST Thursday for lsz121-147-148.



short term...Stewart
long term...gsf

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