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Area forecast discussion 
National Weather Service Duluth Minnesota
316 am CDT Monday Apr 27 2015

Short term...(today through Tuesday afternoon)
issued at 315 am CDT Monday Apr 27 2015

Main concerns in the short term are focused around the relatively
warm and very dry conditions expected today...with cloud cover
increasing in the late afternoon and evening ahead of a weak cold
front forecast to move across the region tonight through Tuesday
with light rain showers possible.

High pressure at the surface combined with an upper level ridge
and a very dry air mass will continue to dominate the region most
of today with quiet weather. Temperatures will be able to warm
into the 60s and lower 70s with plenty of sun. Winds will remain
light in the morning...but become occasionally breezy in the
afternoon as the surface ridge moves eastward and a weak pressure gradient sets
up over NE Minnesota.

Cloud cover will increase from northwest to southeast in the late afternoon and
especially evening hours today as a weak cold front and
associated upper short wave move in across northern Minnesota. Latest model guidance
has definitely backed off on rainfall amounts with around or less
than a tenth of an inch possible. The front appears to wash out as
it moves eastward into the Western Lake Superior/northern WI area...which will
allow rain chances to diminish through the afternoon. High
pressure begins to build back in behind the departing trough late
in the day Tuesday over northern Minnesota.

Temperatures Tuesday morning will remain mild in Minnesota with
cloud cover and warm air advection in the middle levels keeping lows in the lower
40s. However to the east in Wisconsin...less cloud cover and light
winds will allow temperatures to fall into the upper 20s and 30s.
During the afternoon...temperatures will warm into the 60s across
the entire area with slightly cooler conditions near ls.

Long term...(tuesday night through sunday)
issued at 315 am CDT Monday Apr 27 2015

Upper level and surface ridging are building in the forecast area
Tuesday night. Even though a closed upper low drops southward through
Eastern Lake Superior...atmosphere is very dry and expect no precipitation
and only some cloud cover as ridging remains through Wednesday. The
closed upper low departs Wednesday night allowing the upper ridging
to build back in. The ridging prevails on Thursday. Model
differences begin to reveal themselves Thursday night. The GFS
maintains the ridging while the Gem/European model (ecmwf) flatten the upper ridge
allowing short wave energy to cross through the region. Have ignored
the GFS. At the surface...a front moves to the western edge of the
forecast area by 12z Friday. Used a compromise of the Gem/European model (ecmwf) for
probability of precipitation Thursday night. The GFS is about 12 hours behind the other
models on Friday with its handling of the front. The European model (ecmwf)/Gem push
the front to the east. A compromise of the solutions results in probability of precipitation
over the area. The GFS finally moves the front east of the area
Friday night. All models have a quasi zonal flow setting up over the
region Friday night. This fast flow will allow a short wave to clip
the Canadian border. A blend of models was used as a result for probability of precipitation
Friday night. Next opportunity for precipitation comes Saturday night and
Sunday as short waves move along the Canadian border in the zonal
flow. Enough instability is found on Sunday and have added a mention
of thunderstorms to the southern half of the forecast area.


Aviation...(for the 06z tafs through 06z Monday night)
issued at 1219 am CDT Monday Apr 27 2015

VFR conditions are expected with light winds through much of the
period. Some gusts of 10 to 15 knots will develop Monday afternoon
with deeper mixing. A cold front will spread some middle clouds to kinl
late in the period.


Preliminary point temps/pops...
dlh 64 37 64 40 / 0 0 20 0
inl 69 43 63 36 / 0 30 10 0
brd 70 42 65 39 / 0 20 20 0
hyr 64 33 65 38 / 0 0 20 0
asx 57 30 64 36 / 0 0 20 0


Dlh watches/warnings/advisories...


Short term...bjt
long term...gsf

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