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Area forecast discussion 
National Weather Service Duluth Minnesota
622 PM CDT Friday Aug 1 2014

Short term...(this evening through saturday)
issued at 315 PM CDT Friday Aug 1 2014

At 315pm/2015z...there was an upper level low over western Quebec.
Its associated upper level trough extended through the upper
Midwest to the southern United States. Weak high pressure was
centered over Central Lake Superior. There was a shortwave over northwest
Wisconsin and embedded in the upper level trough...and it was
moving to the south-southeast. Much of the Northland had partly cloudy skies
and very light wind. There was a lake breeze due to easterly winds
over Western Lake Superior...and the lake breeze had made it well
inland over The Arrowhead. Much of the western and southern
forecast area had developed 500 to 1000 j/kg of mixed layer cape.
There were isolated to scattered showers and weak storms...mostly
over the SW and south central forecast area. There were a few
storms near the twin ports. Temperatures were in the middle 70s to
low 80s with dew point temperatures in the 50s to low 60s.

Through early this evening...there will continue to be isolated to
scattered showers and storms over parts of the forecast area until
we get closer to sunset. Some storms could produce brief small

Tonight...there will be clearing over the Northland. The
combination of the clear skies and very light wind will result in
overnight lows in the lower 50s. The higher dewpoint temperatures
compared to last night will make conditions more favorable for fog
tonight. I added fog over Lake of the North
Shore...and the southern forecast area. This was the area most
likely to get fog based on model surface condensation pressure
deficits. will be another warm day. Light SW to west winds will
develop ahead of a prefrontal trough that will move into NE
Minnesota during the day...and with an approaching cool front
dropping southeast in Canada. The models suggest there could be isolated
showers and storms during the afternoon over the Northland. Mixed
layer cape could build to 500 to 1000 j/kg again. Wind shear looks
to be the threat of any strong storms is low. There
will also be increasing chances of showers and storms over far
northern Minnesota during the afternoon due to the approaching
cold front.

Long term...(saturday night through friday)
issued at 315 PM CDT Friday Aug 1 2014

Have kept high chance probability of precipitation across the forecast area Sat night/Sunday
as a weak short wave with surface reflection cold front drops over
the region. The showers and storms associated with the front will
linger into Sunday night over the Wisconsin zones. Models are in
good agreement that middle level ridging with a broad area of surface high
pressure settles over the Borderland/western lakes Superior region
into next week. At this time...the large Canadian high and dry air
looks to take hold of northern Minnesota/Western Lake Superior and keep the
forecast mainly dry with seasonable temperatures through the upcoming
week. Meanwhile...a baroclinic zone over southern Minnesota/Iowa
strengthens into a warm front...becoming the focus for showers and
thunderstorms. Have trended probability of precipitation in the extended periods down as
the main corridor of precipitation looks to remain south of the dlh County Warning Area.

Have lowered overnight temperatures Monday night through Thursday night
as lower dew points/clearing/light winds associated with the
high will allow for radiational cooling. The coolest readings will
be across the Borderland/arrowhead region.


Aviation...(for the 00z tafs through 00z Saturday evening)
issued at 622 PM CDT Friday Aug 1 2014

A couple of thunderstorms in the vicinity of dlh through 02z. Loss of
sun will lead to the storms diminishing. Otherwise...VFR. Left in
the mention of patchy fog for now.


Preliminary point temps/pops...
dlh 55 80 56 74 / 10 20 50 40
inl 51 80 53 77 / 0 40 40 10
brd 57 83 58 78 / 20 20 50 40
hyr 54 81 55 79 / 20 20 50 50
asx 52 78 55 74 / 10 20 50 50


Dlh watches/warnings/advisories...


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

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