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Area forecast discussion 
National Weather Service Duluth Minnesota
1248 am CDT Monday Apr 21 2014

issued at 826 PM CDT sun Apr 20 2014

A lake breeze is moving inland from Lake Superior at this moment.
Surface wind has switched to NE for a brief time..but then gone light.
Meanwhile...a cold front was moving into NE ND with some cirrus ahead of
the front. In the vicinity of the front in ND...middle clouds have
formed. Fairly dry below 10k feet and no rain being reported
underneath increasing radar returns in NE ND. Have dialed back on
the probability of precipitation to just over a portion of Koochiching County after
midnight. This is supported by latest hrrr/rap/local WRF model
runs. Rest of the forecast on track.

Update issued at 532 PM CDT sun Apr 20 2014

Latest short term hires models indicate the rain will stay well S
of Price County WI and have removed the mention. Made some other
minor adjustments.


issued at 250 PM CDT sun Apr 20 2014

An elongated surface ridge stretches from ctrl Manitoba across the northern
County Warning Area and over Lake Superior. Dry air mass has allowed sunny skies to
cover most of the region. The exception is the southern edge of Price
County where clouds associated with the southern frontal boundary are moving
east-northeast. As or early afternoon temperatures have soared into the low 70s in a few
spots otherwise 60s are more common at inland locations with 50s and
a few 40s close to Lake Superior.


Short term...(this evening through monday)
issued at 250 PM CDT sun Apr 20 2014

Tonight...a westerly middle level flow will keep the progressive nature
of the pattern in place. Two features of note are the old frontal
boundary located over southern Minnesota and the approaching surface/middle level low over
ND. Should see radiational cooling for the first part of the
evening before warm advection regime develops from west to east as
ND system heads our way. The frontal boundary south of the County Warning Area will
push north overnight with increasing clouds and some light rain
possible over sctrl/southeastern County Warning Area. Br/fog is possible over southern County Warning Area in
advance of the warm front. Meanwhile the frontal system in ND
will push into the northwestern County Warning Area after midnight with light precipitation.

Tomorrow...very fast movement of the surface/middle level features so expect
any light precipitation to quickly shift east across the region during the
morning hours. Main distinguishing weather element will be the gusty
winds developing behind the cold frontal passage. Temperatures may show a non
diurnal trend based on timing of front over Minnesota zones. Temperatures will be
about 5 to 10 degrees lower than Sunday however still above climatology in
most of the County Warning Area.

Long term...(monday night through sunday)
issued at 250 PM CDT sun Apr 20 2014

Main concern for long term is the system affecting the region
Wednesday through Friday. Nigh pressure will dominate the weather
on Tuesday with partly to mostly sunny skies. It will be a remain
dry with near normal temperatures. Relative humidities will be in
the middle 30s across the western and southern areas.

The storms system will start to affect the forecast area on
Wednesday. It is a slow moving system with the models somewhat
different on the location of the low but both suggest ptype will be
all rain Wednesday through Thursday evening. The GFS has the center
in southern Minnesota while the European model (ecmwf) has the center in western Iowa at 12z
Thursday. The center of the low will be near the WI/Upper Michigan border on
the GFS while the European model (ecmwf) has the center around eau. Will use a
compromise between the models for the solution. As indicated by the
previous shift...the models still indicates cape along with seep
middle-level lapse rates Wednesday night and Thursday so will keep
thunderstorms in current grids. Colder air will push into the
forecast Thursday night as the low pulls off to the east. There will
be a change over to a rain/snow mixture with sleet possible.
Amounts should be light as this time. With the differences in the
models..the timing and ptype could change in the coming runs.
Colder than normal temperatures will contribute into the weekend.


Aviation...(for the 06z tafs through 06z Monday night)
issued at 1248 am CDT Monday Apr 21 2014

Surface low and associated cool front has advanced eastward into
western Minnesota late this evening...and scattered showers have
been reported over portions of northwestern Minnesota. The front
should pass through the Minnesota terminals before 12z and through hyr
mid-morning. The best chance of showers will affect
hib...inl...and dlh after frontal passage. Kept a mention of
vcsh at brd and hyr. Clouds are streaming northward over
northwestern Wisconsin and will affect hyr overnight. Current
thinking is that mainly middle-level clouds will affect the
terminal. However...sites farther south have reported ceilings as low
as 800 feet within the last hour. Winds will be quite breezy on
Monday and have maintained higher sustained winds and gusts from
previous forecast.


Preliminary point temps/pops...
dlh 33 50 32 47 / 0 0 0 40
inl 31 50 32 52 / 10 0 10 40
brd 34 56 37 52 / 0 0 10 50
hyr 33 52 31 52 / 0 0 0 40
asx 33 47 31 50 / 0 0 0 30


Dlh watches/warnings/advisories...


short term...Cannon
long term...Stewart