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Area forecast discussion 
National Weather Service Duluth Minnesota
1225 am CDT Friday Sep 19 2014

Update...
issued at 1222 am CDT Friday Sep 19 2014

Updated for the new 06z aviation discussion below.

&&

Short term...(this evening through friday)
issued at 317 PM CDT Thursday Sep 18 2014

Concern for short term is rain tonight and Friday

Current surface analysis indicates mainly clear skies across the
western portions of the forecast area with cloudy skies covering
the twin ports...arrowhead...and northwest WI. The clouds will decrease
this evening before increasing after midnight ahead of a frontal
system. Southerly flow and low level jet will increase the moisture into
the forecast area overnight. There will be a possibility of
showers across the Borderland overnight with a shortwave moving
through southern Canada.

On Friday...the front will extend from the international border SW
into western Minnesota. Rain will spread west to east across the forecast
area in the morning. There is some cape (500-700) with the precipitation
so will have a chance thunderstorms with the rain. As indicated by the
previous shift...if any storms develop...it will probably be in
the southern County Warning Area counties.

Long term...(friday night through thursday)
issued at 317 PM CDT Thursday Sep 18 2014

The cold front will move through the forecast area Friday night. Showers and
thunderstorms will accompany the front. On Saturday...a sharpening
upper level trough moves into Minnesota. Some showers are possible in the
morning over the northern third of the area. Instability increases
in the afternoon as another cold front moves through the forecast area. Showers
and isolated thunderstorms are expected. As the cold front exits
Saturday night...embedded pieces of short wave energy will affect
the forecast area with some showers...especially over the northern third of the
forecast area. High pressure builds into the rest of the area Saturday night.
Last piece of short wave energy affects the area around Western Lake
Superior Sunday and have some low probability of precipitation. The high prevails over the
rest of the forecast area. High pressure then dominates the weather through
Tuesday night. By Wednesday...the high is moving off to the east and a
return flow sets up. Warm air advection/isentropic lift may be enough to bring a
few showers to the western edge of the area. Have small probability of precipitation in
place. Temperatures will be above normal through the period.

&&

Aviation...(for the 06z tafs through 06z Friday night)
issued at 1222 am CDT Friday Sep 19 2014

There was widespread LIFR/IFR ceilings over northeast
Minnesota...including the kdlh/khib/kinl areas. The kbrd and khyr
areas had VFR conditions. The Northland had southeast winds around 10 knots.

The winds will increase and become southerly overnight and Friday
morning. A strong south-southwest low level jet...about 40 to 50 knots...will
develop overnight. The forecasts include low level wind shear through the night.
While there may be some gusts later tonight...do not believe the
boundary layer will be sufficiently mixed to drop the low level wind shear until
dawn.

Gusty southerly winds will develop over the region Friday as the
boundary layer mixes out with daytime heating. The strongest winds
may be over northwest Wisconsin...including khyr which could see gusts
approach 30 knots. There will be increasing low level
saturation...which will likely result in low ceilings and a transition
towards MVFR ceilings. An approaching front in the northern plains
will bring showers...maybe storms...through the Northland
tomorrow. Confidence on the development...let out alone
timing...of storms is low. Therefore left out storms in the
forecast for now. The widespread MVFR ceilings will likely continue
through the early Friday evening.

&&

Preliminary point temps/pops...
dlh 59 68 49 63 / 30 50 10 20
inl 54 65 47 61 / 60 60 70 10
brd 58 71 49 67 / 10 40 10 10
hyr 61 71 49 64 / 30 40 10 20
asx 60 69 50 60 / 30 50 10 30

&&

Dlh watches/warnings/advisories...
Minnesota...none.
WI...none.
Ls...Small Craft Advisory from 7 am this morning to 4 PM CDT this
afternoon for lsz140.

&&

$$

Short term...Stewart
long term...gsf
aviation...grochocinski/mclovin

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