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Area forecast discussion 
National Weather Service Duluth Minnesota
320 PM CDT Friday Aug 29 2014

Short term...(this evening through saturday)
issued at 322 PM CDT Friday Aug 29 2014

At 315pm...there was an upper level trough and potent shortwave
over the Central Plains. There was an associated surface trough
over northern Minnesota and northwest Manitoba. A warm front stretched
across west central and central Wisconsin. Much of the Northland
had cloudy skies...but there was some clearing moving into the far
southeast forecast area due to clearer skies farther south in the warm
sector. Showers and storms were moving through the
Northland...mainly the eastern and southern forecast area.

Through this evening...the upper level trough in the Central
Plains will lift towards Wisconsin. The surface trough will
continue moving east through the forecast area...and the warm
front in Wisconsin will continue moving north. The warm southerly
flow and moisture transport ahead of the surface trough will
continue to bring showers and storms into northwest Wisconsin. The
precipitable water values are around 1.8 inches...so heavy rain is
possible with any thunderstorms...especially if the storms train.
There is a very low risk of gusty winds with thunderstorms in our
far southeast forecast area through this evening. The approaching warm
front and clearing could cause enough heating to cause enough
instability to result in some strong storms.

Tonight...the precipitation chances will generally decrease overnight as
the moisture transport shifts farther east. A shortwave in western
North Dakota this afternoon could bring isolated showers to the SW
forecast area late tonight. The combination of light wind and high
moisture could result in patchy fog for parts of the forecast
area.

Saturday...high pressure will generally keep the forecast area
dry...but there could be lingering showers in the far southeast forecast
area...as well as isolated showers and storms during the afternoon
south of Highway 2 due to weak convergence near a trailing trough.
The morning looks cloudy...but there will likely be scattering
during the afternoon. High temperatures should be in the upper 60s
and low 70s.

Long term...(saturday night through friday)
issued at 322 PM CDT Friday Aug 29 2014

Overall pattern remains similar in featuring a progressive flow
aloft across the northern Continental U.S. This period. After some initial
collapse of middle level heights early in the period a trend towards a
large building ridge occurs from the southern rockies into the middle
Atlantic. While too early to tell this may place parts of the
region within a favorable corridor of high precipitable waters and potential
mesoscale convective system/mesoscale convective complex development. The first round of precipitation will move
across the Northland Sunday into Monday. A few days of generally
benign weather should develop from late Monday into Thursday. The area
will be influenced by a passing surface high that moves from the Central
Plains into the Ohio Valley. Although some probability of precipitation are currently in
the forecast Tuesday the moisture/lift is limited and later shifts may
be able to reduce/eliminate what is currently forecast. The next
credible chance for organized lift and moisture transport will be late
in the week as a frontal boundary arrives from the northern plains. By that
time the area of forcing should have significant precipitable waters to act
upon.

&&

Aviation...(for the 18z tafs through 18z Saturday afternoon)
issued at 1242 PM CDT Friday Aug 29 2014

Warm frontal showers and storms will continue near khyr through
afternoon/early evening while slow moving cold front makes its way
towards western terminals. Although a possible brief period of low
MVFR may develop at some sites...LIFR to IFR conditions will
prevail at most locations through afternoon ahead of front. A
period of br/fog is possible with frontal boundary and its associated low
level moist axis this evening and early Saturday morning. Surface press
gradient behind front should begin to mix out lower level clouds and
br/fog by 12z.

&&

Preliminary point temps/pops...
dlh 58 67 54 74 / 20 10 10 40
inl 52 71 52 73 / 30 0 10 70
brd 59 72 58 78 / 20 20 10 70
hyr 60 72 55 79 / 60 20 10 20
asx 58 68 53 78 / 70 20 10 10

&&

Dlh watches/warnings/advisories...
Minnesota...none.
WI...none.
Ls...none.
&&

$$

Short term...grochocinski
long term...Cannon
aviation...Cannon

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