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Area forecast discussion...updated 
National Weather Service Duluth Minnesota
656 PM CDT sun Aug 2 2015

issued at 656 PM CDT sun Aug 2 2015

Updated aviation discussion for 00z taf issuance below.


Short term...(this evening through monday)
issued at 244 PM CDT sun Aug 2 2015

A cold front has moved through the rest of our northwest Wisconsin
zones as of 20z. However...a shortwave was dropping southeast
through the region. The shortwave as well as residual outflow
boundaries from earlier convection continued to aid in producing showers
and thunderstorms from the Iron Range into northwest Wisconsin.
Although the better risk for severe storms has shifted south of
the Northland...MLCAPE of 1500-2000j/kg and 50kt of deep layer
shear over northwest Wisconsin is still present. There could
still be a strong storm mainly southeast of a Hayward to Ironwood
line through about 6 PM.

The showers and storms should exit the Northland early this
evening...then as colder air continues south and moisture
increases there could be some showers that form over the border

Clouds will continue to drop south on Monday with some showers
possible in spots under these colder temperatures aloft. Highs
will only be in the middle 60s far north and the lower to middle 70s
across our southern zones.

Long term...(monday night through sunday)
issued at 244 PM CDT sun Aug 2 2015

Summary...the Northland will be in a cool northwest flow pattern for the
middle of the week...keeping the Northland slightly cooler than
normal. Temperatures might rebound back to normal by late this week.
Thunderstorms are possible later in the week.

Tuesday...surface high pressure will begin to move into the
Northland. The cool northwest flow aloft...though...will help develop
scattered/broken cumulus clouds by the early afternoon. The cloud cover will
further limit daytime heating...especially over The Arrowhead.
Showers are possible over The Arrowhead and in the Ashland and Iron
County areas of northwest Wisconsin. Leaned on the cooler GFS for high
temperatures...with highs primarily in the upper 60s and low 70s.

Wednesday...surface high pressure should help keep the Northland dry
and a bit sunnier than Tuesday. Temperatures will be a bit warmer in
the lower 70s. Cut back on precipitation chances based on the drier 12z
GFS/ECMWF/Gem runs.

Late Wednesday/Thursday...there is some uncertainty as to precipitation
chances. The GFS is indicating surface high pressure will keep the
Northland dry. However...the European model (ecmwf) and Gem are indicating a
potential storm complex developing east of an upper level ridge and
near the ND/MN/Manitoba/Ontario border region Wednesday night into
Thursday morning...potentially affecting the northwest forecast area. Kept
the forecast mostly dry for now since the upper level ridge would
likely help prevent much from developing...but will need to keep an
eye on subsequent model trends. There are low chances of precipitation across
the far southern forecast area for Wednesday night and
Thursday...but might be able to remove this completely with
subsequent forecasts. The low chances are to account for the wave
that will likely eject into the plains during the Wednesday/Thursday
time frame...but the models are continuing to trend this feature
farther south and at an earlier time. The latest models primarily
indicate this wave moving through southern Minnesota/Iowa...or even
farther south...on Wednesday. Need to maintain some low precipitation chances
until confidence increases on the sooner and more southern track.

Friday/Saturday...warm and more humid southerly flow will likely
develop across the Northland as low pressure approaches from the
west. Showers and storms are possible. Temperatures might return to
near normal with highs in the middle 70s.


Aviation...(for the 00z tafs through 00z Monday evening)
issued at 656 PM CDT sun Aug 2 2015

Broad northwest to west-northwest surface flow will persist through this taf period
as high pressure continues to build southward into the plains..and
the western Great Lakes region remains within the fairly tight
gradient between the ridge to our west and deepening low pressure
over eastern Ontario and Quebec. Winds should exhibit a tendency
to weaken and veer to a slightly more west-northwest direction overnight
tonight..with a temporary cessation of gustiness around sunset.
However..winds should strengthen and back by 10-20 degrees during
the 14-16z time frame Monday morning..with gusts in the 17-22kt
range developing again tomorrow.

Expansive stratocumulus deck currently covering much of northwest
Ontario will gradually slide east-southeastward overnight and Monday..and will
likely spread a period of MVFR conditions into kinl and perhaps
khib/kdlh. As colder temperatures aloft advect in from the north on
Monday..this will act to steepen low level lapse rates even in
the absence of full surface heating..likely resulting in scattered
showers and a few thunderstorms the last 6 hours of this taf


Preliminary point temps/pops...
dlh 53 71 51 70 / 0 20 10 10
inl 49 65 45 67 / 10 20 0 10
brd 50 76 50 75 / 0 0 0 0
hyr 50 72 48 70 / 10 20 10 10
asx 52 73 52 68 / 10 10 0 20


Dlh watches/warnings/advisories...


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