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Area forecast discussion 
National Weather Service Duluth Minnesota
808 PM CDT Tuesday Jun 30 2015

Update...
issued at 808 PM CDT Tuesday Jun 30 2015

Allowed the beach hazard to expire on time. NE wind continues
along the head of Lake Superior...but have diminished
as well as waves. Rest of the forecast is on track.

&&

Short term...(this evening through wednesday)
issued at 258 PM CDT Tuesday Jun 30 2015

High pressure and cool air aloft brought a mostly sunny but cool
day for the end of June. Temperatures struggled to reach 70
across the Minnesota arrowhead and northern Wisconsin this
afternoon...with readings in the low 70s across the Brainerd lakes
area. Light winds...in combination with the cool and dry air
mass...will allow for overnight lows to fall into the 40s across
much of the Northland. The exception will be in the Brainerd lakes
region where more clouds will be found...along with higher dew
points...allowing temperatures to hold in the 50s.

The 850 mb temperatures will be on the increase Wednesday...along with winds
gradually turning out of the south as a short wave dives across
the Dakotas and into SW Minnesota. Temperatures will still be on
the cool side...with highs in the low 70s. However...an onshore
flow will keep readings cooler...in the 50s to 60s...along the
shores of Lake Superior. Have kept the forecast dry for
Wednesday at this time. However...the latest GFS/NAM suggest the
elongated area of vorticity that will trigger showers may drift
further east into north central Minnesota. However...suspect some
of this may be contaminated by convective feedback and the bulk of
the precipitation will remain across the SW portion of Minnesota.

Long term...(wednesday night through tuesday)
issued at 258 PM CDT Tuesday Jun 30 2015

A transitional pattern over the weekend as upper flow changes from
late this week to southwesterly by early next week. With a
transitional pattern expected there are inherent uncertainties with a
pretty wide range of model solutions...but overall fairly confident
in a strong cold front late sun into into Monday. Ahead of this cold
front temperatures will be fairly mild...with more seasonable temperatures behind
it. There are chances for precipitation nearly every day...though generally
low chances until the cold front approaches late in the weekend.

On the synoptic scale a ridge over The Rockies will weaken through
the rest of the work weak causing the jet stream to dip down and
bring a series of weak middle-level disturbances our way. Late in the
weekend a stronger upper low will travel down across the southern
tier of Canada causing a surface low and accompanying cold front to move
through. Global guidance still has some broad disagreements...with
the Canadian and European model (ecmwf) depicting a frontal passage Sunday afternoon
into Sunday night while the GFS holds off until late Sunday night
into Monday. If this earlier progression turns out to be a good
solution there will be a chance for strong to severe thunderstorms
due to sufficient instability and shear. Too far out to pin down
more details...but at this point signs point towards a severe
thunderstorm possibility.

&&

Aviation...(for the 00z tafs through 00z Wednesday evening)
issued at 614 PM CDT Tuesday Jun 30 2015

With high pressure nearby...look for VFR through the forecast
period.



&&

Preliminary point temps/pops...
dlh 47 68 51 76 / 0 0 10 10
inl 45 75 55 78 / 10 10 10 20
brd 52 73 53 78 / 10 10 10 10
hyr 43 70 48 79 / 0 0 0 10
asx 43 67 47 76 / 0 0 0 10

&&

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

$$

Update...gsf
short term...graning
long term...jjm
aviation...gsf

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