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Area forecast discussion 
National Weather Service Twin Cities/Chanhassen Minnesota
351 am CDT Tuesday Jul 29 2014

Short term...(today and tonight)
issued at 350 am CDT Tuesday Jul 29 2014

Not a big change in the weather from yesterday...with the exception
of a few less morning clouds and temperatures climbing a couple
degrees higher today. Expect highs to top out from 75 to 80
degrees...with northwest winds around 10 miles per hour dominating for another
day. Today/S diurnally-driven isolated to scattered shower
activity...sponsored by faint middle level shortwave energy embedded in
the western periphery of the Hudson Bay expected to occur
over west central WI today...possibly sneaking as far west as the
Interstate 35 corridor this afternoon.

Tonight should bring clearing skies and winds decreasing below 5
miles per hour...with another night with lows from 50 to 60 degrees.

Long term...(wednesday through monday)
issued at 350 am CDT Tuesday Jul 29 2014

There are only so many different ways to describe this weeks weather
pattern over the upper Midwest...and it appears we are approaching
that limit. Northwest flow...Rocky Mountain ridging and James Bay
low continue to be the dominate upper level features...with
occasional shortwaves bringing precipitation chances across the eastern
County Warning Area.

The best chance for precipitation at this time is Thursday afternoon and
overnight. Based on the timing of the shortwave the Thursday night
period would be most favorable...and indeed the model generated quantitative precipitation forecast
replicates this. However...the boundary layer will quickly stabilize
overnight...and with no low level jet to work with find it hard to
believe that the paltry upper level forcing within the weak flow
regime will be enough to produce anything more than an isolated
shower or thunderstorm.

Sunday night the GFS 29.00 brings a shortwave across the
international border which would support a better chance of
probability of precipitation...but the European model (ecmwf) shears out this wave in the confluent upper
level flow. Did not make significant changes from the model
guidance...but 30 percent probability of precipitation seem a bit overdone...and may need to
scale them back as we get closer to the upcoming weekend.
Temperatures will remain seasonable with light winds.


Aviation...(for the 06z tafs through 06z Tuesday night)
issued at 1059 PM CDT Monday Jul 28 2014

VFR conditions expected through the period. Mostly clear skies
will prevail tonight in Minnesota and along the St Croix river...but
clouds around 5000 feet above ground level continue dropping southward from the
Western Lake Superior area. Showers and even some thunderstorms
were associated with this...but it should stay east of Keau. It
might nick Ladysmith tonight.

Some showers are possible in western wisc Tuesday afternoon along
with some thunder. Threat is not yet strong enough to include
thunderstorms and rain in the Keau taf but did add vcsh. Northwest wind might gust above 10
knots amid daytime heating.

Kmsp... VFR through the period. Mostly clear tonight with light
winds...then more cumulus will develop late Tuesday morning. Some of
this may go broken Tuesday afternoon. Any showers should remain
east of kmsp. Midday or afternoon is also when there may be a few
gusts 10-15 kts but have not indicated this in the tafs right now.

/Outlook for kmsp/

Wednesday...VFR. Winds northwest 5-10 kts.
Thursday...VFR. Winds northwest 5 kts.
Friday...VFR. Winds northwest 5 kts.


Mpx watches/warnings/advisories...


long term...jrb

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