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Area forecast discussion 
National Weather Service Twin Cities/Chanhassen Minnesota
641 am CDT Sat Jul 30 2016

Updated for 12z aviation discussion...
issued at 637 am CDT Sat Jul 30 2016


Short term...(today and tonight)
issued at 451 am CDT Sat Jul 30 2016

Today will be another mostly sunny day with light winds and highs
near 80. A few showers and thunderstorms are possible along the
Mississippi River valley during the afternoon, but coverage will be
very scarce.

Split flow remained in place across the region meaning very light
winds from the surface up through 300mb. Later today the upper level
jet will increase slightly to around 25-30kts as the back side of an
upper level trough moves across the region. This should promote
subsidence and hold off any chance for showers and thunderstorms,
but forecast soundings off the GFS and NAM show a thin layer of
instability along the Minnesota/WI border during the afternoon. Hires
models show spotty showers and thunderstorms, so added a 15 percent
chance of precipitation for this afternoon. Have pretty high
confidence that a few showers and thunderstorms will be around, but
most locations will remain dry. The threat for severe weather is
very low. Tonight will be dry as well for most location, but a
bit warmer as southerly winds keep overnight lows near 60 for most
locations. A few thunderstorms are possible in far western Minnesota.

Long term...(sunday through friday)
issued at 451 am CDT Sat Jul 30 2016

Not much change to the extended part of the forecast. Heat and
humidity remain on track for the middle of the week with highs near
90 and dewpoints in the lower 70s. This will lead to heat indices
around 95 to 100f Wednesday afternoon, while maxwetbulbglobe
temperatures reach the mid 80s. In other words, it will be hot and
uncomfortable, but should not be dangerous if proper precautions are
taken. There are a few chance for thunderstorms, but by far the
highest risk day in terms of both coverage and severity is
Wednesday evening/night.

Of course the temperatures are dependent on cloud cover and
precipitation. There are slight chances for showers and
thunderstorms most of next week, but the best chances appear to be
Monday night and Wednesday night. Right now there is not an outlook
by Storm Prediction Center for severe weather, but forecast soundings show veered wind
profile with around 1500 to 2000 j/kg Monday night. Wednesday has
higher cape with values near 5000 j/kg, but the wind profile is less
favorable, but still supportive, for organized convection. At this
point the highest threat for severe storms is across northern Minnesota and
northern WI where the deep layer shear is stronger, but will
continue to monitor the trend and would not be surprised to have
the area outlooked within the next couple of days. Looking ahead,
cooler less-humid weather will move in for next weekend.


Aviation...(for the 12z tafs through 12z Sunday morning)
issued at 637 am CDT Sat Jul 30 2016

VFR conditions expected with light southeast winds. A few sites
prone to fog may see another round early Sunday morning.

VFR conditions throughout with light southeast winds. A few
showers or thunderstorms are possible this afternoon, but
confidence is too low to include mention in the tafs.

/Outlook for kmsp/
Mon...VFR. Southeast wind 10 kt.
Tue...mainly VFR with chance MVFR/tsra. Wind light/variable.
Wed...VFR with thunderstorms and rain possible late. Wind south-southeast at 10g15kt.


Mpx watches/warnings/advisories...


Short term...jrb
long term...jrb

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