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FXUS63 KMKX 291025

Area Forecast Discussion
National Weather Service Milwaukee/Sullivan WI
525 AM CDT Thu Jun 29 2017

Some patchy MVFR CIGS will be moving across the area before 8
am...thereafter, look for VFR conditions through much of the
evening. Another wave of showers and thunderstorms should move
into southern Wisconsin toward 7 pm this evening. The bulk of the
rain will be limited to far southern Wisconsin, but some showers 
and storms will spread north of Milwaukee and Madison after 
midnight. MVFR CIGS return after 06z Friday with some IFR CIGS 
possible around 12z Friday, then conditions improve toward late 
morning on Friday. Southwest winds will diminish this afternoon. 


.PREV DISCUSSION... (Issued 328 AM CDT Thu Jun 29 2017) 


Today and tonight...Forecast confidence is medium. 

We're in between mid level waves for much of today, so things will
be mostly quiet through the morning and afternoon. We may even see
some sunshine with highs pushing into the lower 80s. Dewpoints
will remain elevated, so look for it to feel humid/muggy. Showers
and storms approach southwest WI again toward evening. 

Another mid level wave arrives by evening with rather decent deep
level forcing. We lack the good thermal/CAPE and deep layer shear
support, so the threat for severe storms is rather low. But, it
can't be ruled out either.  So the roughly southern two tier of 
counties are in a marginal risk for severe storms from late 
afternoon through tonight. The best chance for rain will be along 
the WI/IL border. 


Friday through Sunday...Forecast confidence is medium:

Multiple waves are forecast to move through broad cyclonic flow
Friday and Saturday, bringing more shower/storm chances. Not easy
to time the individual impulses yet, so just went with chance

Models are suggesting a stronger wave and a surface front to drop
through on Sunday, possibly bringing a better chance of widespread

Left temps near a consensus blend of models Friday through the 
weekend, due to uncertainty in timing of cloud cover and precip. 
Looks like highs should be within a couple degrees of normal. 

Monday through Wednesday...Forecast confidence is low to medium:

High pressure will build into the region from the north for the
first half of next week, with a frontal boundary just to the south
of the high. Shower/storm chances will continue near the front.
Models differ with the southward extent of the high during this
period. The ECMWF has the high far enough south for dry weather
Mon-Wed, while the GFS keeps the high and front farther north,
bringing shower/storm chances each day. Kept some precip chances
in the forecast for now due to the uncertainty. 

Temps should remain about the same into early next week. 


Any lingering MVFR CIGS early this morning will lift to VFR levels
by or shortly after sunrise. VFR conditions are then expected into
the early evening. Another round of showers and thunderstorms will
overspread the area this evening. Widespread MVFR CIGS are
expected after 06z Friday, lingering through the morning on


I'll extend the small craft advisory through mid morning due to 
lingering higher waves. Winds are diminishing, but remain elevated
enough to keep the waves up. Otherwise, winds and waves look to
remain below small craft advisory levels into early next week. 


LM...Small Craft Advisory until 10 AM CDT this morning for LMZ643>646.



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