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National Weather Service Milwaukee/Sullivan WI
329 AM CDT MON JUL 25 2016

.TODAY AND TONIGHT...Forecast Confidence Is High.

An upper level shortwave will move across the eastern Great Lakes
today, with a relatively weak zonal flow across the north central
U.S. Little in the way of upper divergence or 700 mb upward

A weak 700 mb northwest flow is expected, with a weak 700 mb
trough axis moving across southern Wisconsin.

700 mb RH is low, but does increase northwest of Madison around
sunrise Tuesday. 850 mb moisture increases a little, with surface
heating, which should result in developing cumulus. However, GFS
forecast soundings show mainly scattered fair weather cumulus.
This is due to a weak but rather deep stable layer above 850 mb,
with dry air and a fairly well mixed boundary layer below.

Will use the high resolution HRRR experimental winds, that has
any lake breeze confined to areas right along the lake north of
Milwaukee. It may reach 5 miles or so inland across Racine and
Kenosha county.

With the surface high across southern Wisconsin tonight, will go
with areas of fog due to the recent rains, calm winds and clear

.TUESDAY THROUGH WEDNESDAY NIGHT...Forecast Confidence Is Medium.

Models remain in good agreement with high pressure sliding
southeast through the region Tuesday, then shifting further
southeast Tuesday night. This should bring a dry and warm Tuesday
across the area. Highs in the middle 80s look reasonable. Lake
breeze is expected by afternoon, keeping those areas cooler.

Models then show the main feature for Tuesday night into Wednesday
night to be a slow moving 500 mb shortwave trough. This feature
shifts slowly eastward across Iowa into southern Wisconsin and
northern Illinois, especially Wednesday into Wednesday night.
There is also a weaker 500 mb vorticity maximum that shifts across
the area Tuesday night. 

Differential cyclonic vorticity advection associated with these
features should bring a gradual increase in POPs Tuesday night
into Wednesday night across the area. Best POPs would be in the
west Wednesday night. Area forecast soundings are showing some
potential for heavy rainfall Wednesday night, with favorable warm
cloud processes and relatively low storm motions.

Warm and humid conditions should continue during this period, with
another lake breeze Wednesday afternoon near the lake. 

.THURSDAY THROUGH SUNDAY...Forecast Confidence Is Medium.

ECMWF and GFS show the 500 mb shortwave trough slowly moving
through the region Thursday into Thursday night, with the GFS
actually having two separate ones moving through. Either way, this
should maintain decent POPs during this period. Again, may need to
watch for heavy rainfall chances into Thursday, as warm cloud
processes remain favorable. Warm and humid conditions should

The ECMWF has a more amplified 500 mb shortwave trough moving
through the region than the GFS Friday into Saturday. Continued
with some POPs during most of this period with the uncertainty in
the models. 



Some patchy fog in low-lying rural areas and river valleys in 
northwest areas should last through around sunrise. Still
thinning cirrus over the southeast. Looking for VFR conditions
today, with mainly late morning and afternoon scattered fair
weather cumulus.

With the surface high across southern Wisconsin tonight, will go
with areas of fog, due to the recent rains, calm winds and clear
skies. Some IFR/LIFR likely in low areas, with MVFR possible at



High pressure over the Upper Mississippi Valley will move into
southern Wisconsin tonight. Light northwest winds will likely
become east, as a lake breeze tries to develop this afternoon.

Winds and waves will remain below criteria through Tuesday with
quiet weather.


.MKX Watches/Warnings/Advisories...


Tuesday THROUGH Sunday...Wood

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