NWS-Milwaukee/Sullivan Forecast Discussion

						FXUS63 KMKX 111007 AAA
AFDMKX

Area Forecast Discussion...UPDATED
National Weather Service Milwaukee/Sullivan WI
507 AM CDT Sat Jul 11 2026

.KEY MESSAGES...

- Hot temperatures will return early next week, with highs of at
  least 90 degrees possible Monday through Wednesday.

- Dry weather expected through Wednesday, with thunderstorm
  chances returning late in the week.

&&

.UPDATE...
Issued 507 AM CDT Sat Jul 11 2026

Patchy river valley fog is possible through the early morning
hours. Otherwise, expect decreasing high level clouds this
morning, with mostly sunny skies likely the remainder of the
day. Overall, the forecast looks on track through the
afternoon, with no significant updates anticipated.

DDV

&&

.SHORT TERM...
Issued 1256 AM CDT Sat Jul 11 2026

Today through Sunday night:

Clouds will slowly exit southeastward through this morning as
high pressure settles into the Great Lakes. As clouds exit, some
areas will manage to cool to saturation in low-lying areas,
especially in the Wisconsin River Valley where clouds exit
earliest. After sunrise, expect fog to lift quickly and clear
skies to dominate through the afternoon under high pressure. Light
easterly winds are expected, with highs in the mid to upper 80s
along and west of the Kettle Moraine, and highs in the upper 70s
to low 80s east of the Kettle Moraine where onshore flow will keep
temperatures cooler. Winds diminish to become light and variable
to calm once again overnight, but a drier airmass will likely
prevent fog formation. Expect lows in the low to mid-60s.

Sunday, high pressure builds overhead, keeping winds very light. A
lake breeze will develop in the afternoon, reducing highs in the
immediate vicinity of the lakeshore to the low 80s. Inland, expect
highs in the upper 80s with heat index values near observed air
temperatures due to continued dry airmass. Overnight lows Sunday
are expected to be in the low to mid-60s once again.

MH

&&

.LONG TERM...
Issued 1256 AM CDT Sat Jul 11 2026

Sunday night through Friday:

As high pressure slides into the Ohio Valley, southerly return
flow develops across southern Wisconsin, bringing back in high
temperatures in the upper 80s to low 90s for the first part of the
week. With west-southwesterly winds remaining light on Monday, a
lake breeze may develop and cool lakeshore counties somewhat.
However, for Tuesday and Wednesday expect southwesterly winds to
become steady and bring temperatures near 90 degrees all the way
to the lakeshore. Even with these high temperatures potentially
locally pushing 95 degrees given 925 mb mixing temperatures of 26
to 28 degrees C, not anticipating heat index values to exceed 100
degrees due to a relatively dry airmass in place (dewpoints in
the 60s).

Low pressure deepens in the lee of the Rockies Wednesday night
into Thursday, bringing a zone of frontogenesis to the Upper
Midwest along the northern edges of the 250 mb ridging. With this
ridge riding setup in place, potential for shortwaves riding
through the frontogenesis/upper level ridging develops by Friday
and into Saturday. Periods of thunderstorms therefore become
possible (20-30% chances Thursday night through Saturday night due
to model discrepancies in timing of individual shortwaves).

MH

&&

.AVIATION...
Issued 507 AM CDT Sat Jul 11 2026

Patchy river valley fog is possible through the early morning
hours and will be possible again tonight. Otherwise, expect
decreasing high level clouds this morning, with FEW to SCT
diurnal cumulus around 5 kft late morning and afternoon away
from Lake Michigan. East to northeast winds of 5 to 10 knots
today will become light and variable under high pressure for
tonight and Sunday, except for east to southeast winds 5-10
knots near Lake Michigan tomorrow.

DDV

&&

.MARINE...
Issued 1256 AM CDT Sat Jul 11 2026

High pressure around 30.0 inches currently over southern Ontario
and northern portions of the Great Lakes will slowly sink
southward through the weekend into Monday as it strengthens to
30.2 inches, settling over the Ohio Valley Monday into Tuesday.
Light and variable winds are expected through Monday night,
increasing and becoming southwesterly into Tuesday. A brief
period of gusts to 30 kt is possible across the northern third on
Tuesday as low pressure moves through the Hudson Bay. Gales are
not likely at this time. A weak cold front from the Hudson Bay low
will shift winds to northwesterly into Wednesday. Winds become
variable again into late week, with thunderstorm chances
increasing into late week.

MH

&&

.MKX WATCHES/WARNINGS/ADVISORIES...
WI...None.
LM...None.
&&

$$

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