Sun Prairie, Wisconsin 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

505
FXUS63 KMKX 180320
AFDMKX

Area Forecast Discussion
National Weather Service Milwaukee/Sullivan WI
920 PM CST Fri Jan 17 2025

.KEY MESSAGES...

- An Arctic cold front will cross southern Wisconsin this
  evening, allowing a frigid air mass to begin working into the
  region.

- The arctic air remains entrenched over southern Wisconsin
  from this weekend into early next week. Cold weather headlines
  will likely be needed, particularly during the Sunday through
  Tuesday night time frame.

- Temperatures climb back toward normal later next week.

&&

.UPDATE...
Issued 920 PM CST Fri Jan 17 2025

A dry front continues to push through this evening and while
there is certainly moisture aloft supporting some
flurry/sprinkle mix the dry air in the low levels is clearly too
difficult to overcome and radar shows this very clearly over the
last hour or so as the front has pushed closer to the radar.
Once the front passes expect winds to turn northwest and
gradually ramp up. Also enjoy these temperatures now because its
the warmest it will be for the next week at least.

Kuroski

&&

.SHORT TERM...
Issued 307 PM CST Fri Jan 17 2025

Tonight through Saturday night:

A cold front is expected to sweep through the forecast area
this evening. Models soundings show increased saturation along
and just behind the cold front, but there is still a signal of
a lot of dry air below 10 kft. Kept a mention of flurries going
in case some snow survives the dry later. Temperatures will drop
behind the front tonight under breezy northwest winds, with
temps not warming much Saturday as cold advection aloft
persists. With highs only in the teens tomorrow, wind chills
are not expected to rise much above 5 degrees.

DDV

&&

.LONG TERM...
Issued 307 PM CST Fri Jan 17 2025

Saturday night through Friday:

Temperatures aloft will continue to crash Saturday night into
early next week as a reinforcing shot of cold air moves through.
Subzero wind chills are expected from Saturday evening through
Wednesday morning. The coldest period will be Sunday through
Tuesday, when wind chills may struggle to get above -15 to -20
during the day, and will drop to -20 to -30 at night. Cold
weather headlines will likely be needed for this coldest period.

Temperatures will begin to recover on Wednesday, approaching
normal values by the end of the week. Dry weather is expected
through the middle of next week, with models hinting at a chance
for light snow by Thursday as a shortwave moves through. Kept
the forecast dry for now given a continued low level of
confidence this far out in the forecast.

DDV

&&

.AVIATION...
Issued 920 PM CST Fri Jan 17 2025

A dry front continues to push through this evening and while
there is certainly moisture aloft supporting some
flurry/sprinkle mix the dry air in the low levels is clearly too
difficult to overcome and radar shows this very clearly over the
last hour or so as the front has pushed closer to the radar.
Once the front passes expect winds to turn northwest and
gradually ramp up. CIGS are expected to remain VFR through the
TAF period though there is a brief period tonight that could
yield some MVFR CIGS in the western parts of the state.

Kuroski

&&

.MARINE...
Issued 307 PM CST Fri Jan 17 2025

Gale force winds will continue into early evening across the
open waters, as high pressure centered over North Carolina
departs east and low pressure moves east through southwest
Ontario. The low to the north will drag a cold front through
this evening, with winds becoming northwest behind the front
while dropping below gale force by mid-evening. The Small Craft
Advisory remains in effect through Saturday afternoon.

Breezy northwest to west winds will then continue through the
first part of next week and will combine with a much colder
airmass for a period of freezing spray. Heavy freezing spray is
mostly likely across the eastern two-thirds of the lake Sunday
into early Wednesday.

DDV

&&

.MKX WATCHES/WARNINGS/ADVISORIES...
WI...None.
LM...Small Craft Advisory...LMZ643-LMZ644-LMZ645-LMZ646 until 5 PM
     Saturday.

&&

$$

Visit us at weather.gov/milwaukee

Follow us on Facebook, Twitter, and YouTube at:
www.facebook.com/NWSMilwaukee
www.twitter.com/NWSMilwaukee
www.youtube.com/NWSMilwaukee