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FXUS63 KMKX 272136

Area Forecast Discussion
National Weather Service Milwaukee/Sullivan WI
336 PM CST Mon Feb 27 2017


TONIGHT AND TUESDAY... Forecast confidence is medium.

A warm front will bring an area of showers with a chance of elevated 
thunderstorms to southern WI tonight on the nose of a low level jet. 
It looks like there will be a back edge to these showers so there 
should be a lull during the mid to late morning. Expect patchy fog 
and low clouds to linger. Despite the clouds, temperatures should 
rise into the 50s with a good push of warm air on southerly winds.

A coupled upper jet and another nose of the low level jet just ahead 
of the surface low will bring another round of showers and scattered 
thunderstorms midday. These will be elevated, but could produce some 
small hail.

SPC pushed the Day 2 marginal risk all the way up to Sheboygan now. 
This is to cover the hail threat. The surface low and associated 
cold front is forecast to track right through far northeast IL, but 
it could clip southeast WI during the late afternoon and early 
evening hours. This would allow for potential surface-based 
convection. There is high shear but low instability, so a small 
chance for severe storms.

.TUESDAY night AND WEDNESDAY...Forecast Confidence...Medium

Low pressure will exit far southeast Wisconsin Thursday early 
evening. There would still be a marginal risk of severe 
thunderstorms far southeast early in the evening before the cold 
front exits. 

The low is forecast to intensify over Lower Michigan with strong
cold air advection across southern Wisconsin. Precipitation will 
be in the form of rain before midnight, slowly transitioning to 
a mix of snow northwest Tuesday night, then to mainly snow across
the area by Wednesday afternoon. GFS has come in line with the 
NAM/ECMWF showing the potential for 1 to 2 inches of snow on 
Wednesday. A few 3 inch totals not out of the question if the 
NAM/ECMWF verify.


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

Could see a little snow Thursday as a low moves across southern
Wisconsin. The GFS/NAM would indicate a 1 to 2 inch snow
potential, but the ECMWF is much less.  

Decent agreement among models for Friday, showing high pressure 
and near normal temperatures. South winds on the back side of the
high begins a moderation in temperatures Friday evening and 

GFS and ECMWF show a little snow Fri night due to lift with the warm

Another trough may bring light rain/sprinkles Saturday evening
before south winds and warming begin again sunday.

.MOnday...Forecast Confidence...Medium

As low pressure approaches rain may develop Sunday night into
Monday. The ECMWF and DGEX are quicker and deepen a low over Lower
Michigan. The GFS is slower, and has a more northern track. 



A warm front will bring a surge of rain into southern WI after 
midnight tonight. There is a small chance of thunderstorms with this 
round. Another round of showers and a few storms is possible midday. 
The better chance of showers and scattered storms is expected along 
a cold front late Tue afternoon into the evening.

Ceilings should lower to MVFR after the rain arrives tonight with 
some IFR conditions expected toward 12z Tuesday. Ceilings may rise 
above IFR for a time on Tuesday, then go back down Tuesday night.



Southeast winds will approach small craft advisory levels very late 
tonight into early Tuesday morning as low pressure approaches from 
the west.  Once the low passes by, northerly winds will again 
approach small craft advisory levels on Wednesday. Small craft 
should exercise caution during these periods.



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