FXUS63 KGRB 051118

AFDGRB



Area Forecast Discussion

National Weather Service Green Bay WI

618 AM CDT Tue May 5 2026



Updated aviation portion for 12Z TAF issuance



.KEY MESSAGES...



- Cooler temperatures are expected for the rest of the week, with

  overnight lows approaching freezing. There is a 30-80% chance

  for frost from central to east-central WI Tuesday and Wednesday

  nights (highest in central WI, lowest near the lakeshore). 



- Minor precip chances this week with little to no impacts.



&&



.DISCUSSION...

Issued at 236 AM CDT Tue May 5 2026



Surface cold front is southeast of the state now which will allow

winds to subside overnight, and marks the start of a cooler 

pattern. The main impacts over the next few days will be 

frost/freeze potential during the nights. There are minor precip 

chances, but amounts and impacts will be minimal. 



Temperatures:

Highs today will be about 15 to 20 cooler than Monday, in the 

upper 40s to middle 50s. Similar readings persist on Wednesday and

Thursday, and then return closer to seasonal normals on Friday 

and this weekend, in the upper 50s and 60s. 



Overnight lows will be the numbers to watch, as temperatures 

approach freezing Tuesday night through Thursday night. This will

likely warrant frost or freeze headlines for central and east- 

central WI (these products have not yet begun for northern WI). NBM

probabilities show a 30-100% chance of reaching 36 degrees or 

cooler Tuesday and Wednesday nights, with the lowest probabilities

in east-central WI near the lakeshore. Frost potential is less 

certain Thursday night, with probabilities of 5-60% in central 

and east-central WI. By the weekend, overnight lows look to stay

warm enough to avoid frost where the growing season has started. 



Precip: 

A few precipitation opportunities throughout the week, but impacts

from any precipitation will be minimal. Upper low will spin

northward across Ontario and Hudson Bay the next couple days,

which will keep northeast Wisconsin in northwest flow and send a

few shortwaves through the area. Today's shortwave is likely to be

dry, with only the HRRR showing a few spits of precip. NBM

probabilities for 0.01" of rain are around 5%. Similar situation

on Wednesday, with a 10-20% probability of measurable precip 

across northern WI. The potential is best on Thursday (20-40%) for

some measurable rain, again not amounting to much more than a few

hundredths.



&&



.AVIATION...for 12Z TAF Issuance

Issued at 617 AM CDT Tue May 5 2026



VFR conditions are expected through the TAF period. Band of mid-

level clouds will continue to shift southeast across east-central 

WI early this morning, with other mid and high clouds expected 

today into tonight. Lower clouds, mainly between 3000-8000 ft, 

will move across locations near the MI border and Door County 

early in the day, with additional daytime cu developing through 

the day, with the greatest coverage north and west of the Fox 

Valley. Some of these clouds will linger into tonight.



Winds died off during the overnight hours, but west winds will 

pick back up through mid-morning, with gusts to around 20 kts 

late this morning and afternoon, before subsiding this evening.



&&



.GRB WATCHES/WARNINGS/ADVISORIES...

None.



&&



$$



DISCUSSION.....KLJ

AVIATION.......Bersch