313  
FXUS63 KGRB 201114  
AFDGRB  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE GREEN BAY WI  
614 AM CDT FRI MAR 20 2026  
 
UPDATED AVIATION PORTION FOR 12Z TAF ISSUANCE  
   
KEY MESSAGES  
 
- AREAS OF DENSE FOG POSSIBLE THIS MORNING ACROSS CENTRAL TO  
NORTH- CENTRAL WISCONSIN.  
 
- NEXT CHANCE OF A WINTRY MIX AND SNOW (20-40%) SATURDAY NIGHT  
INTO SUNDAY, ESPECIALLY OVER NORTHERN WISCONSIN.  
 
- TEMPERATURES SURGING ABOVE NORMAL TODAY AND SATURDAY, WITH THE  
WARMTH PEAKING SATURDAY (MID TO UPPER 50S).  
 
- SNOWMELT AND INCREASED FLOWS AND RISING LEVELS ON RIVERS AND  
STREAMS ARE EXPECTED. SEVERAL RIVERS MAY REACH BANKFULL OR EVEN  
MINOR FLOOD STAGE BEGINNING THIS WEEKEND.  
 
 
   
DISCUSSION  
 
ISSUED AT 122 AM CDT FRI MAR 20 2026  
 
A CLIPPER SYSTEM WILL BRING SOME LIGHT RAIN TO FAR NORTHEAST  
WISCONSIN EARLY THIS MORNING, WITH SNOW AND FREEZING RAIN POSSIBLE  
NEAR THE MICHIGAN BORDER. IN ADDITION, SOME PATCHY FOG WILL BE  
POSSIBLE LATER THIS MORNING WITH ABUNDANT LOW LEVEL MOISTURE OVER  
A COLD SNOWPACK. THE WORST VISIBILITY RESTRICTIONS ARE EXPECTED  
ACROSS CENTRAL AND NORTH-CENTRAL WISCONSIN, WHERE LOCALLY DENSE  
FOG IS POSSIBLE.  
 
DRY WEATHER IS THEN EXPECTED THE REST OF TODAY AS TEMPERATURES  
CONTINUE THEIR CLIMB ACROSS THE WESTERN GREAT LAKES REGION. HIGHS  
TODAY ARE EXPECTED TO RANGE FROM THE LOWER TO MIDDLE 40S ACROSS  
THE FOX VALLEY WITH AROUND 50 DEGREES NORTH AND WEST OF THE FOX  
VALLEY WHERE NBM PROBABILITIES OF EXCEEDING 50 DEGREES ARE  
50-80%.  
 
SATURDAY WILL LIKELY BE THE WARMEST DAY OF THE WEEK AS AN  
APPROACHING LOW PRESSURE SYSTEM FROM THE PLAINS BRINGS A SURGE OF  
WARM AIR OVER THE WESTERN GREAT LAKES REGION. NBM PROBABILITIES OF  
EXCEEDING 60 DEGREES HAVE INCREASED TO 40-80% SOUTHWEST OF A LINE  
FROM MOSINEE TO OSHKOSH. THE REST OF THE AREA WILL LIKELY SEE  
TEMPERATURES IN THE 40S ACROSS FAR NORTHEAST WISCONSIN, WITH 50S  
IN BETWEEN THESE AREAS. PRECIPITATION ON SATURDAY WILL MAINLY BE  
LIMITED TO FAR NORTHERN WISCONSIN NEAR THE MICHIGAN BORDER  
ASSOCIATED WITH ISENTROPIC LIFT NEAR THE WARM FRONT.  
 
THE COLD SIDE OF THIS LOW PRESSURE SYSTEM WILL TRACK THROUGH THE  
AREA SATURDAY NIGHT, BRINGING COLDER TEMPERATURES AND A RAIN/SNOW  
MIX AS A COLD FRONT SINKS SOUTH THROUGH SUNDAY. THE CHANCE OF  
PRECIPITATION IS 20-40%, WITH MOST OF THE PRECIPITATION OCCURRING  
ON SATURDAY NIGHT. NBM 24 HOUR PROBABILITIES FOR ACCUMULATING  
SNOW HAVE TRENDED DOWN PRECIPITOUSLY AND ARE CURRENTLY DE MINIMIS,  
CLOCKING IN AT 10% OR LESS ACROSS FAR NORTH-CENTRAL AND NORTHEAST  
WISCONSIN ENDING SUNDAY EVENING.  
 
HIGH PRESSURE WILL THEN PROVIDE DRY WEATHER TO THE AREA EARLY  
NEXT WEEK. TEMPERATURES WILL START OFF AT OR SLIGHTLY BELOW  
NORMAL, BUT QUICKLY REBOUND TO SLIGHTLY ABOVE NORMAL BY THE MIDDLE  
OF NEXT WEEK. A CLIPPER SYSTEM WILL ALSO BE MOVING THROUGH THE  
MIDDLE OF NEXT WEEK. THIS SYSTEM HAS A LOT OF UNCERTAINTY  
SURROUNDING IT, AS EVIDENCED BY THE LARGE SPREAD IN PROBABILISTIC  
DATA. CURRENT 24 HOUR NBM PROBABILITIES FOR AN INCH OR MORE OF  
SNOW DURING THE MIDDLE PART OF NEXT WEEK ARE 20-30% ACROSS NORTH-  
CENTRAL WISCONSIN.  
 
 
   
AVIATION  
FOR 12Z TAF ISSUANCE  
ISSUED AT 613 AM CDT FRI MAR 20 2026  
 
MAIN CONCERN THIS MORNING IS MVFR AND POSSIBLE IFR FOG ACROSS  
CENTRAL AND NORTH-CENTRAL WISCONSIN TAF SITES. ANY FOG SHOULD  
CLEAR UP BY 14/15Z WITH VFR CONDITIONS EXPECTED THE REST OF TODAY.  
WINDS WILL GENERALLY BE WEST TO NORTHWEST BELOW 10 KNOTS, WITH A  
LAKE BREEZE BOUNDARY TURNING WINDS SOUTHEAST ACROSS EAST-CENTRAL  
WISCONSIN AND AFFECTING KGRB/KATW/KMTW THIS AFTERNOON. AREAS OF  
FOG ARE EXPECTED AGAIN TONIGHT INTO SATURDAY MORNING, DROPPING  
CONDITIONS TO MVFR/IFR.  
 
 
   
HYDROLOGY  
 
ISSUED AT 122 AM CDT FRI MAR 20 2026  
 
AS TEMPERATURES WARM ACROSS THE REGION, THE SNOWMELT WILL RESULT  
IN INCREASING FAST FLOWS AND RISING RIVER LEVELS. SOME RIVERS  
COULD REACH BANKFULL OR EVEN MINOR FLOOD STAGE. THE LACK OF A  
RAPID, SIGNIFICANT WARMUP POINTS TO A MORE GRADUAL RISE IN AREA  
RIVERS AS OPPOSED TO WIDESPREAD RAPID RISE FLOODING. THAT BEING  
SAID, THE FLOODING SITUATION WILL BE MONITORED CLOSELY GIVEN HOW  
MUCH WATER IS LOCKED UP IN THE CURRENT SNOWPACK ACROSS THE REGION.  
LATEST SNOW WATER EQUIVALENT (SWE) HERE AT OUR OFFICE IS NOW 2.88  
INCHES WITH A SNOW DEPTH OF 14 INCHES. THIS MATCHES THE CURRENT  
NOHRSC SNOW DEPTH AND SWE ANALYSIS PRETTY WELL. MODELED SNOWPACK  
TEMPERATURE FROM THE NOHRSC SITE POINTS TO RIPENING OF SNOWPACK  
(REALLY STARTING THE MELTING/RUNOFF PROCESS) OVER CENTRAL WI AS  
EARLY AS TODAY, WITH MORE WIDESPREAD RIPENING OF SNOWPACK UP OVER  
THE AREA ON SATURDAY.  
 
 
   
GRB WATCHES/WARNINGS/ADVISORIES  
 
NONE.  
 
 
 
 
 
DISCUSSION.....KURIMSKI  
AVIATION.......KURIMSKI  
HYDROLOGY......KURIMSKI  
CLICK HERE TO GO TO PREVIOUS BULLETINS.
The Nexlab WI Page
Main Text Page