513
FXUS63 KGRB 122254
AFDGRB
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GREEN BAY WI
554 PM CDT THU MAR 12 2026
FORECAST DISCUSSION FOR ROUTINE AFTERNOON FORECAST ISSUANCE
KEY MESSAGES
- WINTER SYSTEM TO BRING 5 TO 9 INCHES OF SNOWFALL TO NORTHERN
WISCONSIN, WITH AMOUNTS RAPIDLY TAPERING OFF SOUTHWARDS WHERE
RAIN MAY MIX IN. WINTER STORM WARNINGS AND WINTER WEATHER
ADVISORIES ARE IN EFFECT.
- STRONG WINDS ACCOMPANY THE SYSTEM TONIGHT THROUGH FRIDAY, WITH
GUSTS UP TO 40 TO 50 MPH POSSIBLE (30-60%), WHICH WILL INCREASE
IMPACTS OF ANY FALLING SNOW AND MAY RESULT IN RAPID REDUCTIONS
IN VISIBILITY AT TIMES DUE TO PATCHY BLOWING AND DRIFTING SNOW.
WIND ADVISORIES ARE IN EFFECT.
- MAJOR WINTER STORM IS EXPECTED FROM SATURDAY NIGHT THROUGH
MONDAY WITH THE POTENTIAL FOR SIGNIFICANT DISRUPTIONS AND
IMPOSSIBLE TRAVEL CONDITIONS ACROSS THE REGION. SIGNIFICANT SNOW
TOTALS ARE EXPECTED, WITH HIGH PROBABILITIES FOR EXCEEDING 12
INCHES OF SNOWFALL (70-100%). STRONG WIND GUSTS ARE ALSO
EXPECTED. THOSE WITH TRAVEL PLANS, INCLUDING AIR TRAVEL, SHOULD
MONITOR THE WEATHER CLOSELY AND MAKE ALTERNATIVE PLANS. A
WINTER STORM WATCH HAS BEEN ISSUED FOR THE ENTIRE AREA.
DISCUSSION
ISSUED AT 554 PM CDT THU MAR 12 2026
TONIGHT THROUGH FRIDAY...A FAST-MOVING CLIPPER SYSTEM IS EXPECTED TO
IMPACT THE REGION DURING THIS FORECAST PERIOD AND BRING SEVERAL
INCHES OF SNOWFALL ACROSS NORTHERN WI, WITH LESSER AMOUNTS ACROSS
THE SOUTHERN PORTION OF THE FORECAST AREA. IMPRESSIVE DYNAMICS WITH
THIS SYSTEM, INCLUDING UPPER-LEVEL LFQ PLACEMENT, MIDDLE LEVEL
SHORTWAVE ENERGY, AND STRONG F-GEN ACROSS THE FAR NORTH, THE SNOW
WILL ACCUMULATE QUICKLY WITH PERIODS OF 1"/HOUR SNOWFALL RATES
DURING THE OVERNIGHT PERIOD (ABOUT 10PM - 3AM). THE HIGHEST SNOWFALL
AMOUNTS OF 5 TO 9 INCHES IS FORECAST ALONG AND NORTH OF HIGHWAY 29,
INCLUDING FAR NORTHERN DOOR COUNTY. SNOWFALL AMOUNTS WILL DROP OFF
SIGNIFICANTLY SOUTH OF HIGHWAY 29, DUE TO WARMER AIR LIFTING INTO
THE REGION, ALLOWING RAIN TO MIX IN WITH THE SNOW AT TIMES. BY
FRIDAY MORNING, THE CLIPPER (LOW PRESSURE) WILL BE MOVING OVERHEAD,
LEADING TO POTENTIAL DRY SLOTTING, ESPECIALLY ACROSS CENTRAL AND
EAST-CENTRAL WI. THIS WOULD RESULT IN ONGOING SNOW ACROSS THE NORTH,
AND SNOW ENDING ACROSS THE SOUTHERN AREAS; HOWEVER, CAMS INDICATE
POTENTIAL VIGOROUS SNOW SHOWERS DEVELOPING IN THIS DRY SLOT DUE TO
THE PROXIMITY OF SOME STRONGER LOW-LEVEL DYNAMICS/INSTABILITY. ANY
SNOW SHOWER MOVING THROUGH THE AREA DURING THIS TIME (EARLY FRIDAY
MORNING), COULD CREATE BRIEF/QUICK REDUCTIONS IN VISIBILITY. LIGHT
SNOW SHOWERS OR FLURRIES WILL THEN CONTINUE ACROSS THE AREA FOR THE
REMAINDER OF THE DAY ON FRIDAY, WITH THE SNOW ENDING FRIDAY EVENING.
NO CHANGES WERE MADE TO THE WINTER STORM WARNINGS ACROSS THE NORTH
AND WINTER WEATHER ADVISORIES IN PORTIONS OF CENTRAL AND EAST-
CENTRAL WI, INCLUDING DOOR COUNTY.
DUE TO HOW WOUND UP THIS CLIPPER SYSTEM IS, THE TIGHT PRESSURE
GRADIENT WILL RESULT IN STRONG WIND GUSTS AT THE SURFACE. STRONG
SOUTHEAST WINDS ARE EXPECTED THIS EVENING, TURNING WEST/NORTHWEST BY
FRIDAY MORNING WITH THE MOVEMENT OF THE CLIPPER SYSTEM. WIND GUSTS
UP TO 40 TO 50 MPH ARE POSSIBLE. WINDS SUBSIDE FRIDAY EVENING. THE
COMBINATION OF THE SNOW AND WIND WILL RESULT IN PATCHY BLOWING AND
DRIFTING SNOW, ESPECIALLY ACROSS THE NORTH WHERE SNOW IS EXPECTED. A
FEW POWER OUTAGES ARE ALSO POSSIBLE ACROSS THE ENTIRE AREA AND
TRAVEL WILL BE DIFFICULT FOR HIGH PROFILE VEHICLES THROUGHOUT THIS
FORECAST PERIOD. NO CHANGES WERE MADE TO THE WIND ADVISORY ACROSS
PORTIONS OF CENTRAL AND EAST-CENTRAL WI.
WEEKEND SYSTEM...A MAJOR WINTER SYSTEM, VIA A COLORADO LOW, IS
EXPECTED TO BRING SIGNIFICANT IMPACTS/DISRUPTIONS TO THE FORECAST
AREA WITH SIGNIFICANT SNOWFALL TOTALS AND STRONG WINDS. WHILE THERE
HAS BEEN A SUBTLE NORTHERLY SHIFT WITH THE MAIN TRACK OF THE SYSTEM,
THE FORECAST AREA WILL STILL BE UNDER THE SPOTLIGHT FOR POTENTIALLY
SEEING THE GREATEST SNOWFALL AMOUNTS ACROSS THE STATE. PROBABILITIES
FOR 12 INCHES OR MORE ARE SOLIDLY 70-100% ACROSS THE FORECAST AREA,
WITH THE PROBABILITY FOR 24 INCHES OR MORE RANGING FROM 30-60%.
HOWEVER, IF THE SLIGHT NORTHERLY TREND CONTINUES, THE SOUTHERN
PORTIONS OF THE FORECAST AREA COULD BEGIN TO SEE SOME WARMER AIR
LIFT INTO THE AREA, CAUSING SLEET OR FREEZING RAIN TO MIX INTO THE
AREA, WHICH WOULD LOWER SNOWFALL AMOUNTS IN THOSE AREAS. IN ADDITION
TO THE VERY HIGH SNOWFALL AMOUNTS, STRONG WINDS WILL ACCOMPANY THIS
SYSTEM, WITH THE PROBABILITY FOR WIND GUSTS EXCEEDING 35 MPH OVER
80% FOR MOST OF THE AREA. GIVEN THESE SNOWFALL AMOUNTS AND STRONG
WINDS, CONFIDENCE IS INCREASING FOR THE LIKELIHOOD OF
BLIZZARD/WHITEOUT CONDITIONS. THE MAIN QUESTION WILL BE HOW
WIDESPREAD THESE CONDITIONS WILL BE AND THE EXACT STORM TRACK.
ALL THAT BEING SAID, AFTER COLLABORATION WITH SURROUNDING OFFICES,
IT WAS DECIDED THERE WAS ENOUGH CONFIDENCE AND A STRONG
ENOUGH/CONSISTENT SIGNAL TO ISSUE THE WINTER STORM WATCH FOR THE
ENTIRE AREA FROM SATURDAY EVENING THROUGH MONDAY AFTERNOON FOR THIS
SYSTEM. NOW, IS THE TIME TO MAKE ALTERNATIVE PLANS AS TRAVEL WILL BE
EXTREMELY DIFFICULT TO IMPOSSIBLE DURING THIS TIME PERIOD.
AVIATION
FOR 18Z TAF ISSUANCE
ISSUED AT 139 PM CDT THU MAR 12 2026
GOOD FLYING CONDITIONS ARE EXPECTED TO CONTINUE THROUGH EARLY THIS
EVENING AHEAD OF A STRONG CLIPPER SYSTEM EXPECTED TO CAUSE IMPACTS
FOR THE REMAINDER OF THIS TAF PERIOD. IFR/LIFR CIGS AND VSBYS WILL
ACCOMPANY THE CLIPPER SYSTEM WITH SNOW BEING THE MAIN
PRECIPITATION TYPE, BUT SOME RAIN WILL MIX IN WITH THE SNOW AT
TIMES ACROSS CENTRAL AND EAST-CENTRAL WI. DECIDED TO INCLUDE RASN
FOR A PERIOD TONIGHT INTO FRIDAY MORNING AT ATW/GRB/MTW, WHERE
CONFIDENCE IS HIGHEST. SNOW RATES WILL BE FAIRLY HIGH ACROSS THE
NORTH, WHICH MAY IMPACT GROUND OPERATIONS FOR TERMINALS IN THIS
AREA SUCH AS RHI. ADDITIONAL SCATTERED SNOW SHOWERS ARE POSSIBLE
THROUGHOUT FRIDAY MORNING AS THE CLIPPER SYSTEM IS EXITING, WHICH
MAY CAUSE BRIEF DROPS IN VISIBILITY. DID NOT SPECIFY THESE SNOW
SHOWERS IN THIS TAF ISSUANCE AS CONFIDENCE IN LOCATION IS
UNCERTAIN.
STRONG WINDS WILL ACCOMPANY THIS SYSTEM, WITH GUSTS UP TO 30 TO 40
KNOTS EXPECTED TO REACH THE SURFACE AT TIMES OVERNIGHT. THE
HIGHEST WIND GUSTS ARE EXPECTED ACROSS THE EAST-CENTRAL WI TAF
SITES LATE THIS EVENING, AND ACROSS THE CENTRAL AND EAST-CENTRAL
WI TAF SITES FRIDAY MORNING. SOUTHEAST WINDS ARE EXPECTED AT THE
START OF THE TAF PERIOD, TURNING WEST/NORTHWEST BY FRIDAY MORNING.
ADDITIONALLY, STRONG WINDS ALOFT WILL CREATE A PERIOD OF LLWS AT
ALL TAF SITES MAINLY BETWEEN 03Z-12Z FRI.
GRB WATCHES/WARNINGS/ADVISORIES
WINTER STORM WARNING UNTIL 1 PM CDT FRIDAY FOR WIZ005-010>013-
018>021-073.
WINTER STORM WATCH FROM SATURDAY EVENING THROUGH MONDAY
AFTERNOON FOR WIZ005-010>013-018>022-030-031-035>040-045-048>050-
073-074.
WINTER WEATHER ADVISORY FROM 10 PM THIS EVENING TO 1 PM CDT
FRIDAY FOR WIZ022-074.
WINTER WEATHER ADVISORY UNTIL 1 PM CDT FRIDAY FOR WIZ030-031.
WIND ADVISORY FROM MIDNIGHT TONIGHT TO 6 PM CDT FRIDAY FOR
WIZ035>040-045-048>050.
DISCUSSION.....KRUK
AVIATION.......KRUK
CLICK HERE TO GO TO PREVIOUS BULLETINS.
Main Text Page