Thunderstorms developed in unstable air ahead of an approaching surface front. Some of the storms downed trees and power lines and produced hail to half dollar size.
Every event with a place to put it. Tap one for its entry below.
Deaths and injuries are direct and indirect together, as the offices filed them. Damage is property and crops in the dollars of the year, not adjusted for inflation, and only where an office estimated it.
The episode as NWS GRB wrote it up.
Thunderstorms developed in unstable air ahead of an approaching surface front. Some of the storms downed trees and power lines and produced hail to half dollar size.
The local office's own words before the first event, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.
NWS Green Bay, WI wrote its last area forecast discussion before the first event at May 28, 11:51 AM CST, 1 hour 44 minutes earlier.
AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE GREEN BAY WI 1251 PM CDT MON MAY 28 2012 UPDATED AVIATION PORTION FOR 18Z TAF ISSUANCE .SHORT TERM... TODAY THROUGH TUESDAY. A COLD FRONT OVER MINNESOTA WILL BRING THE THREAT OF SHOWERS AND THUNDERSTORMS TODAY AS IT MOVES SLOWLY EAST. LOW LEVEL CONVERGENCE ALONG THE FRONT WEAKENS WITH TIME AND THERE IS ACTUALLY WEAK COLD ADVECTION BY THE END OF THE DAY. THESE FACTORS ARGUE AGAINST SIGNIFICANT PRECIPITATION BUT THE SYSTEM DOES HAVE SOMETHING GOING FOR IT...THE RIGHT ENTRANCE REGION OF A VIGOROUS UPPER JET IS FORECAST TO MOVE ACROSS THE AREA THIS AFTERNOON. ALL IN ALL THE BEST DYNAMICS LOOK TO BE IN THE EASTERN HALF OF THE FORECAST AREA THIS AFTERNOON. THE SEVERE THREAT WILL DEPEND ON HOW MUCH SURFACE HEATING WE GET AND HOW MUCH LOW LEVEL MOISTURE THERE IS. THE MAIN SEVERE WEATHER THREAT WOULD BE WINDS AND HAIL. HIGHS TODAY SHOULD BE WARMER THAN YESTERDAY OVER ALL BUT THE SOUTHERNMOST COUNTIES. THE FRONT MOVES THROUGH TONIGHT BUT MAIN PUSH OF COLD AIR LAGS BEHIND QUITE A BIT. SOME LEFTOVER SHOWERS POSSIBLE IN THE EAST DURING THE EVENING. LOWS SHOULD BE A FEW DEGREES ABOVE NORMAL FOR THIS TIME OF THE YEAR. BLUSTERY AND COOLER TUESDAY AS 850MB TEMPERATURES FALL THROUGH THE SINGLE NUMBERS DURING THE DAY. THE LEFT EXIT REGION OF AN UPPER JET IS FORECAST TO MOVE ACROSS NORTHERN WISCONSIN AND MIGHT BE SUFFICIENT TO PRODUCE SOME SCATTERED SHOWERS. .LONG TERM...TUESDAY NIGHT THROUGH SUNDAY. COLD AIR MOVING OVER LAKE SUPERIOR IN CYCLONIC FLOW BEHIND A DEPARTING SURFACE COLD FRONT AND LOW WILL KEEP A CHANCE OF SOME SHOWERS ACROSS NORTH CENTRAL WISCONSIN ON TUESDAY NIGHT. EVEN WITHOUT PRECIPITATION...THERE SHOULD BE ENOUGH CLOUDS AND WIND TO HOLD TEMPERATURES UP AND KEEP FROST FROM DEVELOPING. SKIES SHOULD BEGIN TO CLEAR ON WEDNESDAY WITH SURFACE HIGH PRESSURE AND A WEAK UPPER RIDGE OVER WISCONSIN. A SYSTEM APPROACHING FROM THE PLAINS WILL BRING AN INCREASE IN CLOUDS TO THE SOUTHERN PART OF THE AREA ON WEDNESDAY NIGHT. A COLD AIRMASS...LIGHT WINDS AND PARTLY CLOUDY SKIES SHOULD ALLOW AT LEAST PATCHY FROST TO DEVELOP ACROSS MUCH OF NORTHERN WISCONSIN. THE MAIN ISSUE FROM THURSDAY THROUGH SUNDAY IS RUN-TO-RUN MODEL CONSISTENCY. THE LATEST MODEL RUNS LOOK WETTER THAN THEY DID 24 HOURS AGO...SO HAVE OPTED TO LEAVE THE BLENDED MODEL SOLUTION ALONE DURING THIS PART OF THE FORECAST. THIS APPROACH YIELDS AREAS OF AT LEAST SLIGHT CHANCE POPS IN THE GRIDS FOR MOST PERIODS. CLOUDS SHOULD GENERALLY HELP TO KEEP LOW TEMPERATURES FROM FALLING BELOW NORMAL. HIGHS WILL BE ON THE COOL SIDE FOR THE END OF THE WORK WEEK...BEFORE WARMING UP OVER THE WEEKEND. && .AVIATION...SCATTERED THUNDERSTORMS WILL MOVE ACROSS NORTH CENTRAL AND NORTHEAST WISCONSIN DURING THE REMAINDER OF THE AFTERNOON INTO EARLY THIS EVENING. SOME OF THESE STORMS COULD PRODUCE LARGE HAIL AND DAMAGING WINDS IN EXCESS OF 50 KNOTS. VFR CONDITIONS SHOULD PREVAIL AFTER THE STORMS EXIT THE REGION. BETWEEN 04Z AND 07Z... SOME MODEL GUIDANCE SUGGEST THAT THERE IS SOME POTENTIAL FOR A PERIOD OF GUSTY WINDS OF 15 TO 25 KNOTS. THESE WINDS WILL CONTINUE FOR MOST THE REMAINDER OF THE NIGHT...ALTHOUGH COULD BE A PERIOD JUST BEFORE OR AROUND SUNRISE THAT THE WINDS DECOUPLE FOR A BRIEF PERIOD. WINDY CONDITIONS EXPECTED ON TUESDAY WITH GUSTS TO AROUND 30 KNOTS POSSIBLE. MVFR CIGS EXPECTED TO MOVE INTO NORTH CENTRAL WISCONSIN TUESDAY. SCATTERED TO ISOLATED SHOWERS EXPECTED NORTH OF A MERRILL TO MARINETTE LINE ON TUESDAY...ESPECIALLY DURING THE AFTERNOON HOURS. ECKBERG && .MARINE...SMALL CRAFT WILL BE ISSUED FOR MEMORIAL DAY...FROM 10 AM TO 6 PM. GUSTY SOUTH/SOUTHWEST WINDS CAN BE EXPECTED WITH SOME GUSTS TO AROUND 25 KNOTS BY LATE MORNING THROUGH MUCH OF THE AFTERNOON. && .GRB WATCHES/WARNINGS/ADVISORIES... NONE. &&
HAZARDOUS WEATHER OUTLOOK NATIONAL WEATHER SERVICE GREEN BAY WI 1137 AM CDT MON MAY 28 2012 WIZ005-010>013-018>022-030-031-035>040-045-048>050-073-074-291645- VILAS-ONEIDA-FOREST-FLORENCE-NORTHERN MARINETTE-LINCOLN-LANGLADE- MENOMINEE-NORTHERN OCONTO-DOOR-MARATHON-SHAWANO-WOOD-PORTAGE- WAUPACA-OUTAGAMIE-BROWN-KEWAUNEE-WAUSHARA-WINNEBAGO-CALUMET- MANITOWOC-SOUTHERN MARINETTE-SOUTHERN OCONTO- 1137 AM CDT MON MAY 28 2012 THIS HAZARDOUS WEATHER OUTLOOK IS FOR NORTH CENTRAL AND NORTHEAST WISCONSIN. .DAY ONE...THIS AFTERNOON AND TONIGHT THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS THIS AFTERNOON. SOME OF THE STRONGER STORMS COULD PRODUCE DAMAGING WINDS AND LARGE HAIL. THE GREATEST THREAT OF SEVERE STORMS WILL BE FROM 3 PM TO 7 PM. .DAYS TWO THROUGH SEVEN...TUESDAY THROUGH SUNDAY MUCH COOLER AIR WILL ARRIVE DURING THE MIDDLE OF THE WEEK. FROST IS POSSIBLE IN NORTH CENTRAL AND FAR NORTHEAST WISCONSIN EARLY THURSDAY MORNING. .SPOTTER INFORMATION STATEMENT... SPOTTER ACTIVATION MAY BE NEEDED THIS AFTERNOON. LMZ521-522-541>543-291645- THE BAY OF GREEN BAY SOUTH OF A LINE FROM CEDAR RIVER MI TO ROCK ISLAND PASSAGE-LAKE MICHIGAN FROM WASHINGTON ISLAND TO SHEBOYGAN- 1137 AM CDT MON MAY 28 2012 THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF NORTHWEST LAKE MICHIGAN AND THE WATERS OF GREEN BAY. .DAY ONE...THIS AFTERNOON AND TONIGHT THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS WITH STRONG WINDS AND HAIL BETWEEN 3 PM AND 8 PM. EVEN IF SEVERE STORMS DO NOT OCCUR... GUSTY SOUTHWEST WINDS AND BUILDING WAVES MAY POSE A HAZARD TO SMALL CRAFT TODAY. .DAYS TWO THROUGH SEVEN...TUESDAY THROUGH SUNDAY STRONG WEST WINDS MAY CREATE A HAZARD TO SMALL CRAFT ON TUESDAY.
PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE GREEN BAY WI
227 PM CDT MON MAY 28 2012
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE....
..REMARKS..
0225 PM HAIL SYMCO 44.51N 88.90W
05/28/2012 M0.25 INCH WAUPACA WI TRAINED SPOTTER
&&
BERSCHSPECIAL WEATHER STATEMENT NATIONAL WEATHER SERVICE GREEN BAY WI 231 PM CDT MON MAY 28 2012 WIZ013-019>021-031-073-074-282030- LANGLADE-MENOMINEE-NORTHERN MARINETTE COUNTY-NORTHERN OCONTO COUNTY-SHAWANO-SOUTHERN MARINETTE COUNTY-SOUTHERN OCONTO COUNTY- 231 PM CDT MON MAY 28 2012 ...STRONG THUNDERSTORMS IN MENOMINEE AND OCONTO COUNTIES... AT 226 PM CDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A RAPIDLY DEVELOPING THUNDERSTORM 9 MILES NORTH OF SHAWANO...MOVING NORTHEAST AT 45 MPH. ANOTHER STRONG STORM WAS LOCATED IN CENTRAL OCONTO COUNTY NEAR BREED. THESE STORMS WILL AFFECT EASTERN MENOMINEE AND CENTRAL OCONTO COUNTIES THROUGH 315 PM. WIND GUSTS TO 40 MPH... HAIL UP TO PENNY SIZE AND HEAVY RAINFALL ARE ANTICIPATED. GUSTY WINDS MAY CAUSE SMALL OBJECTS SUCH AS TRASH BINS TO BLOW AROUND. STAY AWAY FROM HIGH OBJECTS OUTDOORS SUCH AS TREES. SEEK SHELTER IN A STURDY STRUCTURE UNTIL THIS STORM HAS PASSED. KIECKBUSCH
The Green Bay radar (KGRB), 115 km away, was scanning. The volume nearest the first event began at 19:35 UTC.
6 hail, 5 thunderstorm wind. Local standard time, as filed.
Quarter size hail was reported at Stevens Point. The time of this event was estimated based on radar data.
Penny size hail was observed by a spotter in Clintonville.
Wind gusts estimated at 65 mph downed trees and power lines in Crivitz between 3:00 pm CDT and 3:10 pm CDT.
Thunderstorm wind gusts to at least 60 mph downed a pair of trees and several branches near Split Rock.
Quarter size hail was observed by a spotter in Split Rock.
Thunderstorm wind gusts, estimated at 60 mph, downed a tree and several power lines in Tigerton.
Half dollar size hail fell in Tigerton.
A Skywarn spotter observed nickel size hail as thunderstorms moved through Nekoosa.
Thunderstorm winds, estimated at 65 mph, downed several trees northwest of Shawano.
Nickel size hail, torrential rain and wind gusts estimated at 45 mph were reported by a spotter in Clintonville as thunderstorms moved through the area.
A spotter, southeast of Hortonville, reported a measured wind gust of 67 mph as thunderstorms moved through the area.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Wisconsin in 2012Every state in 2012This day in weather historyWarnings in Wisconsin, May 2012
NOAA National Centers for Environmental Information, Storm Events Database, compiled from the National Weather Service’s monthly Storm Data. Complete through 2026-06; NCEI adds each month about 75 days after it ends and revises past years a few times a year. Rebuilt 2026-09-24. Each event’s entry at NCEI: 381895, 381896, 381901, 381902, 381897, 381904, 381898, 381918, 381907, 381899, 381910.