Very moist and unstable air interacted with an approaching cold front and produced severe thunderstorms. Some of the storms had wind gusts to 68 mph that downed trees and power lines, golf ball size hail, and heavy rain.
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.
Very moist and unstable air interacted with an approaching cold front and produced severe thunderstorms. Some of the storms had wind gusts to 68 mph that downed trees and power lines, golf ball size hail, and heavy rain. Lightning from the storms struck a house in Brown County, causing it to fill with smoke. The storms also knocked out power to about 4,500 customers in Manitowoc County and dropped 2 to 3 inches of rain in parts of east-central Wisconsin.
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 Jul 25, 6:07 PM CST, 23 minutes earlier.
AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE GREEN BAY WI 707 PM CDT WED JUL 25 2012 UPDATED AVIATION PORTION FOR 00Z TAF ISSUANCE .UPDATED... CONVECTION NOW TRYING TO GET GOING ALONG BOUNDARY FROM NEAR SUE TO STE AS CONVERGENCE HAS INCREASED ALONG FRONT. QUESTION IS CAN ANYTHING GET GOING AS WE BEGIN TO COOL THIS EVENING. HAVE ADJUSTED GRIDS TO DOWNPLAY ACTIVITY NORTH...ADDED SEVERE HEADLINES FOR SOUTH. .SHORT TERM...TONIGHT AND THURSDAY THUNDERSTORMS ARE EXPECTED TO RAPIDLY DEVELOP DURING THE REMAINDER OF THE AFTERNOON AND THEN MOVE ACROSS THE REGION EARLY THIS EVENING. MESOANALYSIS INDICATED ATMOSPHERE BECOMING VERY UNSTABLE WITH SURFACE BASED CAPES OF 1500 TO 2500 J/KG. DISTURBANCE MOVING ACROSS MINNESOTA WILL HELP TRIGGER THE CONVECTION AS THERE IS A VERY WARM LAYER ALOFT TO OVERCOME. WIND SHEAR SUFFICIENT FOR ROTATING SUPER CELLS AT THE BEGINNING OF THE EVENT...THEN SHOULD EVOLVE INTO A LINE. STORMS SHOULD EXIT THE REGION BY MID TO LATE EVENING ACROSS THE SOUTHEAST. BEHIND THE FRONT...LOW CLOUDS AND FOG WILL BE LINGERING ACROSS THE REGION AFTER MIDNIGHT. ATTENTION THEN TURNS TO NEXT SYSTEM DROPPING FROM THE NORTHWEST THURSDAY AFTERNOON. WIND SHEAR OF 35 TO 45 KNOTS NOTED OFF THE WRF MODEL THURSDAY AFTERNOON TO SUPPORT THE SLIGHT RISK OF SEVERE THUNDERSTORMS. MODIFIED SOUNDINGS INDICATED WINDEX VALUES AROUND 45 KNOTS TO SUPPORT THE POSSIBILITY OF STRONG OR DAMAGING WINDS. DID NOT STRAY FAR FROM GUIDANCE TONIGHT OR THURSDAY. .LONG TERM...THURSDAY NIGHT THROUGH NEXT TUESDAY. THE LATEST GFS ENSEMBLE MEAN INDICATES THAT THE UPPER TROUGH WILL EXIT NORTHEAST WISCONSIN LATE FRIDAY...AND THEN WISCONSIN WILL RESIDE WITHIN NW FLOW ALOFT BETWEEN MID-LEVEL RIDGING OVER THE ROCKIES AND TROUGHING OVER THE EAST COAST. LOCATED WITHIN THE WESTERLIES...OUR REGION WILL BE SUSCEPTIBLE TO WEAK SHORTWAVE IMPULSES THAT WILL BE CAPABLE OF PRODUCING SCT SHOWERS AND STORMS...AND ARE ALSO TOO SMALL TO BE RESOLVE BY THE MODELS. RATHER THAN CLUTTER THE EXTENDED FORECAST WITH SMALL CHANCE POPS TO ACCOUNT FOR THE POSSIBILITY OF THESE WEAK RIPPLES...WILL TRY TO REMOVE POPS WHERE POSSIBLE. THURSDAY NIGHT THROUGH FRIDAY NIGHT...A WEAKENING SHORTWAVE TROUGH WILL BE SWINGING ACROSS NORTHERN WISCONSIN THURSDAY NIGHT THROUGH FRIDAY MORNING. LOCATION OF A MODEST POCKET OF -DIVQ AND MID-LEVEL CONVERGENCE SUGGESTS THE HIGHEST POPS WILL RESIDE OVER THE NORTHERN FORECAST AREA. THOUGH THE WAVE WILL BE EXITING BY AROUND MIDDAY FRIDAY...MODELS POINT TOWARD PLENTY OF MOISTURE LINGERING ALONG AN 850MB TROUGH AS IT SHIFTS SOUTH ACROSS THE FORECAST AREA EARLY TO MID FRIDAY AFTERNOON. THE INHERITED POPS HANDLE THIS WELL...AND SHOW THE HIGHEST POTENTIAL FOR PRECIP OVER NE WISCONSIN WHERE CONVERGENCE WILL BE MAXIMIZED. WILL ONLY TWEAK POPS FOR COSMETIC PURPOSES. HIGH PRESSURE THEN BUILDS IN FOR FRIDAY NIGHT. PLENTY OF MOISTURE LOOKS TO REMAIN IN THE BOUNDARY LAYER...SUGGESTING FOG IS A POSSIBILITY. WILL ADD IT TO THE NORTH. REST OF THE FORECAST...HIGH PRESSURE WILL MOVE ACROSS THE AREA SATURDAY INTO SATURDAY NIGHT....WHICH SHOULD LEAD TO MOSTLY CLEAR SKIES AND SEASONABLE TEMPERATURES. THE FIRST SHORTWAVE IN NORTHWEST FLOW IS PROGGED TO ARRIVE ON SUNDAY. RETURN FLOW AHEAD OF THE SHORTWAVE WILL TRY TO MOVE INTO CENTRAL WISCONSIN THOUGH THINK THE GFS IS TOO AGGRESSIVE. WILL KEEP THE POSSIBILITY OF PRECIP IN THE FORECAST FOR SUNDAY. THE ALLBLEND SPREADS POPS AROUND TO VARIOUS DEGREES OTHER PERIODS...BUT SUNDAY LOOKS TO BE THE BEST CHANCE SO FAR. TEMPERATURES TO REMAIN ABOVE NORMAL OVER THE PERIOD. && .AVIATION...TONIGHT AND WEDNESDAY. MAIN CONCERN FOR AVIATION INTEREST WILL BE THUNDERSTORMS CHANCES FOR THE REMAINDER OF THE AFTERNOON AND EVENING...THEN LOW CLOUD AND FOG BEHIND THE COLD FRONT LATER THIS EVENING INTO THURSDAY MORNING. AS FOR CONVECTION...STORMS BEGINNING MOVE INTO TAF SITES IN THE FOX VALLY. SOME OF THESE STORMS MAY BE SEVERE WITH DAMAGING WINDS OF 50 KNOTS OR GREATER AND WILL PRODUCE BRIEF VISIBILITIES BELOW ONE MILE IN HEAVY RAIN. STORMS EXPECTED TO BE EAST OF AREA BY 03Z. A SECONDARY WIND SHIFT...BRINGING MORE ORGAINIZED SHOWERS/STORMS TO THE NORTH. LATER TONIGHT AFTER THE RAIN...LOW CLOUDS AND FOG ARE EXPECTED ACROSS MUCH OF THE AREA FROM LATE THIS EVENING INTO THURSDAY MORNING. THE FOG SHOULD DISSIPATE BY 15Z. MVFR/IFR/LIFR/VLIFR CIGS SHOULD GRADUALLY IMPROVE TO VFR CONDITIONS BY 15-17Z. ON THURSDAY AFTERNOON AND EVENING...AN UPPER LEVEL DISTURBANCE WILL BRING A CHANCE OF SHOWERS AND THUNDERSTORMS TO THE AREA. BEST CONCENTRATION OF STORMS WILL BE NORTH AND WEST OF GREEN BAY AND THE FOX CITIES DURING THE AFTERNOON...THEN ACROSS EAST CENTRAL AND NORTHEAST WISCONSIN THURSDAY EVENING. SOME OF THE STORMS WILL BE CAPABLE OF PRODUCING DAMAGING WINDS AND LARGE HAIL. AT THIS POINT TSTMS JUST MENTIONED IN RHI FOR THU. TE && .GRB WATCHES/WARNINGS/ADVISORIES... HEAT ADVISORY UNTIL 7 PM CDT THIS EVENING FOR WIZ045-048-049. &&
HAZARDOUS WEATHER OUTLOOK NATIONAL WEATHER SERVICE GREEN BAY WI 249 PM CDT WED JUL 25 2012 WIZ005-010>013-018>022-030-031-035>040-045-048>050-073-074-262000- 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- 249 PM CDT WED JUL 25 2012 THIS HAZARDOUS WEATHER OUTLOOK IS FOR NORTH CENTRAL AND NORTHEAST WISCONSIN. .DAY ONE...TONIGHT THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS ALL OF NORTH CENTRAL AND NORTHEAST WISCONSIN THIS AFTERNOON AND EARLY THIS EVENING. THE GREATEST RISK OF SEVERE THUNDERSTORMS SHOULD OCCUR ACROSS PARTS OF CENTRAL AND EAST CENTRAL WISCONSIN... INCLUDING THE FOX VALLEY AND LAKESHORE AREAS BETWEEN 5 AND 9 PM. DAMAGING WINDS AND TORRENTIAL RAINFALL SHOULD BE THE PRIMARY CONCERNS. LARGE HAIL IS ALSO POSSIBLE WITH THE STRONGER STORMS. AFTERNOON HEAT INDICES WILL EXCEED 100 DEGREES FROM WAUTOMA TO OSHKOSH TO CHILTON THIS AFTERNOON. A HEAT ADVISORY IS IN EFFECT UNTIL 7 PM. .DAYS TWO THROUGH SEVEN...THURSDAY THROUGH WEDNESDAY THERE IS A CHANCE OF THUNDERSTORMS THURSDAY AFTERNOON THROUGH FRIDAY. A FEW STORMS MAY BECOME SEVERE LATE THURSDAY AFTERNOON INTO FRIDAY EVENING...AND LARGE HAIL AND DAMAGING WIND GUSTS WILL BE THE MAIN THREATS. THERE IS ANOTHER CHANCE OF THUNDERSTORMS ON SUNDAY INTO SUNDAY NIGHT. HOWEVER IT IS TOO EARLY TO DETERMINE THE SEVERE WEATHER POTENTIAL WITH THESE STORMS. .SPOTTER INFORMATION STATEMENT... FORMAL SPOTTER ACTIVATION IS LIKELY THIS AFTERNOON AND THIS EVENING... ESPECIALLY ACROSS CENTRAL AND NORTHEAST WISCONSIN. LMZ521-522-541>543-262000- THE BAY OF GREEN BAY SOUTH OF A LINE FROM CEDAR RIVER MI TO ROCK ISLAND PASSAGE-LAKE MICHIGAN FROM WASHINGTON ISLAND TO SHEBOYGAN- 249 PM CDT WED JUL 25 2012 THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF NORTHWEST LAKE MICHIGAN AND THE WATERS OF GREEN BAY. .DAY ONE...TONIGHT THUNDERSTORMS ARE LIKELY AGAIN LATER THIS AFTERNOON AND EVENING THAT WOULD POSE A SERIOUS RISK TO SMALL CRAFT. THESE STORMS WILL LIKELY PRODUCE STRONG WINDS...TORRENTIAL RAINS THAT WILL REDUCE VISIBILITIES BELOW ONE MILE...AND HIGH WAVES. .DAYS TWO THROUGH SEVEN...THURSDAY THROUGH WEDNESDAY THERE IS A CHANCE OF THUNDERSTORMS AT TIMES FROM LATE THURSDAY THROUGH FRIDAY. AN ISOLATED STORM MAY BECOME SEVERE LATE THURSDAY AFTERNOON INTO FRIDAY EVENING. OTHERWISE...SEVERE WEATHER IS NOT EXPECTED. THUNDERSTORMS ARE ALSO POSSIBLE FROM SUNDAY INTO SUNDAY NIGHT. RE/MPC
PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE GREEN BAY WI
430 PM CDT WED JUL 25 2012
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE....
..REMARKS..
0430 PM HEAVY RAIN WINCHESTER 46.21N 89.90W
07/25/2012 M1.80 INCH VILAS WI CO-OP OBSERVER
RAINFALL FROM LAST NIGHT AND THIS MORNING.
&&
ECKBERGPRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE GREEN BAY WI
643 PM CDT WED JUL 25 2012
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE....
..REMARKS..
0642 PM HAIL 2 S MANITOWOC 44.05N 87.66W
07/25/2012 M0.25 INCH MANITOWOC WI PUBLIC
&&
ASHLEYWPRELIMINARY LOCAL STORM REPORT...CORRECTED
NATIONAL WEATHER SERVICE GREEN BAY WI
645 PM CDT WED JUL 25 2012
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE....
..REMARKS..
0642 PM HAIL 2 S MANAWA 44.43N 88.91W
07/25/2012 M0.25 INCH WAUPACA WI PUBLIC
CORRECTED FOR CITY
&&
ASHLEYWSPECIAL WEATHER STATEMENT NATIONAL WEATHER SERVICE GREEN BAY WI 718 PM CDT WED JUL 25 2012 WIZ038>040-049-050-260130- OUTAGAMIE-BROWN-KEWAUNEE-CALUMET-MANITOWOC- INCLUDING THE CITIES OF...APPLETON...GREEN BAY...ALGOMA... CHILTON...TWO RIVERS 718 PM CDT WED JUL 25 2012 ...SCATTERED THUNDERSTORMS MOVING ACROSS NORTHEAST WISCONSIN EARLY THIS EVENING... AT 715 PM...DOPPLER RADAR INDICATED SCATTERED SHOWERS AND THUNDERSTORMS EXTENDING FROM NEAR APPLETON TO SHIOCTON TO BLACK CREEK EAST TO NEAR MISHICOT AND NEAR ALGOMA. THE SHOWERS AND STORMS WERE MOVING TO THE EAST AROUND 40 MPH. THE STRONGEST STORMS WILL MOVE EASTERN OUTAGAMIE AND INTO BROWN COUNTY THROUGH 8 PM. THE STRONGEST STORMS WILL BE CAPABLE OF PRODUCING PENNY SIZE HAIL...RAINFALL RATES OF 1 TO 2 INCHES PER HOUR...WIND GUSTS TO 50 MPH AND FREQUENT CLOUD TO GROUND LIGHTNING STRIKES. THE HIGH RAINFALL RATES WILL CAUSE URBAN STREET FLOODING AND PONDING OF WATER ON AREA ROADWAYS. ECKBERG
The Green Bay radar (KGRB), 15 km away, was scanning. The volume nearest the first event began at 00:30 UTC.
5 thunderstorm wind, 2 hail, 1 lightning. Local standard time, as filed.
Five residents of a house had to be evacuated when it filled with smoke after being struck by lightning.
Thunderstorm winds downed power lines at the intersection of Monroe Street and Willow Street in Little Chute.
Thunderstorm winds produced extensive damage at 141 Speedway southeast of Maribel. Track vehicles were damaged, covers were torn from bleachers, some walls were blown out, billboards were knocked down, and doors were ripped from their hinges. The time of this event was estimated based on radar data.
Thunderstorms produced a wind gust to 60 mph and half inch hail at Valders.
Thunderstorms produced a wind gust to 68 mph at Manitowoc County Airport. The strong winds knocked down a few trees in the city of Manitowoc.
Thunderstorms produced a wind gust estimated at 65 mph that downed trees, one of which fell on a car, as they moved through Two Rivers. The storms also produced dime size hail as they passed.
Quarter size hail fell at Two Rivers.
A thunderstorm produced golf ball size hail and strong winds at Two Rivers. The winds downed a flag pole and threw chairs across a yard.
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, July 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: 404615, 402204, 408621, 402206, 402208, 402211, 402194, 402196.