A line of thunderstorms crossed southern Wisconsin during the morning hours of June 21st. A segment of the line briefly bowed out over portions of Sauk, Iowa and Lafayette counties, causing wind damage to trees and power lines in northwest Iowa County near Avoca.
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 MKX wrote it up.
A line of thunderstorms crossed southern Wisconsin during the morning hours of June 21st. A segment of the line briefly bowed out over portions of Sauk, Iowa and Lafayette counties, causing wind damage to trees and power lines in northwest Iowa County near Avoca. Vigorous synoptic forcing, especially strong, sloped frontogenesis from the surface up to 700 mb, accompanied a short wave trough through the region that drove a complex of strong to severe thunderstorms across Minnesota into southern 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 Milwaukee, WI wrote its last area forecast discussion before the first event at Jun 21, 2:08 AM CST, 4 hours 47 minutes earlier.
AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE MILWAUKEE/SULLIVAN WI 308 AM CDT FRI JUN 21 2013 .TODAY AND TONIGHT...FORECAST CONFIDENCE MEDIUM. THIS WARM...MOIST AND UNSTABLE SOUTHWESTERLY FLOW REGIME IS TYPICALLY DIFFICULT TO RESOLVE DETAILED CONVECTIVE TRENDS BEYOND ABOUT 12HRS. CONVECTION BEYOND 12HRS DEPENDS HIGHLY ON THE BEHAVIOR OF CONVECTION IN THE PRECEDING 12HRS. FOR INSTANCE...ALL THE HI RESOLUTION SHORT RANGE MODELS ARE HAVING DIFFICULTY WITH THE CONVECTION OVER MN EARLY THIS MORNING. EARLIER MODEL RUNS DEVELOPED THIS INTO A BIG BOW ECHO THAT RACED ACROSS THE FORECAST AREA AROUND 12Z. THE REALITY IS THAT IT IS STAYING UP TO THE NORTH MUCH LONGER AND MAY END UP JUST SKIRTING THE NORTHERN FORECAST AREA BEFORE DIMINISHING WITH TYPICAL DIURNAL TRENDS. THE TURN TO THE SOUTHEAST NEEDS THE COLD POOL DYNAMICS TO GET ORGANIZED AND THAT APPEARS TO BE HAPPENING AROUND 07Z THIS MORNING. EACH HRRR RUN HAS BEEN BACKING OFF ON THE SPEED AND OVERALL DEVELOPMENT. THE NOSE OF THE LOW LEVEL JET AND BEST INSTABILITY ARE TO THE WEST AND NORTH...BUT WILL LEAN NORTHEAST INTO THE AREA TODAY. THE MODELS CONTINUE TO BE TOO BULLISH ON SFC MOISTURE. FOR NOW...THERE DOES SEEM TO BE A CONSENSUS THAT WE WILL LIKELY SEE THE MN CONVECTION ROLL ACROSS THE AREA THIS MORNING AS THE LOW LEVEL JET AND MOISTURE LEAN INTO THE AREA. THIS SHOULD LAY OUT A LOW LEVEL BAROCLINIC ZONE THAT COULD BE THE FOCUS FOR MORE CONVECTION LATER THIS AFTERNOON. WE SHOULD SEE ANOTHER MCS DEVELOP OUT IN THE PLAINS THIS AFTERNOON AND ROLL INTO THE CWA LATER TONIGHT. SO LONG STORY SHORT...LOOK FOR MORNING CONVECTION TO DIMINISH THIS AFTERNOON WITH ANOTHER ROUND LATE TONIGHT INTO SATURDAY MORNING. TEMPS MIGHT BE HELD DOWN A BIT TODAY IF WE ARE SLOW TO SCOUR OUT THE MORNING CONVECTIVE DEBRIS. TEMPS WON/T DROP TOO FAR TONIGHT AS WE ARE SOLIDLY IN THE WARM SECTOR. SATURDAY THROUGH SUNDAY NIGHT...FORECAST CONFIDENCE MEDIUM TO HIGH. PRECIP CHANCES CONTINUE TO EXIST EARLY ON THIS PERIOD EVEN THOUGH 500 HPA SHORT WAVE TROUGHS TRAVERSE MAINLY TO OUR NORTH AND WEST. CWA CONTINUES TO LIE UNDER A MID-LEVEL RIDGE WITH SHORT WAVE TROUGHS RIDING THROUGH. THE NOCTURNAL LLJ MAINLY FOCUSES ON SOUTHWEST AND WEST CENTRAL WISCONSIN...PEAKING SATURDAY NIGHT. MODELS DO SHOW LOW-LEVEL WAA AT THIS TIME...BUT WAA MORE PERSISTENT AND STRONGER OUTSIDE THE CWA. FURTHER...ALTHOUGH SOME SYNOPTIC LIFT WILL BE PRESENT IN THE PERIOD...THE THERMODYNAMIC ENVIRONMENT WILL NOT BE THAT PRIMED. BUFKIT SOUNDINGS AND LOW-LEVEL THERMO ENVIRONMENT SHOW A CAPPED ENVIRONMENT COINCIDING WITH LOW-LEVEL THERMAL RIDGE. THIS COULD POTENTIALLY LIMIT OUR THUNDER CHANCES THIS WEEKEND. OTHERWISE...AMPLE MEAN LAYER INSTABILITY IN THE PERIOD WILL COMBINE WITH SUFFICIENT MOISTURE...ESPECIALLY CONSIDERING SFC DEW POINTS FCST IN THE UPPER 60S TO AROUND 70 DURING THE DAY SAT AND SUN. SHEAR WILL BE A LIMITING FACTOR THOUGH FOR ANY ORGANIZED DEVELOPMENT IN THE PERIOD. DEEP LAYER 0-6KM SHEAR IS ONLY AROUND 15-25 KTS. THIS SUGGEST ORDINARY THUNDERSTORMS AND SOME MULTICELL ORGANIZATION TYPE STORM MODES. SATURDAY IS EXPECTED TO GIVE THE CWA THE BEST CHANCE FOR CONVECTION GIVEN THE BETTER INSTABILITY AND PROXIMITY OF THE EFFECTIVE BOUNDARY. THOUGH GIVEN THE AFOREMENTIONED CAP AND THE UNCERTAIN POSITION OF THE BOUNDARY...CONTINUED WITH CHANCES ON SATURDAY. WARM AND ABOVE NORMAL HIGHS EXPECTED SATURDAY AND SUNDAY. MODEL CONSENSUS OF 925 HPA TEMPS ARE AROUND 25-27 C SAT AND 24-26 C SUN THAT CORRESPOND TO 89-93 F AND 87-91 F...RESPECTIVELY. NOTE...WILL HAVE TO WATCH APPARENT TEMPS/HEAT INDEX VALUES SUNDAY GIVEN THE MOIST SFC DEW POINTS IN THE UPPER 60S/AROUND 70 AND SFC HIGHS AROUND 90 IN PORTIONS OF THE CWA...AS HEAT INDEX VALUES REACH LOW AND MID 90S SAT AND WELL INTO THE MID AND UPPER 90S SUN. POTENTIAL RISK OF HEAT INDEX VALUES FURTHER SUBSTANTIATED BY LOOKING AT CIPS IMPACT BASED GUIDANCE\S PROBABILITY OF SFC HEAT INDEX VALUES EXCEEDING 95 F THAT HAS HIGH PROBS IN SOUTH CENTRAL AND SOUTHEAST WI. MONDAY THROUGH THURSDAY NIGHT...FORECAST CONFIDENCE MEDIUM. PERIOD CHARACTERIZED GENERALLY BY A MID-LEVEL ZONAL FLOW...THAT BREAKS DOWN LATE THURSDAY INTO FRIDAY AS A MORE AMPLIFIED PATTERN TAKES OVER. THE LATTER SHARED BY BOTH THE GFS AND ECMWF. VARIOUS S/W TROUGHS MOVE THROUGH THOUGH DIFFERENCES BETWEEN FEATURES AND TIMING MAKE FCST UNCERTAIN. THE GENERAL SW FLOW AND THERMAL ENVIRONMENT THOUGH SHOULD KEEP READINGS NEAR OR ABOVE THEIR SEASONAL NORMAL VALUES. SEASONAL NORMAL VALUES THIS TIME OF THE YEAR ARE USUALLY AROUND 81-82 TO 78-79 WEST TO EAST ACROSS THE CWA. BY THURSDAY INTO FRIDAY WITH A LONG WAVE TROUGH DIGGING INTO THE GREAT LAKES REGION...FLOW BECOMES MORE OUT OF THE NW-N AND HIGH TEMPERATURES BEGIN TRENDING DOWNWARD. && .AVIATION/12Z TAFS/...MAIN AVIATION CONCERN DURING THE PERIOD IS TIMING OF ANY CONVECTION...AND THAT WILL BE CHALLENGING. OVERALL...CONDITIONS SHOULD BE VFR. THE EXCEPTION WILL BE IN AND AROUND ANY THUNDERSTORMS WHERE VSBY AND CIGS COULD BRIEFLY DROP TO MVFR LEVELS. WE SHOULD SEE STORMS MOVE THROUGH THE AREA THIS MORNING...AS THE REMNANTS OF STORMS UP TO OUR NORTHWEST EARLY THIS MORNING ROLL SOUTHEAST THROUGH THE AREA. THERE SHOULD BE A BREAK IN THE ACTIVITY THIS AFTERNOON...BUT CAN/T RULE OUT NEW DEVELOPMENT ALONG ANY REMNANT OUTFLOW/BAROCLINIC BOUNDARIES DURING THE HEAT OF THE AFTERNOON. THE NEXT BEST CHANCE FOR STORMS WOULD BE LATER TONIGHT AS ANOTHER LARGE COMPLEX OF STORMS THAT DEVELOPS UPSTREAM EARLIER IN THE AFTERNOON ROLLS IN. && .MKX WATCHES/WARNINGS/ADVISORIES... WI...NONE. LM...NONE. && TODAY/TONIGHT AND AVIATION/MARINE...DAVIS SATURDAY THROUGH THURSDAY...ET
HAZARDOUS WEATHER OUTLOOK NATIONAL WEATHER SERVICE MILWAUKEE/SULLIVAN WI 332 AM CDT FRI JUN 21 2013 WIZ046-047-051-052-056>060-062>072-220845- MARQUETTE-GREEN LAKE-FOND DU LAC-SHEBOYGAN-SAUK-COLUMBIA-DODGE- WASHINGTON-OZAUKEE-IOWA-DANE-JEFFERSON-WAUKESHA-MILWAUKEE- LAFAYETTE-GREEN-ROCK-WALWORTH-RACINE-KENOSHA- 332 AM CDT FRI JUN 21 2013 THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF EAST CENTRAL WISCONSIN...SOUTH CENTRAL WISCONSIN AND SOUTHEAST WISCONSIN. .DAY ONE...TODAY AND TONIGHT THUNDERSTORMS ARE LIKELY. WE SHOULD SEE TWO MAIN ROUNDS OF THUNDERSTORM ACTIVITY...ONE THIS MORNING AS A COMPLEX OF STORMS TO OUR NORTHWEST DROPS SOUTHEAST INTO THE AREA. THESE SHOULD DIMINISH DURING THE AFTERNOON. THEN ANOTHER ROUND OF STORMS IS EXPECTED LATER TONIGHT AS A COMPLEX OF STORMS TO THE WEST ROLLS IN AFTER MIDNIGHT. THERE IS A SLIGHT RISK FOR SEVERE THUNDERSTORMS OVER MUCH OF THE AREA. THE MAIN THREAT WILL BE LARGE HAIL AND DAMAGING WIND. .DAYS TWO THROUGH SEVEN...SATURDAY THROUGH THURSDAY THUNDERSTORMS ARE POSSIBLE FROM TIME TO TIME DURING THIS PERIOD. THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS SATURDAY AND SUNDAY OVER MAINLY SOUTH CENTRAL WISCONSIN. THE MAIN THREAT WILL BE STRONG WINDS AND HAIL. .SPOTTER INFORMATION STATEMENT... SPOTTER ACTIVATION MAY BE NEEDED FRIDAY. LMZ643>646-220845- SHEBOYGAN TO PORT WASHINGTON WI- PORT WASHINGTON TO NORTH POINT LIGHT WI- NORTH POINT LIGHT TO WIND POINT WI- WIND POINT WI TO WINTHROP HARBOR IL- 332 AM CDT FRI JUN 21 2013 THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF LAKE MICHIGAN. .DAY ONE...TODAY AND TONIGHT THUNDERSTORMS ARE LIKELY. WE SHOULD SEE TWO MAIN ROUNDS OF THUNDERSTORM ACTIVITY...ONE THIS MORNING AS A COMPLEX OF STORMS TO OUR NORTHWEST DROPS SOUTHEAST INTO THE AREA. THESE SHOULD DIMINISH DURING THE AFTERNOON. THEN ROUND TWO IS EXPECTED LATER TONIGHT AS A COMPLEX OF STORMS TO THE WEST ROLLS IN AFTER MIDNIGHT. THERE IS A SLIGHT RISK FOR SEVERE THUNDERSTORMS OVER MUCH OF THE AREA. THE MAIN THREAT WILL BE LARGE HAIL AND DAMAGING WIND. .DAYS TWO THROUGH SEVEN...SATURDAY THROUGH THURSDAY THUNDERSTORMS ARE POSSIBLE FROM TIME TO TIME DURING THIS PERIOD. A WARM AND HUMID AIRMASS FLOWING OVER THE COLDER WATERS OF LAKE MICHIGAN WILL LIKELY RESULT IN AREAS OF FOG...POSSIBLY DENSE AT TIMES. DAVIS WWW.WEATHER.GOV/MKX
SPECIAL WEATHER STATEMENT NATIONAL WEATHER SERVICE MILWAUKEE/SULLIVAN WI 604 AM CDT FRI JUN 21 2013 WIZ046-047-056-057-062-063-211215- MARQUETTE-GREEN LAKE-SAUK-COLUMBIA-IOWA-DANE- INCLUDING THE CITIES OF...MONTELLO...BERLIN...BARABOO...PORTAGE... WISCONSIN DELLS...DODGEVILLE...MADISON 604 AM CDT FRI JUN 21 2013 ...STRONG THUNDERSTORMS APPROACHING FROM THE NORTHWEST... STRONG THUNDERSTORMS STRETCHING FROM NEAR BLACK RIVER FALLS TO LA CROSSE TO PRAIRIE DU CHIEN WILL CONTINUE TO RACE SOUTHEAST AT 45 MPH. THESE SHOULD REACH THE WISCONSIN DELLS BETWEEN 7 TO 730 THIS MORNING...AND THE MADISON AREA BETWEEN 8 AND 9 AM. AT SOME POINT...WE EXPECT THE STORMS TO BEGIN WEAKENING BEFORE PUSHING OFF TO THE EAST AND SOUTHEAST TOWARD MILWAUKEE. THESE STORMS WILL BE CAPABLE OF PRODUCING SEVERE WEATHER. THE MAIN THREAT IS STRONG AND DAMAGING WIND AND POSSIBLY LARGE HAIL. BE PREPARED FOR THE ARRIVAL OF THESE STORMS OVER THE NEXT SEVERAL HOURS. DAVIS
SPECIAL WEATHER STATEMENT NATIONAL WEATHER SERVICE MILWAUKEE/SULLIVAN WI 701 AM CDT FRI JUN 21 2013 WIZ046-056-057-211245- COLUMBIA-MARQUETTE-SAUK- 701 AM CDT FRI JUN 21 2013 ...STRONG THUNDERSTORM MOVING INTO SOUTH CENTRAL WISCONSIN... AT 700 AM CDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED STRONG THUNDERSTORMS ALONG A LINE EXTENDING FROM 31 MILES NORTH OF WISCONSIN DELLS TO 13 MILES NORTHWEST OF REEDSBURG TO 53 MILES SOUTHWEST OF REEDSBURG...MOVING EAST AT 45 MPH. ONE HALF INCH DIAMETER HAIL...WINDS UP TO 50 MPH...OCCASIONAL CLOUD TO GROUND LIGHTNING...BRIEF HEAVY DOWNPOURS...ARE POSSIBLE WITH THESE STORMS. * THUNDERSTORMS WILL BE NEAR... REEDSBURG BY 725 AM CDT... WISCONSIN DELLS AND LAKE DELTON BY 730 AM CDT... WESTFIELD BY 735 AM CDT... WISCONSIN DELLS AIRPORT BY 740 AM CDT... WEST BARABOO AND BARABOO BY 745 AM CDT... ADDITIONALLY...OTHER SCATTERED THUNDERSTORMS WERE LOCATED FROM MARQUETTE COUNTY SOUTH THROUGH THE MADISON AREA. THESE WEAKER STORMS WERE MOVING NORTHEAST. GUSTY WINDS MAY CAUSE SMALL BRANCHES TO BE BLOWN DOWN...AND LOOSE OBJECTS TO BLOW AROUND. STAY AWAY FROM HIGH OBJECTS OUTDOORS SUCH AS TREES. SEEK SHELTER IN A STURDY STRUCTURE UNTIL THESE STORMS HAVE PASSED. KAPELA
SPECIAL WEATHER STATEMENT NATIONAL WEATHER SERVICE MILWAUKEE/SULLIVAN WI 708 AM CDT FRI JUN 21 2013 WIZ056-057-062-063-067-068-211245- COLUMBIA-DANE-GREEN-IOWA-LAFAYETTE-SAUK- 708 AM CDT FRI JUN 21 2013 ...STRONG THUNDERSTORM MOVING INTO SOUTH CENTRAL WISCONSIN... AT 706 AM CDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED STRONG THUNDERSTORMS ALONG A LINE EXTENDING FROM 40 MILES NORTHWEST OF DODGEVILLE TO 70 MILES WEST OF MINERAL POINT...MOVING EAST AT 50 MPH. ONE HALF INCH DIAMETER HAIL...WINDS UP TO 50 MPH...OCCASIONAL CLOUD TO GROUND LIGHTNING...BRIEF HEAVY DOWNPOURS...ARE POSSIBLE WITH THESE STORMS. * THUNDERSTORMS WILL BE NEAR... LONE ROCK AIRPORT AND BLACKHAWK LAKE RECREATION AREA BY 745 AM CDT... GUSTY WINDS MAY CAUSE SMALL BRANCHES TO BE BLOWN DOWN...AND LOOSE OBJECTS TO BLOW AROUND. STAY AWAY FROM HIGH OBJECTS OUTDOORS SUCH AS TREES. SEEK SHELTER IN A STURDY STRUCTURE UNTIL THESE STORMS HAVE PASSED. KAPELA
SPECIAL WEATHER STATEMENT NATIONAL WEATHER SERVICE MILWAUKEE/SULLIVAN WI 745 AM CDT FRI JUN 21 2013 WIZ046-047-052-057-211345- COLUMBIA-GREEN LAKE-MARQUETTE-SHEBOYGAN- 745 AM CDT FRI JUN 21 2013 ...STRONG THUNDERSTORM MOVING THROUGH SOUTH CENTRAL WISCONSIN... AT 745 AM CDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED STRONG THUNDERSTORMS ALONG A LINE EXTENDING FROM 6 MILES NORTHWEST OF BERLIN TO 24 MILES SOUTHWEST OF BERLIN TO 39 MILES SOUTHWEST OF BERLIN...MOVING EAST AT 25 MPH. PENNY SIZE HAIL...WINDS UP TO 50 MPH...OCCASIONAL CLOUD TO GROUND LIGHTNING...ARE POSSIBLE WITH THESE STORMS. * THUNDERSTORMS WILL BE NEAR... MONTELLO BY 750 AM CDT... BERLIN BY 800 AM CDT... PRINCETON BY 805 AM CDT... GREEN LAKE BY 820 AM CDT... MARKESAN BY 840 AM CDT... GUSTY WINDS MAY CAUSE SMALL BRANCHES TO BE BLOWN DOWN...AND LOOSE OBJECTS TO BLOW AROUND. STAY AWAY FROM HIGH OBJECTS OUTDOORS SUCH AS TREES. SEEK SHELTER IN A STURDY STRUCTURE UNTIL THESE STORMS HAVE PASSED. KAPELA
The La Crosse radar (KARX), 90 km away, was scanning. The volume nearest the first event began at 12:57 UTC.
1 thunderstorm wind. Local standard time, as filed.
The Iowa County Emergency Manager reported numerous trees and power lines blown down by thunderstorm wind gusts estimated at 64 mph (56 knots).
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Wisconsin in 2013Every state in 2013This day in weather historyWarnings in Wisconsin, June 2013
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: 464523.