A warm front remained nearly stationary across central Iowa and northern Illinois during the evening hours of September 15th. A complex of thunderstorms developed north of the warm front and tracked across portions of southeast Minnesota.
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 ARX wrote it up.
A warm front remained nearly stationary across central Iowa and northern Illinois during the evening hours of September 15th. A complex of thunderstorms developed north of the warm front and tracked across portions of southeast Minnesota. The thunderstorms knocked down trees, produced a sixty-one mile per hour wind gust at the Austin Municipal airport (Mower County) and golf ball size hail near Nodine (Winona County).
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 La Crosse, WI wrote its last area forecast discussion before the first event at Sep 15, 2:47 PM CST, 3 hours 57 minutes earlier.
AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE LA CROSSE WI 347 PM CDT WED SEP 15 2010 .SHORT TERM...TONIGHT THROUGH FRIDAY NIGHT MUCH OF THE ATTENTION FOR TODAY HAS BEEN WATCHING THE DEEPENING SHORT WAVE MOVING OUT OF EASTERN SOUTH DAKOTA. THERE APPEARS TO BE TWO WARM FRONTS AHEAD OF THIS WAVE. THE FIRST IS LOCATED NEAR THE INTERSTATE 80 CORRIDOR. THE SECOND ONE EXTENDS FROM JUST NORTH OF SIOUX FALL SOUTH DAKOTA EAST TO ALBERT LEA MINNESOTA TO MILWAUKEE WISCONSIN. MEANWHILE A COLD FRONT EXTENDED FROM CARPENTER SOUTH DAKOTA SOUTHWARD TO YANKTON SOUTH DAKOTA AND SOUTHWEST TO CHAMBERS NEBRASKA. MUCH OF THE PRECIPITATION IS CURRENTLY LOCATED ALONG THE COLD FRONT AND A 900 T0 700 MB FRONTOGENTIC ZONE ACROSS CENTRAL MINNESOTA AND NORTHERN WISCONSIN. MEANWHILE IN THE WARM SECTOR SOME SUNSHINE HAS BROKEN OUT AND THIS HAS ALLOWED TEMPERATURES TO WARM INTO THE UPPER 70S AND LOWER 80S. THE 15.12Z AND 15.18Z MODELS ARE STRUGGLING WITH HOW MUCH MOISTURE WILL BE BROUGHT NORTHWARD AHEAD OF THIS FRONT AS A RESULT THERE IS A FEELING THAT THE MIXED LAYER CAPES ARE A BIT TOO HIGH AND THEY SHOULD BE IN THE 1000 TO 1500 J/KG RANGE INSTEAD OF 2000 TO 2500 J/KG...AND THIS COULD BECOME A FACTOR AS WE LOSE DIURNAL HEATING THIS EVENING. WHILE THE INSTABILITY IS IN QUESTION...THE SHEAR IS NOT...AND IT IS MORE THAN SUFFICIENT FOR THE DEVELOPMENT OF SUPER CELLS AS LONG AS THERE IS ENOUGH INSTABILITY BY THE TIME THE THUNDERSTORMS GET INTO OUR AREA WHICH SHOULD BE AFTER 15.23Z. WE WILL INITIALLY HAVE TO WATCH THE WARM FRONT FOR THE POSSIBILITY OF LARGE HAIL AND AN ISOLATED TORNADO IN SOUTHEAST MINNESOTA. IF THIS OCCURRED...IT LOOKS LIKE THE THREAT WOULD BE LIMITED TO BETWEEN 15.23Z AND 16.01Z. HOWEVER THE GREATER CONCERN /ALBEIT STILL SMALL/ LOOKS TO BE ASSOCIATED WITH THE COLD FRONT AND THE QLCS THAT WILL BE LOCATED ALONG IT. THIS LINE OF THUNDERSTORMS MAY PRODUCE SOME WIND DAMAGE BETWEEN 16.01Z AND 16.04Z. ON FRIDAY AND FRIDAY NIGHT...THE MODELS CONTINUE TO BRING ANOTHER COLD FRONT SOUTHWARD INTO THE AREA. BOTH THE 925 AND 850 MB MOISTURE TRANSPORT ALONG AND AHEAD OF THIS FRONT IS NOT OVERLY THAT IMPRESSIVE. IN ADDITION...THE INSTABILITY IS NOT THAT GREAT. THE 0-3 KM MIXED LAYER CAPES IS GENERALLY LESS THAN 300 J/KG AND THE 0-3 KM MOST UNSTABLE CAPES ARE RUNNING LESS THAN 600 J/JG. AS A RESULT...THE PRECIPITATION PROBABILITIES WERE LEFT IN THE 20 TO 30 PERCENT RANGE DESPITE CONSISTENT SIGNAL FOR LIGHT PRECIPITATION IN THE MODELS. .LONG TERM...SATURDAY THROUGH WEDNESDAY THE 15.00Z AND 15.12Z MODELS ARE CONTINUING TO STRUGGLE WITH THE POSITION OF A FRONTAL BOUNDARY DURING THIS TIME PERIOD...AND THIS WILL LIKELY CONTINUE AS THE STRONG TROPICAL FORCING THAT HAS RESIDED ACROSS INDONESIA FOR MUCH OF SEPTEMBER SHIFTS EASTWARD INTO THE INDIAN OCEAN. AS A RESULT...MUCH UNCERTAINTY REMAINS WITH THIS ENTIRE TIME PERIOD. IN THE 15.12Z MODELS...THE COLD FRONT THAT MOVES THROUGH THE REGION ON FRIDAY AND FRIDAY NIGHT BECOMES STATIONARY ACROSS CENTRAL IOWA ON SATURDAY. THIS FRONT WILL CONTINUE TO BE THE FOCUS FOR SHOWERS AND POSSIBLY SOME THUNDERSTORMS MAINLY SOUTH OF INTERSTATE 90 FOR SATURDAY THROUGH SUNDAY. ON SUNDAY NIGHT AND MONDAY MORNING...THE ECMWF CONTINUES TO SUGGEST THAT A WARM FRONT WILL MOVE NORTHWARD ACROSS THE AREA. MEANWHILE THE GFS CONTINUES TO SHOW THAT THIS FRONT WILL NOT MOVE THROUGH THE AREA UNTIL MONDAY AFTERNOON AND EVENING. THIS FRONT WILL HAVE TO BE WATCHED CAREFULLY...BECAUSE THERE WILL BE ELEVATED CAPES AND SHEAR FOR THE POTENTIAL DEVELOPMENT OF SUPER CELLS. IF THIS DOES OCCUR...THERE WILL BE THE POTENTIAL OF LARGE HAIL. BESIDES THIS...THE FRONT WILL CREATE THE POTENTIAL OF A MAJOR BUST POTENTIAL WITH OUR MAXIMUM TEMPERATURES ON MONDAY. IF WE ARE ABLE TO GET INTO THE WARM SECTOR...TEMPERATURES WOULD LIKELY CLIMB INTO THE UPPER 70S AND LOWER 80S. MEANWHILE IF WE STAY IN THE CLOUDS AND PRECIPITATION...TEMPERATURES WOULD REMAIN IN THE 50S AND 60S. ON TUESDAY AFTERNOON AND EVENING...THERE LOOKS TO BE THE POTENTIAL OF ADDITIONAL SEVERE WEATHER AS A COLD FRONT MOVES THROUGH THE REGION. HOW GREAT WILL THIS POTENTIAL WILL DEPEND GREATLY ON CLEAN THE WARM SECTOR REMAINS. && .AVIATION...THROUGH THURSDAY MAIN AVIATION FORECAST CONCERNS ARE TIMING OF NEXT ROUND OF SHOWERS AND THUNDERSTORMS INTO BOTH KLSE AND KRST TAF SITES LATE THIS AFTERNOON AND EVENING. FIRST SHORTWAVE TROUGH EXITED THE TAF SITES LATE THIS MORNING. NEXT VIGOROUS SHORTWAVE TROUGH OVER EASTERN SOUTH DAKOTA MOVES EAST INTO EASTERN MINNESOTA AND WESTERN WISCONSIN THIS EVENING. STRONG VERTICAL MOTION AND FORCING ASSOCIATED WITH SHORTWAVE TROUGH WILL ALLOW FOR SHOWERS AND THUNDERSTORMS TO RE- DEVELOP OVER PORTIONS OF WESTERN MINNESOTA LATE THIS AFTERNOON AND MOVE EAST INTO THE AREA EARLY THIS EVENING. THE LATEST 15.12Z LOCAL HIGH RESOLUTION MODELS SUGGEST CONVECTION ASSOCIATED WITH SHORTWAVE TROUGH...WILL MOVE INTO SOUTHEAST MINNESOTA AROUND OR AFTER 00Z THURSDAY. AT THIS TIME...HAVE KEPT PREVIOUS TIMING OF CONVECTION IN THE KRST TAF AT 22Z AND 00Z AT KLSE TAF. LATEST 15.12Z NAM AND GFS INDICATE SHOWERS AND POSSIBLY ISOLATED THUNDERSTORMS TO WRAP AROUND DEEPENING SURFACE LOW PRESSURE OVER WESTERN WISCONSIN TONIGHT. WITH BOTH MODELS INDICATING LOW LEVEL MOISTURE AT 925MB WRAPPING AROUND LOW PRESSURE AFTER 06Z THURSDAY...HAVE KEPT TREND OF LIFR/IFR CEILING CONDITIONS AT BOTH KRST AND KLSE AFTER 06Z THURSDAY. IN ADDITION...PRESSURE GRADIENT TIGHTENS ON BACKSIDE OF LOW PRESSURE AFTER 06Z THURSDAY ACROSS SOUTHEAST MINNESOTA. WINDS WILL INCREASE OUT OF THE NORTHWEST AFTER 06Z THURSDAY AND BE SUSTAINED AT 15 TO 20 KNOTS WITH GUSTS UP TO 25 KNOTS AT KRST THROUGH THURSDAY MORNING. && .ARX WATCHES/WARNINGS/ADVISORIES... WI...NONE. MN...NONE. IA...NONE. && SHORT/LONG TERM...BOYNE AVIATION...DTJ
HAZARDOUS WEATHER OUTLOOK NATIONAL WEATHER SERVICE LA CROSSE WI 130 PM CDT WED SEP 15 2010 IAZ008>011-018-019-029-030-MNZ079-086>088-094>096-WIZ017-029- 032>034-041>044-053>055-061-161100- ADAMS-ALLAMAKEE-BUFFALO-CHICKASAW-CLARK-CLAYTON-CRAWFORD-DODGE- FAYETTE-FILLMORE-FLOYD-GRANT-HOUSTON-HOWARD-JACKSON-JUNEAU- LA CROSSE-MITCHELL-MONROE-MOWER-OLMSTED-RICHLAND-TAYLOR-TREMPEALEAU- VERNON-WABASHA-WINNESHIEK-WINONA- 130 PM CDT WED SEP 15 2010 THIS HAZARDOUS WEATHER OUTLOOK IS FOR PARTS OF SOUTHEAST MINNESOTA...NORTHEAST IOWA AND SOUTHWEST AND CENTRAL WISCONSIN. .DAY ONE...THIS AFTERNOON AND TONIGHT ANOTHER ROUND OF THUNDERSTORMS WILL OVERSPREAD THE REGION LATE THIS AFTERNOON AND INTO TONIGHT. A FEW OF THESE THUNDERSTORMS MAY BECOME SEVERE BETWEEN 6 PM AND MIDNIGHT...MAINLY SOUTH OF INTERSTATE 94. THE MAIN THREATS WILL BE LARGE HAIL AND DAMAGING WINDS. .DAYS TWO THROUGH SEVEN...THURSDAY THROUGH TUESDAY THUNDERSTORMS ARE POSSIBLE ACROSS NORTHEAST IOWA AND FAR SOUTHWEST WISCONSIN SATURDAY AND SATURDAY NIGHT AND THEN ACROSS MUCH OR ALL OF THE AREA SUNDAY THROUGH TUESDAY. SEVERE WEATHER APPEARS UNLIKELY WITH ANY STORMS SATURDAY AND SATURDAY NIGHT. IT IS STILL TO EARLY TO DETERMINE THE CHANCES OF SEVERE WEATHER WITH ANY OF THE POTENTIAL STORMS FROM SUNDAY THROUGH TUESDAY. .SPOTTER INFORMATION STATEMENT... SPOTTER ACTIVATION MAY BE NEEDED THIS EVENING. .EMERGENCY MANAGEMENT COORDINATION... NO CALL IS SCHEDULED. DTJ
SPECIAL WEATHER STATEMENT NATIONAL WEATHER SERVICE LA CROSSE WI 606 PM CDT WED SEP 15 2010 MNZ086-087-094-160000- DODGE-MOWER-OLMSTED- 606 PM CDT WED SEP 15 2010 ...STRONG TO SEVERE THUNDERSTORMS APPROACHING DODGE...MOWER AND OLMSTED COUNTIES... AT 602 PM...DOPPLER RADAR INDICATED A STRONG TO SEVERE THUNDERSTORM 27 MILES WEST OF BLOOMING PRAIRIE...MOVING EAST AT 25 MPH. LARGE HAIL...HEAVY RAIN AND FREQUENT DANGEROUS LIGHTNING MAY ACCOMPANY THIS THUNDERSTORM. SEVERE WEATHER HAS BEEN REPORTED WITH THIS STORM. WARNINGS MAY BE NEEDED AS THIS STORM GETS CLOSER WITHIN THE NEXT ONE TO TWO HOURS. LOCATIONS THAT MAY BE AFFECTED INCLUDE... CLAREMONT...DODGE CENTER...KASSON...BYRON...AND ROCHESTER. LIGHTNING CAN BE A KILLER AND MAY STRIKE MILES AWAY FROM THE STORM. MOVE INDOORS OR FIND A VEHICLE TO SHELTER IN. BE ALERT FOR STORMS THAT MAY PRODUCE LARGE HAIL. MOVE INDOORS AND AWAY FROM WINDOWS IF A WARNING IS ISSUED. HALBACH
SPECIAL WEATHER STATEMENT NATIONAL WEATHER SERVICE LA CROSSE WI 702 PM CDT WED SEP 15 2010 IAZ008-009-018-019-MNZ086-087-094-095-160100- CHICKASAW-DODGE-FILLMORE-FLOYD-HOWARD-MITCHELL-MOWER-OLMSTED- 702 PM CDT WED SEP 15 2010 ...STRONG THUNDERSTORMS EXPECTED IN CHICKASAW...DODGE...FILLMORE... FLOYD...HOWARD...MITCHELL...MOWER AND OLMSTED COUNTIES... AT 655 PM...DOPPLER RADAR INDICATED STRONG THUNDERSTORMS FROM OWATONNA TO MASON CITY...MOVING NORTHEAST AT 45 MPH. WIND GUSTS UP TO 55 MPH AND SMALL HAIL MAY ACCOMPANY THESE STRONG THUNDERSTORMS. A GUST OF 48 MPH OCCURRED AT THE MASON CITY AIRPORT AT 649 PM WITH THE STORMS. LOCATIONS THAT MAY BE AFFECTED INCLUDE... ROCKFORD...NORA SPRINGS...AUSTIN...ROCHESTER...SPRING VALLEY...ST. ANSGAR...OSAGE AND FLOYD. IF THE STORMS INTENSIFY A LITTLE MORE...THEY COULD BECOME SEVERE. IF A WARNING IS ISSUED...MOVE INDOORS AND TAKE ANY OTHER ACTIONS TO PROTECT LIFE AND PROPERTY. AJ
The Minneapolis radar (KMPX), 134 km away, was scanning. The volume nearest the first event began at 00:44 UTC.
6 thunderstorm wind, 5 hail, 2 flood. Local standard time, as filed.
Six trees were blown down and a camper was blown over.
A fence was blown onto an automobile and a large tree was blown into power lines.
The automated weather observing equipment at the Austin airport measured a sixty-one mile per hour wind gust.
Several trees were blown down in the township of Hart.
Squad cars were pulled from flooded streets by tow trucks.
A street light pole and stop lights were blown down in the city of Winona.
Small trees were knocked down along County Road 7.
Water was over roads near the intersection of County Roads 125 and 5.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Minnesota in 2010Every state in 2010This day in weather historyWarnings in Minnesota, September 2010
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: 257598, 257596, 257612, 257613, 257614, 257616, 257600, 257602, 260719, 257622, 257617, 257633, 260718.