During the morning of Saturday, September 20th, a complex of thunderstorms developed across eastern North Dakota, and moved southeast across west central Minnesota by the afternoon, and through most of southern Minnesota by the early evening. Embedded thunderstorms formed lines and caused severe wind gusts from west central, southeast to 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 MPX wrote it up.
During the morning of Saturday, September 20th, a complex of thunderstorms developed across eastern North Dakota, and moved southeast across west central Minnesota by the afternoon, and through most of southern Minnesota by the early evening. Embedded thunderstorms formed lines and caused severe wind gusts from west central, southeast to southeast Minnesota. Most of the gusts were between 40 and 55 mph, but a few gusted over 60 mph and caused wind damage. In addition, hail formed near Waseca, and dropped a considerable amount in a short period of time.
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 Twin Cities, MN wrote its last area forecast discussion before the first event at Sep 20, 1:55 PM CST, 25 minutes earlier.
AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE TWIN CITIES/CHANHASSEN MN 255 PM CDT SAT SEP 20 2014 .SHORT TERM...(THIS EVENING THROUGH SUNDAY) ISSUED AT 255 PM CDT SAT SEP 20 2014 SHORT TERM CONCERNS DEAL SQUARELY WITH THE SEVERE WEATHER THREAT THROUGH EARLY THIS EVENING. A BROKEN LINE OF STORMS FORMED OVER NODAK EARLIER TODAY AND HAS ORGANIZED SOMEWHAT AS IT PUSHED INTO NORTHWEST WISCONSIN EARLY THIS AFTERNOON. NOT TOO MUCH SEVERE WEATHER BEING REPORTED ATTM...MAINLY DUE TO THE OVERALL LACK OF DESTABILIZATION. MLCAPE VALUES OF LESS THAN 500 J/KG ARE EXPECTED TO CONTINUE THROUGHOUT THE EVENT. HOWEVER...STRONG FORCING WITH THE MID LEVEL TROUGH AND VERY STRONG WINDS IN THE MID AND UPPER LEVELS /60+ KT AT 500 MB AND 130+ KT AT 300 MB/...ACCOMPANIED BY INVERTED V SOUNDINGS WILL BRING GOOD DOWNWARD MOMENTUM AND THUS A THREAT FOR MAINLY DAMAGING WINDS. LACK OF INSTABILITY AND LOW TOPPED CONVECTION WILL LIMIT ANY HAIL POSSIBILITY. THE LINE IS MOVING EAST/SOUTHEAST AROUND 45 KT WHICH SHOULD REACH STC AROUND 5 PM AND MSP METRO BETWEEN 6 PM AND 7 PM. VERY HIGH TEMPORAL GRID RESOLUTION AND CATEGORICAL POPS WERE INCLUDED WITH RELATIVELY HIGH CONFIDENCE DUE TO VERY GOOD AGREEMENT AMONGST THE CONVECTIVE ALLOWING MODELS. A GENERAL WEAKENING CAN BE EXPECTED AFTER SUNSET AS THE LINE ENTERS WISCONSIN WHEN INSTABILITY BECOMES NIL. WRAP AROUND SHOWERS MAY DROP SOUTH INTO ERN MN AND WRN WI LATE THIS EVENING AND OVERNIGHT AS THE UPPER LOW PUSHES EAST. THESE SHOWERS MAY LINGER INTO EARLY SUNDAY WITH THE CYCLONIC FLOW CONTINUING...BUT SURFACE RIDGING SHOULD PROVIDE ENOUGH SUBSIDENCE BY AFTERNOON TO LOWER THE THREAT WITH TIME. .LONG TERM...(SUNDAY NIGHT THROUGH SATURDAY) ISSUED AT 255 PM CDT SAT SEP 20 2014 NOT MUCH GOING ON IN THE LONG TERM IN TERMS OF SENSIBLE WEATHER... BUT A MAJOR PATTERN SHIFT IS STILL ON TAP THAT WILL BRING MUCH ABOVE NORMAL TEMPERATURES BY LATE NEXT WEEK. AS THE DIGGING TROUGH FROM TONIGHT KICKS EAST...MID LEVEL RIDGING WILL BUILD INTO THE GREAT LAKES AND UPPER MIDWEST EARLY NEXT WEEK. THE MID LEVEL RIDGE WILL BE CENTERED OVER THE SOUTHERN ROCKIES AND WILL ALLOW THE CUT OFF LOW OVER CALIFORNIA TO BE KICKED NORTHEAST INTO THE UPPER MIDWEST BY MIDWEEK. NOT EXPECTING MUCH TO BE ACCOMPANIED WITH THIS SYSTEM ASIDE FROM A LOW CHANCE OF SHOWERS AND THUNDERSTORMS AND COOLER TEMPERATURES. THE THUNDER THREAT MAY BE OVERPLAYED A BIT CONSIDERING POOR LAPSE RATES...WEAK FORCING...AND DRY BOUNDARY LAYER AIR. DID NOT MAKE TOO MANY CHANGES TO THE PREVIOUS FORECAST. MODELS DIVERGE A BIT BEYOND MIDWEEK WITH THE CANADIAN AND GFS BUILDING THE RIDGE NORTH ACROSS THE ROCKIES WHILE A PIECE OF ENERGY ROUNDING THIS RIDGE IS DETACHED FROM AN ACCELERATING TROUGH OVER NORTHERN CANADA. THIS WAVE THEN MAKES AN ODD DIVE SOUTH OR SOUTHWEST ACROSS THE PLAINS INTO A WEAKNESS IN THE RIDGE. THE ECMWF SEEMS TO KEEP THE FEATURE ASSOCIATED WITH THE STRONGER WESTERLIES ACROSS CANADA WHICH MAKES MOST SENSE. OTHERWISE...A MASSIVE RIDGE IS EXPECTED TO ENCOMPASS ALL OF THE CENTRAL AND EASTERN U.S. TO ROUND OFF THE END OF THE MONTH. SEVERAL MEMBERS OF THE GFS ENSEMBLE...AS WELL AS THE OPERATIONAL ECMWF...CENTER AN ANOMALOUS 591+ DM RIDGE OVER THE GREAT LAKES FRIDAY AND SATURDAY. A SET UP LIKE THIS WOULD NORMALLY BRING THE UPPER MIDWEST A HEAT WAVE...BUT IT IS RATHER DIFFICULT TO GET OPPRESSIVE HEAT IN LATE SEPTEMBER. TEMPS WILL STILL RUN 10-20 DEGREES ABOVE AVERAGE AND A FEW DAYS WITH HIGHS IN THE 80S APPEAR LIKELY IF THE CENTER OF THE RIDGE DOES BUILD CLOSE BY. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON) ISSUED AT 1157 AM CDT SAT SEP 20 2014 MAIN AVIATION CONCERN WILL BE LINE OF SHRA/TSRA EXPECTED TO DROP SOUTHEAST THROUGH THE AREA FROM LATER THIS AFTERNOON INTO EARLY EVENING. STORMS WILL BE MOVING VERY QUICKLY... AROUND 45 KT OR SO... AND COULD PRODUCE SOME LOCALLY SEVERE WIND GUSTS THAT WILL NEED TO BE MONITORED FOR TAF AMENDMENTS. KMSP...OVERALL CONFIDENCE IS FAIRLY HIGH... ALTHOUGH CEILING AND VISIBILITIES COULD CERTAINLY WIND UP LOWER THAN FORECAST DURING ANY SHRA/TSRA. SOME UNCERTAINTY EXISTS WITH CHANCES FOR MVFR CEILINGS LATER TONIGHT... SO THAT WILL NEED TO BE MONITORED. /OUTLOOK FOR KMSP/ MON...VFR. WINDS W 5-10 KTS. TUE...VFR. WINDS SE 5-10 KTS. WED...VFR... MVFR POSSIBLE WITH A CHANCE OF SHRA/TSRA. WINDS S 10-15 KTS. && .MPX WATCHES/WARNINGS/ADVISORIES... MN...NONE. WI...NONE. && SHORT TERM...BORGHOFF LONG TERM...BORGHOFF AVIATION...
HAZARDOUS WEATHER OUTLOOK...UPDATED NATIONAL WEATHER SERVICE TWIN CITIES/CHANHASSEN MN 1207 PM CDT SAT SEP 20 2014 MNZ041>045-047>070-073>078-082>085-091>093-WIZ014>016-023>028- 211715- DOUGLAS-TODD-MORRISON-MILLE LACS-KANABEC-STEVENS-POPE-STEARNS- BENTON-SHERBURNE-ISANTI-CHISAGO-LAC QUI PARLE-SWIFT-CHIPPEWA- KANDIYOHI-MEEKER-WRIGHT-HENNEPIN-ANOKA-RAMSEY-WASHINGTON- YELLOW MEDICINE-RENVILLE-MCLEOD-SIBLEY-CARVER-SCOTT-DAKOTA- REDWOOD-BROWN-NICOLLET-LE SUEUR-RICE-GOODHUE-WATONWAN-BLUE EARTH- WASECA-STEELE-MARTIN-FARIBAULT-FREEBORN-POLK-BARRON-RUSK- ST. CROIX-PIERCE-DUNN-PEPIN-EAU CLAIRE- 1207 PM CDT SAT SEP 20 2014 THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF CENTRAL AND SOUTHERN MINNESOTA... AND WEST CENTRAL WISCONSIN. .DAY ONE...THIS AFTERNOON AND TONIGHT A LINE OF STRONG TO SEVERE THUNDERSTORMS WILL RACE SOUTHEAST ACROSS CENTRAL AND SOUTHERN MINNESOTA LATER THIS AFTERNOON AND INTO WESTERN WISCONSIN EARLY THIS EVENING. THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS THE AREA. THE LARGEST THREAT WILL BE DAMAGING WIND...WITH A SECONDARY THREAT FOR LARGE HAIL. .DAYS TWO THROUGH SEVEN...SUNDAY THROUGH FRIDAY THUNDERSTORMS ARE POSSIBLE TUESDAY NIGHT INTO WEDNESDAY NIGHT. THIS ACTIVITY IS NOT EXPECTED TO BE SEVERE. .SPOTTER INFORMATION STATEMENT... SKYWARN SPOTTER ACTIVATION WILL LIKELY BE NEEDED BETWEEN 4 PM AND 8 PM. BORGHOFF
SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE TWIN CITIES/CHANHASSEN MN
214 PM CDT SAT SEP 20 2014
MNZ041-047-048-202015-
DOUGLAS-POPE-STEVENS-
214 PM CDT SAT SEP 20 2014
...THUNDERSTORMS MOVING INTO DOUGLAS...NORTHWEST POPE AND NORTHERN
STEVENS COUNTIES THROUGH 315 PM CDT...
AT 211 PM CDT...WEATHER SERVICE RADAR WAS TRACKING STRONG
THUNDERSTORMS ALONG A LINE EXTENDING FROM 13 MILES NORTH OF FERGUS
FALLS TO 6 MILES SOUTHEAST OF CHARLESVILLE TO 16 MILES SOUTHWEST OF
WHEATON. THESE STORMS WERE MOVING EAST AT 45 MPH.
WINDS UP TO 50 MPH ARE EXPECTED WITH THESE STORMS.
* LOCATIONS IN OR NEAR THE PATH OF THESE STORMS INCLUDE...
MELBY.
FISH LAKE.
MILLERVILLE.
HOLMES CITY.
LEAF VALLEY.
MORRIS AIRPORT.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
A SEVERE THUNDERSTORM WATCH REMAINS IN EFFECT FOR THE AREA.
&&
LAT...LON 4576 9625 4577 9577 4608 9579 4612 9576
4611 9514 4570 9514 4550 9576 4556 9625
4571 9627
TIME...MOT...LOC 1914Z 281DEG 38KT 4647 9607 4589 9612
4568 9673SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE TWIN CITIES/CHANHASSEN MN
319 PM CDT SAT SEP 20 2014
MNZ041>043-202115-
DOUGLAS-MORRISON-TODD-
319 PM CDT SAT SEP 20 2014
...STRONG LINE OF THUNDERSTORMS MOVING INTO EASTERN DOUGLAS...WESTERN
MORRISON AND TODD COUNTIES THROUGH 415 PM CDT...
AT 317 PM CDT...WEATHER SERVICE RADAR WAS TRACKING STRONG
THUNDERSTORMS ALONG A LINE EXTENDING FROM 9 MILES NORTH OF WADENA TO
9 MILES SOUTHEAST OF PARKERS PRAIRIE TO 7 MILES SOUTHEAST OF
ALEXANDRIA. THESE STORMS WERE MOVING EAST AT 45 MPH.
WINDS UP TO 50 MPH ARE EXPECTED WITH THESE STORMS.
* LOCATIONS IN OR NEAR THE PATH OF THESE STORMS INCLUDE...
HEWITT.
LAKE OSAKIS.
WEST UNION.
LITTLE SAUK.
PHILBROOK.
MOTLEY.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
A SEVERE THUNDERSTORM WATCH REMAINS IN EFFECT FOR THE AREA.
&&
LAT...LON 4631 9455 4634 9443 4629 9433 4623 9438
4617 9436 4616 9418 4582 9426 4582 9435
4578 9428 4577 9428 4576 9542 4612 9528
4612 9515 4637 9515 4638 9475
TIME...MOT...LOC 2019Z 289DEG 40KT 4655 9504 4608 9514
4580 9525The Minneapolis radar (KMPX), 167 km away, was scanning. The volume nearest the first event began at 20:19 UTC.
15 thunderstorm wind, 4 hail. Local standard time, as filed.
A 10 inch wide apple tree was uprooted. There were also several other reporting sites that had wind gusts over 50 mph.
A few trees were blown down near Diamond Lake.
A large pear tree was uprooted.
A storm chaser measured a wind gust of 60 mph on his car anemometer west of Hutchinson.
Several large trees were snapped off or uprooted throughout the city of Hutchinson. There was also a measured wind gust of 54 mph at the Hutchinson Airport.
Numerous large tree limbs were blown off near Waverly.
A large tree branch was blown off in the town of Biscay.
Large trees were blown down across Highway 21 north of New Ulm.
Several large trees were blown down in the city of New Ulm.
A measured wind gust of 51 knots was reported south of Victoria. In addition, numerous large tree branches were blown down.
A roof was blown off and power lines were down in the town of Cambria.
Power lines were blown down in Lake Crystal.
Nearly 100 trees were blown down in the city of Waseca. It was also accompanied by large hail. In addition, an outdoor tent was blown down trapping approximately 30-40 people underneath the tent.
Hail was piled up in town, with some areas up to 6 inches deep in the town of Waseca.
Numerous trees and large branches were blown down in the town of Madelia.
Numerous trees were blown down around the city of Mankato. There was also a measured wind gust of 51 mph at the Mankato Airport.
There was a large swath of hail, mainly penny size or smaller, that moved from east of Waseca along the Steele, Waseca County line, southeast to near Blooming Prairie. There was damage to corn crops associated with the hail.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Minnesota in 2014Every state in 2014This day in weather historyWarnings in Minnesota, September 2014
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: 535696, 535848, 535698, 535701, 535699, 535704, 535705, 535706, 535707, 536137, 535711, 535715, 535716, 538383, 535717, 535721, 535722, 535835, 538387.