Strong gradient winds toppled trees and caused power outages across northwestern Wisconsin.
Every event with a place to put it; 8 filed by county or forecast zone are drawn at its center, in a lighter ring. 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 DLH wrote it up.
Strong gradient winds toppled trees and caused power outages across northwestern 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 Duluth, MN wrote its last area forecast discussion before the first event at Sep 15, 2:00 PM CST, 5 hours earlier.
AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE DULUTH MN 300 PM CDT WED SEP 15 2004 .DISCUSSION...FORECAST FOCUS WILL BE ON SEVERE THUNDERSTORM POTENTIAL AND ADDITIONAL RAIN...OVER THE NEXT 12 HOURS. UL PATTERN ACROSS NORTHERN U.S.A. FEATURES VIGOROUS NEGATIVELY TILTED TROF ACROSS HIGH PLAINS. TROF IS DEEPENING PRIMARILY DUE TO STG CAA BREAKING OUT ACRS MONTANA AND N DAKOTA. NICE THICKNESS S-PATTERN ALSO IDENTIFIES THIS. LOOKING AT CLD PATTERNS...SFC LOW CIRCULATION IS NOW OVER THE TWIN PORTS AREA AND RACING NORTH-NORTHEAST AT ROUGHLY 40 KTS. THE LOW PRESSURE CENTER...NOW AT 996MB...IS STILL TO THE SOUTH NEAR MINNEAPOLIS. THE WARM FRONT EXTENDS NORTHEAST ACRS E-CNTRL MN...OVER LAKE SUPERIOR. THE ASSCD COLD FRONT IS RAPIDLY MOVING EWD AND STRETCHES SOUTH-SOUTHWEST ACRS SOUTH-CENTRAL MN...CENTRAL IOWA...AND OVER NW MISSOURI. MODELS ARE COMING INTO BETTER AGREEMENT...WITH THE ETA TRENDING TOWARDS A 12Z GFS SOLUTION THAT INIITIALIZED WELL WITH HGHTS...WINDS...AND TEMPS AT SIG LVLS. IN ADDITION...VORT X-N DIST LINES UP WELL WITH ANALYZED JET PLACEMENT ACRS NRN ROCKIES. FOR SEVERE WEATHER...THERE IS A TORNADO WATCH IN EFFECT UNTIL 8PM THIS EVENING FOR EXTREME EASTERN NW WISCONSIN COUNTIES. POTENTIAL FOR SEVERE TSTMS AND A POSSIBLE TORNADO IS THERE WITH HELICITIES CLIMBING TO 250 AND 0-3KM SHEARS OF 40 TO 50 KTS. HOWEVER...ITS LOOKING LIKE SHEAR IS TOO STRONG FOR SIG CONV DVLPMNT THIS AFTN. THIS APPEARS TO BE THE CASE LOOKING AT METSAT ACRS AREA. TSTMS WERE DEVELOPING ALONG THE WARM-FRONT NEAR LOW CENTER AT NOONTIME...THEN DVLPMNT STARTED EAST ALNG FRNT NEAR PRICE COUNTY. VERY FEW LIGHTNING STRIKES RPTD AS MOST TSTMS ARE BEING SHEARED OFF BEFORE THEY CAN GET MUCH PAST FREEZING LVL. EXTENDED...HIGH PRESSURE WILL MOVE IN LATE TONIGHT THROUGH THE REST OF THE WEEK. BY THE WEEKEND...A DEVELOPING LOW PRESSURE SYSTEM IS EXPECTED TO BRING STRONG WAA FOR TEMPS RETURNING TO ABOVE NORMAL THROUGH THE BEGINNING OF NEXT WEEK. LATEST FORECASTS BRING DO NOT BRING ASSCD TROF ACRS UNTIL MIDDLE OF NEXT WEEK...SO WILL KEEP WITH PREVIOUS FCST THANKS FOR COORDINATION MPX. .DLH...WATCHES/WARNINGS/ADVISORIES MN...NONE. WI...NONE. MELDE
HAZARDOUS WEATHER OUTLOOK NATIONAL WEATHER SERVICE DULUTH MN 730 AM CDT WED SEP 15 2004 MNZ010>012-018>021-025-026-033>038-WIZ001>004-006>009-161230- ASHLAND-BAYFIELD-BURNETT-C. ST. LOUIS-CROW WING-DOUGLAS-IRON- KOOCHICHING-N. AITKIN-N. CASS-N. ITASCA-N. LAKE/N. COOK-N. ST. LOUIS- PINE-PRICE-S. AITKIN-S. CASS-S. COOK/LAKESHORE-S. ITASCA- S. LAKE/LAKESHORE-S. ST. LOUIS/CARLTON-SAWYER-WASHBURN- 730 AM CDT WED SEP 15 2004 THIS HAZARDOUS WEATHER OUTLOOK IS FOR NORTHEASTERN MINNESOTA AND NORTHWESTERN WISCONSIN. .DAY ONE...TODAY AND TONIGHT A STRONG LOW PRESSURE SYSTEM WILL MOVE THROUGH THE FORECAST AREA TODAY. SHOWERS AND A FEW THUNDERSTORMS ARE EXPECTED THROUGHOUT NORTHEAST MINNESOTA AND NORTHWEST WISCONSIN. SOME STORMS MAY BECOME SEVERE OVER COOK COUNTY IN MINNESOTA AND ALL OF NORTHWEST WISCONSIN THIS AFTERNOON. HAIL AND STRONG WINDS ARE THE PRIMARY SEVERE THREAT. ALSO HEAVY RAINS ARE EXPECTED WITH THIS SYSTEM...WITH UP TO 2 INCHES OF RAIN POSSIBLE. LOOK FOR LOCALIZED PONDING OF WATER IN FAVORED AREAS. GALE WARNINGS ARE IN EFFECT FOR WESTERN LAKE SUPERIOR THROUGH THIS EVENING. .DAYS TWO THROUGH SEVEN...THURSDAY THROUGH TUESDAY THUNDERSTORMS ARE POSSIBLE MONDAY NIGHT INTO TUESDAY. .SPOTTER INFORMATION STATEMENT... SKYWARN SPOTTER ACTIVATION MAY BE NEEDED THIS AFTERNOON INTO THIS EVENING. && MORE INFORMATION MAY BE OBTAINED AT THE FOLLOWING URL: HTTP://WWW.CRH.NOAA.GOV/DLH KFM
SPECIAL WEATHER STATEMENT NATIONAL WEATHER SERVICE DULUTH MN 336 PM CDT WED SEP 15 2004 MNZ037-038-WIZ001>003-006>008-152100- ASHLAND-BAYFIELD-BURNETT-DOUGLAS-PINE-S. ST. LOUIS/CARLTON-SAWYER- WASHBURN- 336 PM CDT WED SEP 15 2004 ...TORNADO WATCH NUMBER 824 HAS BEEN CANCELLED FOR NORTHEASTERN MINNESOTA AND MUCH OF NORTHWESTERN WISCONSIN... THE TORNADO WATCH THAT WAS IN EFFECT FOR THE COUNTIES OF...CARLTON AND PINE IN MINNESOTA...AND DOUGLAS...BURNETT...WASHBURN...SAWYER... BAYFIELD...AND ASHLAND IN WISCONSIN...HAS BEEN CANCELLED. THE STORMS HAVE MOVED EAST AND NORTH OF THE AREA. SHIMON
The national radar mosaic for the moment the first event began.
8 strong wind. Local standard time, as filed.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Wisconsin in 2004Every state in 2004This day in weather historyWarnings in Wisconsin, September 2004
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: 5423405, 5423406, 5423407, 5423408, 5423981, 5423982, 5423983, 5423984.