Strong winds, associated with an intense low pressure system, downed trees and power lines across parts of north-central and east-central Wisconsin. ).
Every event with a place to put it; 3 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 GRB wrote it up.
Strong winds, associated with an intense low pressure system, downed trees and power lines across parts of north-central and east-central Wisconsin. One of the downed trees landed on a vehicle in Appleton (Outagamie co.).
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 Sep 15, 2:45 PM CST, 5 minutes earlier.
AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE GREEN BAY WI 345 PM CDT WED SEP 15 2004 .SHORT RANGE...STRONG UPPER TROUGH LIFTING ACROSS THE AREA HELPING TO PRODUCE STRONG TO SEVERE THUNDERSTORMS DURING THE LATE AFTERNOON AND EARLY EVENING. ACTIVITY SHOULD COME TO AN END BY AROUND MIDNIGHT AS DRIER AIR BEHIND SURFACE FRONT MOVES THROUGH. STRONG GRADIENT WINDS THIS EVENING SHOULD RELAX AS STRONG SURFACE LOW MOVES FARTHER AWAY. THURSDAY SHOULD BE DRY AND A BIT COOLER WITH A WEST WIND. .LONG RANGE...THU NGT INTO NXT WED. MAIN FCST CONCERN THRU NXT MON WL MAINLY BE ON TEMPS WITH PCPN CHCS TAKING OVR FOR NXT TUE AND WED. STARTING THU NGT...AS SFC HI PRES PUSHES TOWARD THE ERN GREAT LKS...SFC WNDS TO BACK SW BRINGING AT LEAST SOME MID CLDS BACK ESP TO WRN SECTIONS OF THE FCST AREA. THERE IS ALSO A WEAK SHRTWV TROF PROGGED TO APPROACH FROM THE UPR MIDWEST. CURRENT THINKING IS THAT BEST FORCING TO REMAIN TO OUR WEST THU NGT...BUT THEN MOV ACROSS NRN WI ON FRI. WL DROP SPRINKLES FOR THU NGT AND ADD A SLGT CHC OF SHWRS OVR NRN WI FOR FRI. WEAK INSTABILITY SHOULD KEEP THUNDER OUT OF THE FCST. WHATEVER FORCING IS LEFT DEPARTS THE RGN FRI NGT ALLOWING ANOTHER HI PRES OVR SRN ONTARIO TO TAKE OVR OUR WEATHER. WL KEEP FCST DRY. HEADED INTO THE EXTENDED...THE MEAN FLOW TO BE DOMINATED BY BROAD UPR TROF OVR THE WRN THIRD OF THE U.S. AND A BROAD UPR RDG OVR THE ERN THIRD OF THE COUNTRY. THIS LEAVES NE WI IN A WARM AND POSSIBLY ACTIVE WEATHER PATN THRU THE MIDDLE OF NXT WEEK. UNKNOWN FACTORS ARE THE REMNANTS OF HRCN IVAN AND WHERE HRCN JEANNE TO BE LOCATED. THE UPR TROF IN THE PROCESS OF DIGGING INTO THE WEST COAST ON SAT AS THE UPR RDG STILL OVR THE MIDWEST. SFC HI PRES OVR ONTARIO SHOULD PROVIDE FOR A DECENT AMT OF SUNSHINE THO EXPECTED NE WNDS TO KEEP ERN WI A LITTLE COOLER THAN LOCATIONS WELL INLAND. DRY EASTERLY FETCH ON SUNDAY FROM RETREATING SFC HI EXPECTED TO BRING MORE SUNSHINE AND TEMPS A FEW DEGS WARMER THAN SAT AS SW FLOW ALOFT BECOMES ESTABLISHED. REMNANTS OF IVAN STILL EXPECTED TO BE AFFECTING THE SE U.S. AT THIS TIME SO NO AFFECT ON OUR WEATHER YET. MDLS PROG IVAN TO RAIN ITSELF OUT AND DISSIPATE SOMEWHERE OVR THE TN VLY BY MON. IT IS CONCEIVABLE THAT SOME MSTR FROM IVAN MAY GET PICKED UP BY INCREASING SOUTHERLY WNDS OVR THE MIDWEST AND HEAD TOWARD THE GREAT LKS. OTHERWISE...LACK OF ANY TRIGGER WL PRECLUDE PCPN MON WITH ABV NORMAL TEMPS. WL HAVE TO WATCH TO SEE IF ANY RENEGADE MSTR FROM IVAN CAN GET THIS FAR NORTH PER DGEX MDL...BUT FOR THE TIME BEING...PLAN ON KEEPING MON NGT DRY. ATTN ON TUE FOCUSES ON A FNTL BNDRY WHICH IS FCST TO APPROACH THE WRN GREAT LKS RGN. ANTICIPATE THE BNDRY TO SLOW ITS FORWARD PROGRESS AS IT ENCOUNTERS THE SFC RDG AXIS OVR THE ERN GREAT LKS. CURRENT THINKING IS THAT ANY PCPN CHC WOULD ONLY BE ABLE TO REACH CNTRL WI THUS WL REMOVE POPS FOR ERN WI ON TUE. BNDRY PROGGED TO THEN NUDGE INTO THE RGN ON WED. NEEDLESS TO SAY...SHWRS/TSTMS NEEDED IN FCST. TEMPS TO BE COOLER WITH PLENTY OF CLDS AND PCPN IN THE AREA. .GRB WATCHES/WARNINGS/ADVISORIES... NONE. && RDM/KALLAS WWW.CRH.NOAA.GOV/GRB
HAZARDOUS WEATHER OUTLOOK NATIONAL WEATHER SERVICE GREEN BAY WI 1245 PM CDT WED SEP 15 2004 WIZ005-010>013-018>022-030-031-035>040-045-048>050-073-074-160345- VILAS-ONEIDA-FOREST-FLORENCE-NORTHERN MARINETTE-SOUTHERN MARINETTE- LINCOLN-LANGLADE-MENOMINEE-NORTHERN OCONTO-SOUTHERN OCONTO-DOOR- MARATHON-SHAWANO-WOOD-PORTAGE-WAUPACA-OUTAGAMIE-BROWN-KEWAUNEE-WAUSHARA- WINNEBAGO-CALUMET-MANITOWOC- 1245 PM CDT WED SEP 15 2004 THIS HAZARDOUS WEATHER OUTLOOK IS FOR NORTH-CENTRAL AND NORTHEAST WISCONSIN. .DAY ONE...THIS AFTERNOON AND TONIGHT SEVERE THUNDERSTORMS ARE POSSIBLE THIS AFTERNOON AND EVENING IN CENTRAL AND NORTH CENTRAL WISCONSIN. A DEEPENING LOW PRESSURE SYSTEM WILL PASS THROUGH THE WESTERN GREAT LAKES REGION. WARM...MOIST AIR AHEAD OF THIS SYSTEM WILL PRODUCE SCATTERED THUNDERSTORMS THIS AFTERNOON AND EVENING ACROSS THE ENTIRE REGION. A LINE OF STRONG OR SEVERE THUNDERSTORMS MAY FORM IN WESTERN WISCONSIN DURING THE AFTERNOON HOURS AND MOVE INTO THE CENTRAL AND NORTHCENTRAL PORTIONS OF THE STATE DURING THE LATE AFTERNOON AND EARLY EVENING. STRONG WINDS AND TORNADOES COULD ACCOMPANY THESE THUNDERSTORMS. IN ADDITION TO THE THREAT OF SEVERE THUNDERSTORMS...A SMALL CRAFT ADVISORY IS IN EFFECT FOR THE NEARSHORE WATERS OF LAKE MICHIGAN. .DAYS TWO THROUGH SEVEN...THURSDAY THROUGH TUESDAY NO HAZARDOUS WEATHER IS EXPECTED AT THIS TIME. .SPOTTER INFORMATION STATEMENT... SPOTTER GROUP ACTIVATION HAS OCCURRED. RDM WWW.CRH.NOAA.GOV/GRB
PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE GREEN BAY WI
350 PM CDT WED SEP 15 2004
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION...ST.. ...SOURCE....
..REMARKS..
0346 PM MARINE TSTM WIND 10 NE GREEN BAY 44.61N 87.86W
09/15/2004 41 MPH BROWN WI MESONET
MEASURED AT THE GREEN BAY LIGHT ON THE BAY.
&&The national radar mosaic for the moment the first event began.
3 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: 5423662, 5423664, 5423663.