1 thunderstorm wind, as filed by the National Weather Service.
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 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 Detroit, MI wrote its last area forecast discussion before the first event at Aug 9, 2:20 PM EST, 7 hours 6 minutes earlier.
AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE DETROIT/PONTIAC MI 320 PM EDT MON AUG 9 2004 .DISCUSSION... CONVECTIVE TRENDS AND SEVERE WEATHER POTENTIAL WILL BE THE FIRST CONCERN EARLY IN THIS FORECAST FOLLOWED BY THE COOLING TREND FOR THE REST OF THIS WEEK. STORMS OVER CENTRAL LOWER MICHIGAN HAVE BEEN ELEVATED ALL DAY AS THE LOW LEVEL MOIST AXIS WORKS INTO THE REGION. THERE STILL COULD BE SOME SURFACE BASED DEVELOPMENT AS A PREFRONTAL TROF FORMS IN THE LEE OF LAKE MICHIGAN THIS AFTERNOON AND EARLY EVENING AS STRONGER DIFLUENT UPPER FLOW MOVES OVERHEAD. THIS IS ADVERTISED BY THE 12Z MODELS BUT WILL BE STRONGLY DEPENDENT ON THE STRENGTH OF SURFACE CONVERGENCE. INSTABILITY WILL BE ADEQUATE WITH A GENEROUS SURFACE PARCEL OF 81/66F OFFERING CAPE IN THE 2000-2500 J/KG RANGE. THE 12Z ETA THEN CONTINUES TO DEVELOP ANOTHER ROUND OF STORMS ALONG THE COLD FRONT AS THE UPPER LOW MOVES THROUGH LOWER MICHIGAN. THE DYNAMIC FORCING ASSOCIATED WITH THIS SYSTEM, ALONG WITH LINGERING BOUNDARY LAYER INSTABILITY, WILL GIVE US OUR BEST CHANCE OF SEVERE WEATHER. EVEN AN ELEVATED PARCEL WILL HAVE CAPE AROUND 1800 J/KG BY 03Z THIS EVENING TO GO ALONG WITH 0-3KM SHEAR OF 50 KNOTS AND 0-3KM HELICITY NEAR 200 M2/S2. THE HODOGRAPH IS NOT VERY LONG ABOVE 3 KM, SO EXPECTING THE CONVECTIVE MODE TO BE LINEAR WITH DAMAGING WIND THE MAIN HAZARD. A WELL-DEFINED DRY SLOT IS ALSO SHOWN ON SATELLITE IMAGERY WHICH WILL CONTRIBUTE TO NEGATIVE BUOYANCY IN DOWNDRAFTS AND TO HAIL POTENTIAL. THE STORMS ASSOCIATED WITH THE FRONT WILL EXIT TO OUR EAST SHORTLY AFTER MIDNIGHT, AND THE FRONT ITSELF WILL EXIT SE MICHIGAN BY SUNRISE. AFTER THAT, THERE IS GOOD MODEL AGREEMENT MAINTAINING SEPARATION BETWEEN THIS WAVE AND THE NEXT MOVING IN FROM THE PLAINS ON TUESDAY. THIS WILL REINFORCE THE DRY SLOT OVER SOUTHERN LOWER MICHIGAN WITH SOME SUBSIDENCE BETWEEN THE SYSTEMS. THIS, ALONG WITH STRONG NEGATIVE THETA-E ADVECTION BELOW 700 MB SUGGESTS NO MORE THAN ISOLATED SHOWERS AND STORMS OVER THE CENTRAL AND NORTHERN PORTIONS OF OUR AREA. IF IT WERE NOT FOR SOME SNEAKY SURFACE DEWPOINTS AROUND 60F UPSTREAM, WE MIGHT BE ABLE TO RULE OUT PRECIP COMPLETELY ON TUESDAY, INSTEAD WELL HOLD OUT WITH ISOLATED AND LET DAYTIME HEATING WORK ON THE BOUNDARY LAYER. THE NEXT NORTHERN PLAINS WAVE WILL MOVE INTO SE MICHIGAN LATE TUESDAY NIGHT. A RENEWED SURGE OF MID LEVEL MOISTURE WILL HELP WITH A CHANCE OF SHOWERS THROUGH WEDNESDAY, COMBINED WITH THE MID LEVEL COLD POOL AND DAYTIME HEATING. THIS WAVE WILL THEN HELP CARVE OUT THE LONG WAVE TROF OVER THE EASTERN STATES BY THURSDAY WITH YET ANOTHER WAVE MOVING INTO THE PLAINS FROM CENTRAL CANADA. THIS COMBINATION WILL KEEP THE CHANCE OF SHOWERS AND BELOW NORMAL TEMPS IN SE MICHIGAN. AMONG THE LONG RANGE MODELS, THE UKMET LOOKS TOO PROGRESSIVE ON THE UPPER AIR PATTERN BY FRIDAY. INSTEAD, THE SERIES OF UPPER WAVES WILL KEEP THE LONG WAVE TROF OVER THE EASTERN U.S. INTO THE WEEKEND. THE GFS SOLUTION LOOKS OK UNTIL SUNDAY AND IS IN LINE WITH THE ECMWF, CANADIAN, AND OUR LOCAL ETAXX. AS SUNDAY ROLLS AROUND, THE GFS STARTS TO MOVE THINGS ALONG WITH HIGH PRESSURE BUILDING INTO THE GREAT LAKES. THE NCEP ENSEMBLE MEMBERS SUGGEST A SLOWER DEPARTURE/FILLING OF THE LONG WAVE WHICH IS ALREADY BUILT INTO OUR FORECAST. SO NOT MUCH CHANGE TO THE WEEKEND CONDITIONS WITH BELOW NORMAL TEMPERATURES AND A CHANCE OF SHOWERS UNTIL MONDAY, WHICH WELL START OFF DRY AND GIVE THE RIDGE A CHANCE TO BUILD IN BY THEN, DEPENDING ON WHERE THE BLOCKING PATTERN DEVELOPS IN THE PACIFIC. WE PLAN TO KEEP AN EYE OUT FOR TRENDS TOWARD A FARTHER EAST AND WEAKER PATTERN THERE WHICH WOULD SPEED THINGS ALONG DOWNSTREAM HEADING INTO NEXT WEEK. && .DTX WATCHES/WARNINGS/ADVISORIES...NONE. && BT EXPERIMENTAL GRAPHICAL FORECASTS ARE AVAILABLE ONLINE AT HTTP://WWW.CRH.NOAA.GOV/DTX (ALL LOWER CASE)
HAZARDOUS WEATHER OUTLOOK NATIONAL WEATHER SERVICE DETROIT/PONTIAC MI 400 PM EDT MON AUG 9 2004 MIZ047-048-053-060-061-068-100900- BAY-GENESEE-LIVINGSTON-MIDLAND-SAGINAW-SHIAWASSEE- 400 PM EDT MON AUG 9 2004 THIS HAZARDOUS WEATHER OUTLOOK IS FOR TRI CITIES AND FLINT REGION. .DAY ONE...TONIGHT SCATTERED SHOWERS AND THUNDERSTORMS WILL BECOME MORE NUMEROUS AFTER 7 PM. THERE IS A SLIGHT CHANCE FOR SEVERE WEATHER WITH THESE STORMS. THE MAIN HAZARD WILL BE DAMAGING WINDS TO 65 MPH...BUT HAIL AROUND 1 INCH IN DIAMETER WILL ALSO BE POSSIBLE AS THE STORMS MOVE EAST AT 30 MPH. THE STORMS WILL EXIT SOUTHEAST MICHIGAN BETWEEN MIDNIGHT AND 2 AM. THUNDERSTORMS WILL CONTINUE TO DEVELOP ALONG AND AHEAD OF A STRONG COLD FRONT OVER WISCONSIN THAT WILL MOVE THROUGH THE GREAT LAKES OVERNIGHT. .DAY TWO THROUGH SEVEN...TUESDAY THROUGH SUNDAY AN ISOLATED THUNDERSTORM IS POSSIBLE TUESDAY AFTERNOON AND EVENING...BUT SEVERE WEATHER IS NOT EXPECTED. .SPOTTER INFORMATION STATEMENT... DISPATCHERS...PLEASE NOTIFY YOUR EMERGENCY MANAGER IMMEDIATELY. SPOTTER ACTIVATION MAY BE NEEDED TONIGHT. MIZ049-054-055-062-063-069-070-100900- HURON-LAPEER-MACOMB-OAKLAND-SANILAC-ST. CLAIR-TUSCOLA- 400 PM EDT MON AUG 9 2004 THIS HAZARDOUS WEATHER OUTLOOK IS FOR THE NORTHERN SUBURBS OF DETROIT INTO THE THUMB. .DAY ONE...TONIGHT SCATTERED SHOWERS AND THUNDERSTORMS WILL BECOME MORE NUMEROUS BETWEEN 8 PM AND 10 PM THIS EVENING. THERE IS A SLIGHT CHANCE FOR SEVERE WEATHER WITH THESE STORMS. THE MAIN HAZARD WILL BE DAMAGING WINDS TO 65 MPH...BUT HAIL AROUND 1 INCH IN DIAMETER WILL ALSO BE POSSIBLE AS THE STORMS MOVE EAST AT 30 MPH. THE STORMS WILL EXIT SOUTHEAST MICHIGAN BETWEEN MIDNIGHT AND 2 AM. THUNDERSTORMS WILL CONTINUE TO DEVELOP ALONG AND AHEAD OF A STRONG COLD FRONT OVER WISCONSIN THAT WILL MOVE THROUGH THE GREAT LAKES OVERNIGHT. .DAY TWO THROUGH SEVEN...TUESDAY THROUGH SUNDAY AN ISOLATED THUNDERSTORM IS POSSIBLE TUESDAY AFTERNOON AND EVENING...BUT SEVERE WEATHER IS NOT EXPECTED. .SPOTTER INFORMATION STATEMENT... DISPATCHERS...PLEASE NOTIFY YOUR EMERGENCY MANAGER IMMEDIATELY. SPOTTER ACTIVATION MAY BE NEEDED TONIGHT. MIZ075-076-082-083-100900- LENAWEE-MONROE-WASHTENAW-WAYNE- 400 PM EDT MON AUG 9 2004 THIS HAZARDOUS WEATHER OUTLOOK IS FOR METRO DETROIT AND FAR SOUTHEAST MICHIGAN. .DAY ONE...TONIGHT SCATTERED SHOWERS AND THUNDERSTORMS WILL BECOME MORE NUMEROUS BETWEEN 8 PM AND 10 PM THIS EVENING. THERE IS A SLIGHT CHANCE FOR SEVERE WEATHER WITH THESE STORMS. THE MAIN HAZARD WILL BE DAMAGING WINDS TO 65 MPH...BUT HAIL AROUND 1 INCH IN DIAMETER WILL ALSO BE POSSIBLE AS THE STORMS MOVE EAST AT 30 MPH. THE STORMS WILL EXIT SOUTHEAST MICHIGAN BETWEEN MIDNIGHT AND 2 AM. THUNDERSTORMS WILL CONTINUE TO DEVELOP ALONG AND AHEAD OF A STRONG COLD FRONT OVER WISCONSIN THAT WILL MOVE THROUGH THE GREAT LAKES OVERNIGHT. .DAY TWO THROUGH SEVEN...TUESDAY THROUGH SUNDAY NO HAZARDOUS WEATHER IS EXPECTED AT THIS TIME. .SPOTTER INFORMATION STATEMENT... DISPATCHERS...PLEASE NOTIFY YOUR EMERGENCY MANAGER IMMEDIATELY. SPOTTER ACTIVATION MAY BE NEEDED TONIGHT. BT
The national radar mosaic for the moment the first event began.
1 thunderstorm wind. Local standard time, as filed.
A trained spotter estimated a 60 mph thunderstorm wind gust.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Michigan in 2004Every state in 2004This day in weather historyWarnings in Michigan, August 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: 5414638.