1 flood, as filed by the National Weather Service.
Every event with a place to put it; 1 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 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 May 20, 7:25 PM EST, 5 hours earlier.
AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE DETROIT/PONTIAC MI 825 PM EDT THU MAY 20 2004 .UPDATE... EXPECT CONVECTIVE TRENDS TO INCREASE OVER SE MICHIGAN AS THE NIGHT WEARS ON. EARLY EVENING LAZY CONVECTION WILL GIVE WAY TO MORE ROBUST STORMS AS THE SURFACE COLD FRONT MOVES THROUGH THE REGION WITH AT LEAST NEUTRAL SUPPORT FROM MID AND UPPER LEVEL FEATURES. THE LATEST RADAR TRENDS SHOW THE COMPLEX OVER IA/WI/IL DEVELOPING EAST ALONG THE SURFACE FRONT TOWARD SW LOWER MI. AS THIS EVOLVES INTO MORE OF AN MCS, IT WILL TAKE CARE OF ANY REMAINING CAP AROUND 700 MB AS IT PROPAGATES EASTWARD DURING THE NIGHT. STORMS WILL STAY SURFACE BASED FOR A WHILE WITH CAPE AROUND 2000 J/KG HELPING TO MAINTAIN SOME CONCERN FOR SEVERE WEATHER WHEN COMBINED WITH SHEAR AROUND 30 M/S IN THE 0-6KM LAYER. LATER ON, THERE COULD BE A WEAKENING TREND AS THE FRONT MOVES SOUTH AND THE LOW LEVEL JET VEERS TO A LESS FAVORABLE FLOW TO SUPPORT ELEVATED CONVECTION. FORECAST UPDATE WILL GO WITH LIKELY/NUMEROUS COVERAGE FROM FLINT TO PORT HURON AND SOUTH, AND WILL KEEP SCATTERED COVERAGE TO THE NORTH. && BT .PREV DISCUSSION... ISSUED AT 310 PM TODAY AS HAS BEEN THE CASE THUS FAR, MODELS STRUGGLING WITH CONVECTION. EARLY MORNING MCS QUICKLY DISSIPATED AND DEVELOPED A WAKE LOW WHICH PRODUCED WIND GUSTS TO 30-35KTS LATE THIS MORNING. RESIDUAL LOW LEVEL STRATUS REMAINS IN PLACE AND WITH WARM ADVECTION ALOFT, IT SEEMS WE ARE CAPPED AT THE MOMENT. HOWEVER, A FEW DYNAMICAL PLAYERS LOOK TO BE COMING TOGETHER THE NEXT SEVERAL HOURS. FIRST IS 500/300MB JET RACING ACROSS WISCONSIN/U.P. WITH ENTRANCE REGION ACROSS IOWA/NORTHERN ILLINOIS/SOUTHERN WISCONSIN. SECOND IS A COLD FRONT DRAPED FROM THE DOOR PENINSULA TO NEAR KMCI WITH IMPRESSIVE THETA-E AIR AHEAD OF IT WITH DEWPOINTS INTO THE LOWER 70S (PER MSAS AND HOURLY RUC ANALYSIS). LASTLY, A WEAK MID LEVEL WAVE SEEN IN THE H2O VAPOR LOOP APPROACHING THE STATE OF IOWA. HI-RES 1KM RSO VISIBLE HAS RECENTLY INDICATED ACCAS/TCU DEVELOPING OVER IOWA AND RACING EAST TOWARD THE BORDER OF WISCONSIN/ILLINOIS. WE EXPECT CONVECTIVE INITIATION ACROSS THIS REGION THEN PROPAGATE EAST PER THE CORFIDI VECTORS AND 850-300MB THICKNESSES. LATEST RUN OF THE TAQ-RUC SUGGESTS THIS AS WELL AND WILL FOLLOW THIS IDEA FOR NOW. SYNOPTIC FEATURES IN THE NCEP SUITE SUGGEST THE UPSTREAM COLD FRONT WILL SLOWLY MIGRATE SOUTH THIS EVENING AND CLEAR THE STATE BY 06Z. CONVECTIVE PARAMETERS ARE IMPRESSIVE WITH FORECAST SURFACE CAPES OVER 4000 J/KG AND SURFACE BASED LI/S -8C. ENERGY HELICITY INDICES CLOSE TO 3, WHICH IS QUITE HIGH, WITH HELICITIES OVER 100 M2/S2. MOST OF THESE PARAMETERS ARE ALONG AND SOUTH OF M59. SO SEVERE WEATHER IS STILL A POTENTIAL THIS EVENING UNTIL FROPA. THEREAFTER...HIGH PRESSURE CURRENTLY CENTERED OVER LAKE WINNIPEG (1026 MB) OOZES SOUTH ACROSS THE GREAT LAKES AND THE FRONT SHOULD BE SOUTH OF THE STATE LINE...BUT NOT FOR LONG. IMPRESSIVE MOISTURE TRANSPORT AND 850-700MB THETA-E ADVECTION ACROSS THE MISSISSIPPI RIVER VALLEY WITH LOW LEVEL JET NEAR 50KTS ON FRIDAY WILL LIKELY DEVELOP/ENHANCE MCS WITH FRONT LIFTING NORTH AS A WARM FRONT. THIS MAY FOCUS AND/OR ASSIST WITH THE TRACK OF THE MCS ACROSS THE STATE ONCE AGAIN FRIDAY. AS TROF DIGS A BIT FURTHER ACROSS THE ROCKIES, THIS WILL BUCKLE THE FLOW DOWNSTREAM AND ALLOW THIS FRONT TO LIFT NORTH THRU THE DAY. THIS IS WELL SUMMARIZED IN THE SWODY2. UNFORTUNATELY, WE REMAIN STUCK IN THIS PATTERN INTO THE WEEKEND WITH THE PLACEMENT OF THE FRONT STILL IN QUESTION. MODELS ARE TRENDING TO FOCUS ALONG I69 WITH PERSISTENT MCS AND OTHER CLUSTERS OF STORMS RIDING ALONG THE FRONT. SOUTH OF THIS FRONT, TEMPERATURES HAVE A CHANCE TO CLIMB WELL INTO THE 80S WITH SURFACE DEWPOINTS INTO THE 60S. WE MIGHT REMAIN CAPPED SOUTH OF I69 WITH 700MB TEMPS CLIMBING TOWARD 10C. INTO THE EXTENDED PERIOD, THE GFS IS TRENDING TOWARD SURFACE LOW DEVELOPMENT AND TRACKING THIS ACROSS THE STATE ON SUNDAY WITH A RESPET FOR THE REGION EARLY NEXT WEEK. AS MENTIONED YESTERDAY, NAO IS FORECAST TO BECOME NEGATIVE AND TROF DIGS FURTHER SOUTH INTO NEXT WEEK. THIS MAY SET THE STAGE FOR A COOL HOLIDAY WEEKEND WITH A CHANCE OF SHOWERS. && .DTX WATCHES/WARNINGS/ADVISORIES...NONE. && BGM EXPERIMENTAL GRAPHICAL FORECASTS ARE AVAILABLE ONLINE AT HTTP://WWW.CRH.NOAA.GOV/DTX (ALL LOWER CASE)
HAZARDOUS WEATHER OUTLOOK FOR SOUTHEAST MICHIGAN NATIONAL WEATHER SERVICE DETROIT/PONTIAC MI 1050 PM EDT THU MAY 20 2004 MIZ047>049-053>055-211000- BAY-HURON-MIDLAND-SAGINAW-SANILAC-TUSCOLA- 1050 PM EDT THU MAY 20 2004 THIS HAZARDOUS WEATHER OUTLOOK IS FOR TRI-CITIES AND THUMB REGION. .DAY ONE...TONIGHT NO HAZARDOUS WEATHER IS ANTICIPATED. .DAY TWO THROUGH SEVEN...FRIDAY THROUGH WEDNESDAY SCATTERED THUNDERSTORMS ARE EXPECTED FRIDAY AFTERNOON THROUGH SUNDAY NIGHT. THERE IS A SLIGHT CHANCE OF SEVERE WEATHER FRIDAY...SATURDAY AND SUNDAY. SOME OF THESE STORMS WILL PRODUCE VERY HEAVY RAINFALL. THIS MAY LEAD TO LOCALIZED FLOODING. THE WARM FRONT WILL LIFT NORTH ACROSS THE REGION ON FRIDAY...THEN LINGER OVER SOUTHERN MICHIGAN THROUGH THE REST OF THE WEEKEND. THIS WILL RESULT IN A PROLONGED PERIOD OF SCATTERED THUNDERSTORMS ACROSS THE REGION. THERE IS ALSO A CHANCE OF THUNDERSTORMS ON TUESDAY AS A COLD FRONT MOVES THROUGH THE AREA. .SPOTTER INFORMATION STATEMENT... DISPATCHERS...PLEASE NOTIFY YOUR EMERGENCY MANAGERS IMMEDIATELY. SPOTTER ACTIVATION IS NOT ANTICIPATED. MIZ060>063-068>070-075-076-082-083-211000- GENESEE-LAPEER-LENAWEE-LIVINGSTON-MACOMB-MONROE-OAKLAND-SHIAWASSEE- ST. CLAIR-WASHTENAW-WAYNE- 1050 PM EDT THU MAY 20 2004 THIS HAZARDOUS WEATHER OUTLOOK IS FOR SOUTHEAST MICHIGAN. .DAY ONE...TONIGHT SEVERE THUNDERSTORM WATCH NUMBER 226 IN EFFECT UNTIL 3 AM. SCATTERED TO NUMEROUS THUNDERSTORMS WILL DEVELOP OVERNIGHT. SOME OF THESE STORMS MAY BE SEVERE...CAPABLE OF PRODUCING WIND GUSTS TO 70 MPH AND HAIL TO AROUND ONE INCH IN DIAMETER. THUNDERSTORMS WILL ALSO PRODUCE VERY HEAVY RAINFALL...WHICH COULD LEAD TO LOCALIZED FLOODING. THUNDERSTORM MOVEMENT WILL MOVE EAST AT 30 MPH. A COLD FRONT WILL CONTINUE TO SLIDE SOUTH THROUGH THE AREA... PROVIDING THE FOCUSING THE THUNDERSTORM ACTIVITY. .DAY TWO THROUGH SEVEN...FRIDAY THROUGH WEDNESDAY SCATTERED THUNDERSTORMS ARE EXPECTED FRIDAY MORNING THROUGH SUNDAY NIGHT. THERE IS A SLIGHT CHANCE OF SEVERE WEATHER FRIDAY...SATURDAY AND SUNDAY. SOME OF THESE STORMS WILL ALSO PRODUCE VERY HEAVY RAINFALL. THIS MAY LEAD TO LOCALIZED FLOODING. THE WARM FRONT WILL LIFT NORTH ACROSS THE REGION ON FRIDAY...THEN LINGER OVER SOUTHERN MICHIGAN THROUGH THE REST OF THE WEEKEND. THIS WILL RESULT IN THE PROLONGED PERIOD OF SCATTERED THUNDERSTORMS ACROSS THE REGION. THERE IS ALSO A CHANCE OF THUNDERSTORMS ON TUESDAY AS A COLD FRONT MOVES THROUGH THE AREA. .SPOTTER INFORMATION STATEMENT... DISPATCHERS...PLEASE NOTIFY YOUR EMERGENCY MANAGERS IMMEDIATELY. SPOTTER ACTIVATION HAS OCCURRED. SF
PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE DETROIT/PONTIAC MI
1241 AM EDT FRI MAY 21 2004
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION...ST.. ...SOURCE....
..REMARKS..
1229 AM HAIL 5 E ANN ARBOR 42.28N 83.63W
05/21/2004 1.00 INCH WASHTENAW MI TRAINED SPOTTER
&&
RBPPRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE DETROIT/PONTIAC MI
1244 AM EDT FRI MAY 21 2004
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION...ST.. ...SOURCE....
..REMARKS..
1241 AM FUNNEL CLOUD 2 ESE YPSILANTI 42.23N 83.58W
05/21/2004 WASHTENAW MI TRAINED SPOTTER
WALL CLOUD REPORTED AT TEXTILE AND MCKEAN.
&&
RBPPRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE DETROIT/PONTIAC MI
1252 AM EDT FRI MAY 21 2004
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION...ST.. ...SOURCE....
..REMARKS..
1251 AM HAIL 2 ENE YPSILANTI 42.26N 83.58W
05/21/2004 0.75 INCH WASHTENAW MI TRAINED SPOTTER
&&
RBPPRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE DETROIT/PONTIAC MI
102 AM EDT FRI MAY 21 2004
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION...ST.. ...SOURCE....
..REMARKS..
1230 AM HAIL ROMULUS 42.22N 83.37W
05/21/2004 0.75 INCH WAYNE MI TRAINED SPOTTER
1253 AM TSTM WND GST 2 ESE SALINE 42.16N 83.74W
05/21/2004 60 MPH WASHTENAW MI TRAINED SPOTTER
&&
RBPPRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE DETROIT/PONTIAC MI
106 AM EDT FRI MAY 21 2004
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION...ST.. ...SOURCE....
..REMARKS..
0103 AM HAIL 2 NW MILAN 42.11N 83.71W
05/21/2004 1.00 INCH WASHTENAW MI FIRE DEPT/RESCUE
&&
RBPSPECIAL WEATHER STATEMENT NATIONAL WEATHER SERVICE DETROIT/PONTIAC MI 119 AM EDT FRI MAY 21 2004 MIZ060>063-068>070-210700- GENESEE-LAPEER-LIVINGSTON-MACOMB-OAKLAND-SHIAWASSEE-ST. CLAIR- 119 AM EDT FRI MAY 21 2004 SEVERE THUNDERSTORM WATCH NUMBER 226 HAS BEEN CANCELLED FOR THE FOLLOWING COUNTIES... GENESEE...LAPEER...LIVINGSTON...MACOMB...OAKLAND...SHIAWASSEE... AND ST. CLAIR. MIZ075-076-082-083-210700- LENAWEE-MONROE-WASHTENAW-WAYNE- 119 AM EDT FRI MAY 21 2004 SEVERE THUNDERSTORM WATCH NUMBER 226 REMAINS IN EFFECT UNTIL 3 AM FOR THE FOLLOWING COUNTIES... LENAWEE...MONROE...WASHTENAW AND WAYNE. RBP
The national radar mosaic for the moment the first event began.
1 flood. Local standard time, as filed.
The Ecorse Creek at Dearborn Heights went above its 8 foot flood stage at 1225 am EST on the 21st. The river crested at 8.44 feet at 215 am EST on the 21st, then fell back below flood stage at 430 am EST on the 21st.
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, May 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: 5400171.