h. were estimated in the Grand Haven harbor.
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 GRR wrote it up.
A coastal observation station in Muskegon recorded a 36 knot wind gust, and wind gusts of around 40 m.p.h. were estimated in the Grand Haven harbor.
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 Grand Rapids, MI wrote its last area forecast discussion before the first event at Aug 2, 3:00 AM EST, 10 hours 35 minutes earlier.
AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE GRAND RAPIDS MI 400 AM EDT MON AUG 2 2004 .SHORT TERM... OUR MAIN SHORT TERM FCST CHALLENGE IS TO DETERMINE CHANCES OF CONVECTION AND TIMING IT INTO OUR AREA TODAY INTO TUESDAY. AT 06Z IR SAT IMAGERY AND SFC OBS INDICATE MOSTLY CLEAR SKIES ACROSS OUR CWA. IR SAT TRENDS SUGGEST WELL START THE DAY OFF WITH A GOOD DEAL OF SUNSHINE WHICH WILL HELP TO QUICKLY BOOST TEMPS THROUGH THE 70S INTO THE 80S. WE WILL LEAN TOWARDS THE MILDER MAV GUIDANCE NUMBERS AND FEEL TEMPS IN MANY LOCATIONS WILL REACH THE MID TO PERHAPS UPPER 80S WITH A GOOD DEAL OF SUN AND SW FLOW. DRY CONDITIONS SHOULD PERSIST THROUGH THE MORNING. 10KM RUC GUIDANCE INDICATES A STRONG H5 VORT MAX WILL GRADUALLY MOVE SE FROM THE DAKOTAS INTO MN AND WI. THIS VORT IS TRIGGERING CONVECTION OVER THE DAKOTAS EARLY THIS A.M. OUR AREA WILL BEGIN TO GET INTO SOME PRETTY STRONG PVA THIS AFTERNOON. THAT COMBINED WITH ALL THE INSTABILITY GENERATED BY THEN (SB CAPES 2,000-3,000 J/KG, LIS -2 TO -4, TOTAL TOALS INTO THE 50S) WILL RESULT IN CONVECTIVE DEVELOPMENT OVER OUR AREA. WE BELIEVE CONVECTION WILL CONTINUE TONIGHT AS THE LLJ KICKS IN OFF TO OUR WEST. THIS WILL LIKELY TRIGGER MCS FORMATION THAT COULD PROPOGATE INTO OUR AREA (HIGH PW VALUES STILL IN PLACE AS WELL AS NICE 500 MB HEIGHT AND 1000-500 MB THICKNESS DIFFLUENCE). WELL CONTINUE TO HAVE A CHANCE FOR CONVECTION INTO TUESDAY OVER OUR SOUTHERN CWA CLOSER TO THE QUASI-STATIONARY BOUNDARY ACROSS SOUTH CENTRAL IL/IN. WE ARE COMPLETELY THROWING OUT 00Z GFS GUIDANCE SINCE IT IS SUFFERING FROM SERIOUS CONVECTIVE FEEDBACK PROBLEMS AND IS DEVELOPING A SPURIOUS SFC LOW NEAR ORD TUESDAY NIGHT AS A RESULT. THEREFORE, FAVORING THE ETA SOLUTION, WE BELIEVE ALL CONVECTION WILL BE FOCUSED WELL SOUTH OF OUR AREA BY TUESDAY NIGHT CLOSER TO THE QUASI-STATIONARY BOUNDARY. THE SFC HIGH PRESSURE RIDGE TO OUR NW WILL NUDGE IN HERE AND KEEP OUR AREA DRY FROM TUESDAY NIGHT THROUGH WEDNESDAY NIGHT. THE PRIMARY SVR WX THREATS FROM THIS AFTERNOON THROUGH TONIGHT WILL BE FOR HAIL AND PERHAPS A FEW HIGH WIND GUSTS. WE NOTED A FAIR AMOUNT OF HAIL REPORTS UPSTREAM OF OUR AREA TODAY WHERE VERY STEEP MID LEVEL LAPSE RATES WERE NOTED. THE THREAT FOR HIGH WIND GUSTS IS A BIT LESS OF A CONCERN, BUT WE CANNOT RULE IT OUT. WE NOTICED SEVERAL REPORTS OF HIGH WIND GUSTS WITH CONVECTION UPSTREAM YESTERDAY, AND WE ALSO NOTED THAT THE LLJ EARLY THIS A.M. IN IOWA (ABOUT 40 KTS 2 KFT AGL, DERIVED FROM A PROFILER) IS MUCH STRONGER THAN MODEL LOW LEVEL WIND FIELDS PROGGED IT TO BE. SO, WE FEEL MODEL GUIDANCE WIND FIELDS MAY BE UNDERDONE AGAIN FOR LATER TODAY AND TONIGHT. .LONG TERM... THE MEDIUM RANGE MODELS ARE IN DECENT AGREEMENT IN FORMING AN UNSEASONABLY DEEP UPPER TROUGH/LOW OVER THE EASTERN US FOR THE END OF THE WEEK. WILL CONTINUE TO LOWER TEMPERATURES AS THIS SCENARIO HAS BEEN PERSISTENT. WILL FEATURE WELL BELOW NORMAL TEMPERATURES. AS FOR PRECIPITATION...RIGHT NOW IT LOOKS DRY FOR THURSDAY INTO SATURDAY WITH A COLD NORTHERLY FLOW IN CONTROL. IF IT DOES GET AS COLD AS THE GFS SUGGESTS...WE MAY SEE SOME LAKE EFFECT CLOUDS MOVING IN FOR FRIDAY. && .GRR WATCHES/WARNINGS/ADVISORIES...NONE. && LAURENS MJS
HAZARDOUS WEATHER OUTLOOK NATIONAL WEATHER SERVICE GRAND RAPIDS MI 1010 AM EDT MON AUG 2 2004 LMZ843>849-MIZ037>040-043>046-050>052-056>059-064>067-071>073-031004- ALLEGAN-BARRY-CALHOUN-CLARE-CLINTON-EATON-GRATIOT-INGHAM-IONIA- ISABELLA-KALAMAZOO-KENT-LAKE-MASON-MECOSTA-MONTCALM-MUSKEGON-NEWAYGO- OCEANA-OSCEOLA-OTTAWA-VAN BUREN- NEW BUFFALO TO MANISTEE, MI 1010 AM EDT MON AUG 2 2004 .DAY ONE...TODAY AND TONIGHT THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS THIS AFTERNOON AND EVENING. SCATTERED THUNDERSTORMS ARE POSSIBLE THIS AFTERNOON...AND A LINE OF THUNDERSTORMS MAY MOVE ACROSS LAKE MICHIGAN THIS AFTERNOON AND ARRIVE IN SOUTHWEST LOWER MICHIGAN BY LATE AFTERNOON OR EARLY EVENING. THE MAIN THREAT WITH THESE STORMS WILL BE WINDS OF 60 MPH AND HAIL TO ONE INCH IN DIAMETER. HEAVY RAIN AND FREQUENT CLOUD TO GROUND LIGHTNING ARE ALSO POSSIBLE FROM THESE STORMS. THE AVERAGE STORM MOTION WILL BE EAST AT 40 MPH. .DAYS TWO THROUGH SEVEN...TUESDAY THROUGH SUNDAY THUNDERSTORMS ARE POSSIBLE MAINLY SOUTH OF INTERSTATE 96 ON TUESDAY AS A COLD FRONT SLIPS SOUTH. SEVERE WEATHER IS NOT FORECASTED WITH THESE STORMS. COOLER AND MORE STABLE AIR WILL FILTER IN BEHIND THIS FRONT FOR THE REMAINDER OF THE WEEK. .SPOTTER INFORMATION STATEMENT... SPOTTER ACTIVATION MAY BE NEEDED LATE THIS AFTERNOON OR THIS EVENING. OSTUNO
SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE GRAND RAPIDS MI
212 PM EDT MON AUG 2 2004
MIZ037>040-043>046-050>052-056>059-064>067-071>074-022300-
ALLEGAN-BARRY-CALHOUN-CLARE-CLINTON-EATON-GRATIOT-INGHAM-IONIA-
ISABELLA-JACKSON-KALAMAZOO-KENT-LAKE-MASON-MECOSTA-MONTCALM-MUSKEGON-
NEWAYGO-OCEANA-OSCEOLA-OTTAWA-VAN BUREN-
212 PM EDT MON AUG 2 2004
THE STORM PREDICTION CENTER HAS ISSUED A SEVERE THUNDERSTORM WATCH
FOR ALL OF SOUTHWEST LOWER MICHIGAN EFFECTIVE UNTIL 700 PM EDT
MONDAY EVENING. THIS WATCH INCLUDES THE FOLLOWING COUNTIES
IN WEST CENTRAL MICHIGAN
MASON...LAKE...OCEANA...NEWAYGO AND MUSKEGON
IN CENTRAL MICHIGAN
OSCEOLA...CLARE...ISABELLA...MECOSTA...MONTCALM AND GRATIOT
IN SOUTHWEST MICHIGAN
KENT...ALLEGAN...BARRY...KALAMAZOO...VAN BUREN AND OTTAWA
IN SOUTH CENTRAL MICHIGAN
IONIA...CLINTON...INGHAM...EATON...JACKSON AND CALHOUN
THIS WATCH INCLUDES THE ADJOINING COASTAL WATERS OF AFFECTED
LAKESHORE COUNTIES.
RG3 marine thunderstorm wind. Local standard time, as filed.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Lake Michigan in 2004Every state in 2004This day in weather history
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 2026-10-01. Each event’s entry at NCEI: 5419616, 5419617, 5419618.