An isolated severe thunderstorm developed during the afternoon hours.
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 episode as NWS DTX wrote it up.
An isolated severe thunderstorm developed during the afternoon hours.
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 Jul 22, 1:15 PM EST, 1 hour 40 minutes earlier.
AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE DETROIT/PONTIAC MI 215 PM EDT WED JUL 22 2009 .AVIATION... A FEW THERMAL GRADIENTS ARE SPIRALING NORTHWARD THROUGH THE CWA THIS AFTERNOON. THESE FEATURES HAVE BEEN HIGHLY ACTIVE ACROSS THE NORTHERN HALF OF THE FORECAST AREA...GENERATING NUMEROUS SHOWERS AND THUNDERSTORMS. LEFT THUNDER OUT OF THE TAFS FOR THE SOUTHERN SITES AS A HIGHER STABILITY AIRMASS IS FORECASTED TO LIFT ACROSS THE MI/OH STATELINE. THE INITIAL ACTIVITY IS EXPECTED TO WANE LATE THIS AFTERNOON AND EVENING WITH THE LOSS OF INSOLATION. LATER THIS EVENING...ADDITIONAL UPPER LEVEL MOISTURE AND ENERGY WILL LIFT NORTHWARD OUT OF THE OHIO RIVER VALLEY BRINGING CONTINUED CHANCES OF A STRATIFORM RAIN. AS THE LOW PRESSURE SYSTEM APPROACHES MICHIGAN...THE THREAT OF IFR CEILINGS CONDITIONS WILL INCREASE AFTER 06Z. SURFACE WINDS WILL OSCILLATE SOUTHERLY THIS AFTERNOON BEFORE RESPONDING MORE NORTHERLY OVERNIGHT. && .PREV DISCUSSION...ISSUED 417 AM EDT WED JUL 22 2009 SHORT TERM...TODAY TWO SEPARATE PRECIPITATION SYSTEMS ARE TAKING AIM FOR THE AREA EARLY THIS MORNING AS A BROKEN LINE OF SHOWERS IS HEADING NORTH NORTH EAST FROM THE WESTERN GREAT LAKES...WHILE ANOTHER AREA ACROSS THE WESTERN OHIO VALLEY IS HEADING NORTHEAST. WHILE IT APPEARS THE OHIO VALLEY PRECIP IS MOVING TOO SLOW TO AFFECT THE AREA TODAY...THE SCATTERED SHOWERS ACROSS LAKE MICHIGAN SHOULD MAKE IT INTO THE CWA AS THE DAY WEARS ON. IN ADDITION...A 500 MB TROF AND UPPER LEVEL DIVERGENCE ASSOCIATED WITH THE RIGHT REAR OF THE JET WILL ENHANCE PRECIP CHANCES THIS AFTERNOON AS THESE FEATURES TAKE ADVANTAGE OF DIURNAL HEATING. THEREFORE WILL STICK WITH THE HIGH CHANCY POPS THIS MORNING...WITH LIKELY POPS THIS AFTERNOON WHEN THE DYNAMICS BECOME MORE FAVORABLE. DESPITE THE DECENT DYNAMICS...INSTABILITY WILL AGAIN BE LOW WITH ONLY A FEW HUNDRED J/KG OF CAPE AT BEST WITH A VERY WEAK WIND FLOW UP THROUGH 500 MB. WITH ABUNDANT MOISTURE IN THE MIDDLE AND UPPER LEVELS...SOME HEAVY RAIN IS POSSIBLE...HOWEVER SEVERE WEATHER IS NOT EXPECTED WITH THE MEAGER INSTABILITY AND WIND FIELDS. DESPITE SIMILAR 850 MB TEMPERATURES...CLOUDS ARE RAPIDLY SPREADING INTO THE AREA FROM THE WEST AND SOUTHEASTERLY WINDS OFF THE LAKES ARE EXPECTED TODAY. THESE FACTORS WILL LEAD TO LOWER HIGH TEMPERATURES TODAY THAN PREVIOUS DAYS WITH HIGHS ONLY IN THE LOWER TO MIDDLE 70S. LONG TERM...TONIGHT THROUGH TUESDAY NEGATIVELY TILTED UPPER TROUGH WILL EXTEND FROM NORTH CENTRAL CANADA DOWN INTO THE SOUTHERN GREAT LAKES AS WE HEAD INTO THE TONIGHT PERIOD. AT THE SURFACE...LOW PRESSURE CURRENTLY OVER ARKANSAS/TENNESSEE WILL LIFT NORTHEAST INTO THE SOUTHERN GREAT LAKES OVERNIGHT. MODEL SOLUTIONS ARE STILL SHOWING QUITE A DEGREE OF VARIABILITY WITH REGARD TO TIMING AND EXACT TRACK THE CENTER OF THIS SYSTEM WILL TAKE...HOWEVER THERE REMAINS FAIR ENOUGH AGREEMENT WITH THE WESTERN END OF THE DEFORMATION ZONE OVERSPREADING SOUTHEAST MICHIGAN FOR A CONTINUATION OF CHANCE POPS WEST AND LIKELY POPS FOR THE FAR EAST. HOWEVER...ISENTROPIC ASCENT SHOWN ON 00Z GFS/NAM DOES LOOK LESS IMPRESSIVE AND FURTHER EAST (OVER ONTARIO) THAN IT DID IN PREVIOUS RUNS. MODEL SOUNDINGS LOOK SUFFICIENTLY MOIST THROUGHOUT THE NIGHT TO CARRY RAIN...BUT GIVEN GOOD STABILITY THROUGH THE SURFACE TO 600 MB LAYER THINK THE PROBABILITY FOR THUNDERSTORMS LOOKS TOO LOW TO KEEP IN FORECAST. STRONG UPPER SHORTWAVE TROUGHING OVER MICHIGAN THURSDAY WILL ONCE AGAIN BRING SCATTERED SHOWERS AND THUNDERSTORMS. EXPECT DEVELOPMENT WILL HAVE SOME DIURNAL COMPONENT AS STEEPENING LOW-LEVEL LAPSE RATES ALLOW INSTABILITY TO BECOME MAXIMIZED UNDER THE UPPER COLD POOL BY AFTERNOON. SHEAR WILL BE VERY WEAK...BUT WITH FREEZING LEVELS DROPPING TO BELOW 10000 FT AND MODEST SB CAPE VALUES FROM 500-1000 J/KG SHOWN BY NAM/GFS WOULD NOT BE SURPRISED TO SEE SOME SMALL HAIL. ATTENTION THEN BECOMES FOCUSED ON THE LARGER SYSTEM EXPECTED TO IMPACT THE AREA FRIDAY AND SATURDAY. THE FIRST HALF OF FRIDAY MAY END UP BEING FAIRLY QUIET AS BRIEF AND VERY WEAK SHORTWAVE RIDGING ALLOWS FOR BREAKS IN THE CLOUDS AND ALLOWS TEMPERATURES TO WARM INTO THE LOW 80S. STRONG SHORTWAVE ENERGY DROPPING DOWN OUT OF CENTRAL CANADA WILL THEN REINFORCE UPPER TROUGHING OVER THE EASTERN U.S. AND GREAT LAKES...AND SEND A STRONG SURFACE LOW PRESSURE SYSTEM ACROSS MICHIGAN ON FRIDAY NIGHT AND SATURDAY. 00Z MODELS HAVE COME TO A TIGHTER CONSENSUS WITH THE COLD FRONT PUSHING THROUGH SATURDAY AFTERNOON...PRECEDED BY A GOOD INFLUX OF MOISTURE FRIDAY NIGHT AS THE LOW LEVEL JET NOSES IN. WILL WANT TO KEEP AN EYE ON UPSTREAM DEVELOPMENT FRIDAY NIGHT AS MODELS ALL INDICATE VERY IMPRESSIVE UPPER DIFFLUENCE OVERLYING THE SURFACE FRONT JUST TO OUR WEST. GIVEN THIS...CONFIDENCE HAS INCREASED WITH SEEING A GOOD COVERAGE OF PRECIPITATION FRIDAY NIGHT AND FOR THE FIRST HALF OF SATURDAY. UPSTREAM DEVELOPMENT FRIDAY NIGHT WOULD REALLY HINDER DAYTIME INSTABILITY BY THE TIME OF COLD FRONTAL PASSAGE SATURDAY AFTERNOON...AND MAY HAVE TO LOOK FOR THE OVERNIGHT PERIOD TO ACTUALLY BE THE MOST ACTIVE. HOWEVER...WHETHER CONVECTION DEVELOPS OVERHEAD OR WHETHER WE SEE DEBRIS FROM UPSTREAM CONVECTION STILL REMAINS TO BE DETERMINED. LATEST SPOKE ROTATING THROUGH THE PERSISTENT GREAT LAKES TROUGH WILL LIFT NORTH INTO CANADA ON SUNDAY...WITH MODELS NOW INDICATING WE WILL REMAIN OUT OF TROUGHING ON MONDAY AS WELL. INDICATIONS (PER GFS/EURO) ARE THAT THIS WILL BE SHORT-LIVED HOWEVER AS MORE ENERGY DROPPING DOWN FROM CANADA ALLOWS THE TROUGH TO REFORM BY THE MIDDLE OF THE WEEK. THIS SHOULD ALLOW SOUTHEAST MICHIGAN TO DRY OUT SUNDAY AND MONDAY BEFORE RAIN CHANCES RETURN ON TUESDAY. HIGH TEMPERATURES THROUGHOUT THE EXTENDED PERIOD WILL REMAIN SEASONABLY COOL...HOWEVER WE WILL AT LEAST COME CLOSE TO NORMAL ON FRIDAY AS WARMER AIR SURGES INTO LOWER MICHIGAN AHEAD OF THE APPROACHING LOW PRESSURE SYSTEM. MARINE... A SLOW MOVING LOW PRESSURE SYSTEM ACROSS THE OHIO VALLEY WILL MOVE NORTHEAST INTO THE EASTERN GREAT LAKES TONIGHT...THEN NORTH TOWARDS JAMES BAY ON THURSDAY. MEANWHILE...ANOTHER LOW PRESSURE SYSTEM APPROACHING FROM THE PLAINS WILL MOVE INTO THE WESTERN GREAT LAKES FRIDAY...THEN INTO THE CENTRAL GREAT LAKES DURING THE WEEKEND. THESE LOW PRESSURE SYSTEMS WILL BRING AN EXTENDED PERIOD OF UNSETTLED WEATHER TO THE CENTRAL GREAT LAKES THROUGH THE WEEKEND. WHILE SMALL CRAFT CONDITIONS ARE NOT EXPECTED THROUGH FRIDAY...GUSTY SOUTHERLY WINDS ARE EXPECTED AS THE SECOND LOW MOVES INTO THE CENTRAL GREAT LAKES FRIDAY NIGHT AND EARLY SATURDAY. SMALL CRAFT CONDITIONS ARE POSSIBLE AS WINDS GUST TO 25 KNOTS DURING THIS PERIOD. CONDITIONS WILL BE MONITORED CLOSELY FOR ANY POSSIBLE FUTURE HEADLINES. && .DTX WATCHES/WARNINGS/ADVISORIES... MI...NONE. LAKE HURON...NONE. LAKE ST CLAIR...NONE. MI WATERS OF LAKE ERIE...NONE. && AVIATION.....CB SHORT TERM...KURIMSKI LONG TERM....HLO MARINE.......KURIMSKI YOU CAN OBTAIN YOUR LATEST NATIONAL WEATHER SERVICE FORECASTS ONLINE AT WWW.WEATHER.GOV/DETROIT (ALL LOWER CASE).
HAZARDOUS WEATHER OUTLOOK NATIONAL WEATHER SERVICE DETROIT/PONTIAC MI 429 AM EDT WED JUL 22 2009 MIZ047>049-053>055-060>063-068>070-075-076-082-083-230900- MIDLAND-BAY-HURON-SAGINAW-TUSCOLA-SANILAC-SHIAWASSEE-GENESEE-LAPEER- ST. CLAIR-LIVINGSTON-OAKLAND-MACOMB-WASHTENAW-WAYNE-LENAWEE-MONROE- 429 AM EDT WED JUL 22 2009 THIS HAZARDOUS WEATHER OUTLOOK IS FOR ALL OF SOUTHEAST MICHIGAN. .DAY ONE...TODAY AND TONIGHT THERE IS A CHANCE OF THUNDERSTORMS THOUGH EARLY EVENING AS A LOW PRESSURE SYSTEM LIFTS INTO THE OHIO VALLEY. SEVERE WEATHER IS NOT ANTICIPATED...HOWEVER HIGH ATMOSPHERIC MOISTURE CONTENT AND SLOW MOVEMENT WILL BRING THE THREAT FOR HEAVY RAINFALL WITH THESE STORMS. THUNDERSTORM MOVEMENT WILL BE TO THE NORTH AT AROUND 15 MPH. .DAYS TWO THROUGH SEVEN...THURSDAY THROUGH TUESDAY CHANCES FOR THUNDERSTORMS WILL CONTINUE THURSDAY THROUGH SUNDAY AS A SERIES OF DISTURBANCES RIDE THROUGH AN UPPER LEVEL TROUGH THAT WILL REMAIN IN PLACE OVER THE GREAT LAKES. AFTER A BREAK EARLY NEXT WEEK...THUNDERSTORM CHANCES WILL RETURN ON TUESDAY. .SPOTTER INFORMATION STATEMENT... SPOTTER ACTIVATION WILL NOT BE NEEDED TODAY AND TONIGHT. LCZ422-423-460-LEZ444-LHZ361>363-421-422-441>443-462>464-230900- ST. CLAIR RIVER-DETROIT RIVER-LAKE ST. CLAIR- MICHIGAN WATERS OF LAKE ERIE FROM DETROIT RIVER TO NORTH CAPE MI- LAKE HURON FROM 5NM EAST OF MACKINAC BRIDGE TO PRESQUE ISLE LT BEYOND 5 NM OFF SHORE- LAKE HURON FROM PRESQUE ISLE LIGHT TO STURGEON POINT MI BEYOND 5NM OFF SHORE- LAKE HURON FROM STURGEON POINT TO ALABASTER MI BEYOND 5NM OFF SHORE- OUTER SAGINAW BAY SW OF ALABASTER TO PORT AUSTIN MI TO INNER SAGINAW BAY-INNER SAGINAW BAY SW OF POINT AU GRES TO BAY PORT MI- PORT AUSTIN TO HARBOR BEACH MI-HARBOR BEACH TO PORT SANILAC MI- PORT SANILAC TO PORT HURON MI- LAKE HURON FROM PORT AUSTIN TO HARBOR BEACH BEYOND 5NM OFF SHORE- LAKE HURON FROM HARBOR BEACH TO PORT SANILAC BEYOND 5NM OFF SHORE- LAKE HURON FROM PORT SANILAC TO PORT HURON BEYOND 5NM OFF SHORE- 429 AM EDT WED JUL 22 2009 THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF LAKE ERIE...LAKE HURON AND LAKE ST CLAIR. .DAY ONE...TODAY AND TONIGHT THERE IS A CHANCE OF THUNDERSTORMS THOUGH EARLY EVENING AS A LOW PRESSURE SYSTEM LIFTS INTO THE OHIO VALLEY. SEVERE WEATHER IS NOT ANTICIPATED...HOWEVER HIGH ATMOSPHERIC MOISTURE CONTENT AND SLOW MOVEMENT WILL BRING THE THREAT FOR HEAVY RAINFALL WITH THESE STORMS. THUNDERSTORM MOVEMENT WILL BE TO THE NORTH AT 10 TO 15 KNOTS. .DAYS TWO THROUGH SEVEN...THURSDAY THROUGH TUESDAY CHANCES FOR THUNDERSTORMS WILL CONTINUE THURSDAY THROUGH SUNDAY AS A SERIES OF DISTURBANCES RIDE THROUGH AN UPPER LEVEL TROUGH THAT WILL REMAIN IN PLACE OVER THE GREAT LAKES. AFTER A BREAK EARLY NEXT WEEK...THUNDERSTORM CHANCES WILL RETURN ON TUESDAY. .SPOTTER INFORMATION STATEMENT... SPOTTER ACTIVATION WILL NOT BE NEEDED TODAY AND TONIGHT. HLO YOU CAN OBTAIN YOUR LATEST NATIONAL WEATHER SERVICE FORECASTS ONLINE AT WWW.WEATHER.GOV/DETROIT (ALL LOWER CASE).
SPECIAL WEATHER STATEMENT NATIONAL WEATHER SERVICE DETROIT/PONTIAC MI 232 PM EDT WED JUL 22 2009 MIZ048-053-054-221930- BAY-SAGINAW-TUSCOLA- 232 PM EDT WED JUL 22 2009 ...SIGNIFICANT WEATHER ADVISORY... AT 231 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A STRONG THUNDERSTORM 4 MILES WEST OF VASSAR...MOVING NORTH AT 10 MPH. UP TO DIME SIZE HAIL...WINDS GREATER THAN 30 MPH...FREQUENT CLOUD TO GROUND LIGHTNING...BRIEF HEAVY DOWNPOURS...ARE POSSIBLE WITH THIS STORM. * THE THUNDERSTORM WILL BE NEAR... REESE AROUND 305 PM EDT... FAIRGROVE AND QUANICASSEE AROUND 330 PM EDT... GUSTY WINDS MAY CAUSE SMALL OBJECTS SUCH AS TRASH BINS TO BLOW AROUND. STAY AWAY FROM HIGH OBJECTS OUTDOORS SUCH AS TREES. SEEK SHELTER IN A STURDY STRUCTURE UNTIL THIS STORM HAS PASSED. MANN
SPECIAL WEATHER STATEMENT NATIONAL WEATHER SERVICE DETROIT/PONTIAC MI 250 PM EDT WED JUL 22 2009 MIZ053-221945- SAGINAW- 250 PM EDT WED JUL 22 2009 ...SIGNIFICANT WEATHER ADVISORY... AT 249 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A STRONG THUNDERSTORM OVER WEST CENTRAL SAGINAW COUNTY...MOVING NORTH AT 10 MPH. UP TO DIME SIZE HAIL...WINDS GREATER THAN 30 MPH...FREQUENT CLOUD TO GROUND LIGHTNING...BRIEF MODERATE DOWNPOURS...ARE POSSIBLE WITH THIS STORM. * THE THUNDERSTORM WILL BE NEAR... MERRILL AROUND 330 PM EDT... GUSTY WINDS MAY CAUSE SMALL OBJECTS SUCH AS TRASH BINS TO BLOW AROUND. STAY AWAY FROM HIGH OBJECTS OUTDOORS SUCH AS TREES. SEEK SHELTER IN A STURDY STRUCTURE UNTIL THIS STORM HAS PASSED. MANN
PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE DETROIT/PONTIAC MI
313 PM EDT WED JUL 22 2009
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE....
..REMARKS..
0310 PM HEAVY RAIN 5 S MERRILL 43.34N 84.34W
07/22/2009 M1.20 INCH SAGINAW MI TRAINED SPOTTER
15 MIN TOTAL
&&
ADODSONSPECIAL WEATHER STATEMENT NATIONAL WEATHER SERVICE DETROIT/PONTIAC MI 317 PM EDT WED JUL 22 2009 MIZ049-054-055-222015- HURON-SANILAC-TUSCOLA- 317 PM EDT WED JUL 22 2009 ...SIGNIFICANT WEATHER ADVISORY... AT 315 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED STRONG THUNDERSTORMS ALONG A LINE EXTENDING FROM AKRON TO 13 MILES SOUTH OF UBLY...MOVING NORTH AT 20 MPH. ONE HALF INCH DIAMETER HAIL...WINDS GREATER THAN 30 MPH...FREQUENT CLOUD TO GROUND LIGHTNING...BRIEF HEAVY DOWNPOURS...ARE POSSIBLE WITH THESE STORMS. * THUNDERSTORMS WILL BE NEAR... UNIONVILLE AND CASS CITY AROUND 325 PM EDT... GAGETOWN AROUND 335 PM EDT... SEBEWAING AROUND 340 PM EDT... OWENDALE AROUND 345 PM EDT... UBLY AND MINDEN AROUND 355 PM EDT... PIGEON AND ELKTON AROUND 410 PM EDT... 6 MILES SOUTH OF CASEVILLE AROUND 415 PM EDT... GUSTY WINDS MAY CAUSE SMALL OBJECTS SUCH AS TRASH BINS TO BLOW AROUND. STAY AWAY FROM HIGH OBJECTS OUTDOORS SUCH AS TREES. SEEK SHELTER IN A STURDY STRUCTURE UNTIL THESE STORMS HAVE PASSED. MANN
SPECIAL WEATHER STATEMENT NATIONAL WEATHER SERVICE DETROIT/PONTIAC MI 336 PM EDT WED JUL 22 2009 MIZ047-222030- MIDLAND- 336 PM EDT WED JUL 22 2009 ...SPECIAL WEATHER STATEMENT... AT 336 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A STRONG THUNDERSTORM 5 MILES SOUTH OF MIDLAND...MOVING NORTH AT 15 MPH. PEA SIZE HAIL...WINDS GREATER THAN 30 MPH...OCCASIONAL CLOUD TO GROUND LIGHTNING...BRIEF MODERATE DOWNPOURS...ARE POSSIBLE WITH THIS STORM. * THE THUNDERSTORM WILL BE NEAR... MIDLAND AROUND 355 PM EDT... GUSTY WINDS MAY CAUSE SMALL OBJECTS SUCH AS TRASH BINS TO BLOW AROUND. STAY AWAY FROM HIGH OBJECTS OUTDOORS SUCH AS TREES. SEEK SHELTER IN A STURDY STRUCTURE UNTIL THIS STORM HAS PASSED. MANN
SPECIAL WEATHER STATEMENT NATIONAL WEATHER SERVICE DETROIT/PONTIAC MI 345 PM EDT WED JUL 22 2009 MIZ049-222030- HURON- 345 PM EDT WED JUL 22 2009 ...SIGNIFICANT WEATHER ADVISORY... AT 344 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED STRONG THUNDERSTORMS ALONG A LINE EXTENDING FROM 10 MILES SOUTHWEST OF CASEVILLE TO UBLY...MOVING NORTH AT 30 MPH. PEA SIZE HAIL...WINDS GREATER THAN 30 MPH...FREQUENT CLOUD TO GROUND LIGHTNING...BRIEF HEAVY DOWNPOURS...ARE POSSIBLE WITH THESE STORMS. * THUNDERSTORMS WILL BE NEAR... PIGEON AND BAD AXE AROUND 350 PM EDT... CASEVILLE AROUND 405 PM EDT... KINDE AROUND 410 PM EDT... PORT AUSTIN AROUND 425 PM EDT... GUSTY WINDS MAY CAUSE SMALL OBJECTS SUCH AS TRASH BINS TO BLOW AROUND. STAY AWAY FROM HIGH OBJECTS OUTDOORS SUCH AS TREES. SEEK SHELTER IN A STURDY STRUCTURE UNTIL THESE STORMS HAVE PASSED. MANN
The Detroit radar (KDTX), 127 km away, was scanning. The volume nearest the first event began at 19:56 UTC.
1 thunderstorm wind. Local standard time, as filed.
Large tree limbs were reported blown down.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Michigan in 2009Every state in 2009This day in weather historyWarnings in Michigan, July 2009
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: 182247.