Thunderstorms moved into areas west of a line from Sigourney, IA to Dubuque, IA during the early evening hours of September 18th ahead of a cold front. |A small bowing echo line of storms moved through areas north and west of the Cedar Rapids area producing damaging winds between 60 and 80 mph.
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 DVN wrote it up.
Thunderstorms moved into areas west of a line from Sigourney, IA to Dubuque, IA during the early evening hours of September 18th ahead of a cold front. Moderate instability developed and humidity levels increased during the afternoon as temperatures rose into the middle 80s to near 90.|A small bowing echo line of storms moved through areas north and west of the Cedar Rapids area producing damaging winds between 60 and 80 mph.
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 Quad Cities, IA wrote its last area forecast discussion before the first event at Sep 18, 2:00 PM CST, 3 hours 13 minutes earlier.
AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE QUAD CITIES IA IL 300 PM CDT TUE SEP 18 2007 .SYNOPSIS... LATEST SFC ANALYSIS WAS INDICATING FRONTAL COMPLEX EXTENDING FROM NORTHWEST ONTARIO TO A WEAK SFC WAVE OVER FAR SOUTHWEST MN...THEN EXTENDING INTO SOUTHWEST CO. BROAD PRESSURE FALLS WERE LOCATED TO THE LEE OF THIS FEATURE...WITH MOST PRONOUNCED AREA IN FAR EASTERN KS JUST EAST OF THE MOST DECENT CONVECTIVE SYSTEM IN THE MIDWEST. W/V IMAGERY WAS INDICATING MAIN UPSTREAM WAVE OF CONSEQUENCE ROLLING ACRS FAR NORTHWEST KS AND THE NEB PANHANDLE. && .SHORT TERM...TONIGHT AND WEDNESDAY...PREFER THE 12Z GFS IN SPEED AND HANDLING OF INCOMING FRONT...ESPECIALLY NOW LOOKING AT THE NEW 12Z HI-RES ECMWF WHICH GENERALLY AGREES WITH THE GFS. PLACEMENT OF STOUT LOW TO MID LEVEL RIDGING ACRS THE SOUTHEAST AND EASTERN CONUS WILL DEFLECT THE WESTERN NEB VORT TO THE NORTHEAST AND THE BULK OF ITS CVA/FORCING WITH IT TONIGHT. MOST OF THE SHORT RANGE MODELS SHIFT LIFT MAX/POS OMEGAS FROM NORTHWEST INTO NORTH CENTRAL IOWA THIS EVENING...UP THROUGH NORTHWEST WI AND THEN DAMPENS THIS PROCESS AS IT MIGRATES EASTWARD OVERNIGHT INTO THE LOCAL FCST AREA. MIXING IN INSOLATION SECTOR JUST EAST-SOUTHEAST OF MAIN SHOWER/CLOUD SHIELD OVER EASTERN IA AND NORTHEAST MO HAS KEPT A LID ON SFC DPTS...BUT HEATING HAS MADE FOR RATHER STEEP LOW TO MID LEVEL LAPSE RATES. IF A FEW STORMS COULD DEVELOP AND MAKE IT INTO THE WEST CENTRAL OR NORTHEAST CWA THROUGH BEFORE 02Z OR SO...PROGGED LINGERING DOWNDRAFT CAPES SUGGEST THAT A STORM MAY BE ALLOWED TO MIX DOWN SOME OF THE BRISK AMBIENT LOW TO MID LEVEL WIND FIELD JUST TO THE LEE OF THE FRONTAL COMPLEX...WITH INSTABILITY REALLY WANING AFTER THAT. EVEN THOUGH SVR RISK LOOKS RATHER BLEAK...SOME MID LEVEL INSTABILITY IS SUGGESTED BY THE MODELS TO HOLD ON ALONG AND WEST OF THE MS RVR TO KEEP SHOWERS AND EMBEDDED THUNDER GOING THROUGH 06Z OR SO BEFORE THAT PARAMETER ALONG WITH ANY LINGERING FORCING WANE. THUS EXPECT SHOWERS AND SOME STORMS TO FALL APART AFTER MIDNIGHT EAST OF THE MS RVR...AND WILL TAPER OFF POPS ACCORDINGLY. WHILE THE NORTHWEST THIRD OF THE DVN CWA MAY RECEIVE FROM .25 UP TO HALF INCH OF RAINFALL ROUGHLY THROUGH 07Z/2 AM CDT...MUCH OF THE REST OF THE FCST AREA PROBABLY WILL RECEIVE A TENTH OF AN INCH OR LESS. ON WED...FRONT TO WEAKEN AND SLOWS AS IT ENCOUNTERS DEEPER RIDGING TO THE SOUTHEAST...POSSIBLY TAKING MUCH OF THE DAY TO CLEAR THE CWA. A FEW LINGERING POST FRONTAL SHOWERS MAY OCCUR THROUGH EARLY AFTERNOON ACRS THE SOUTHEAST HALF OF THE FCST AREA...BUT EXPECT SOME CLEARING ACRS THE NORTHWEST HALF. SOME LAG IN BETTER LLVL CAA SUGGESTS ANY CLEARING WITH SOME MIXING MAY HELP TEMPS RISE BACK TO AROUND 80 OR EVEN THE LOW 80S...BUT AREAS THAT REMAIN CLOUD COVERED WILL BE LIMITED TO THE 70S. ..12.. .LONG TERM...TUESDAY NIGHT THROUGH MONDAY... ABOVE NORMAL TEMPERATURES TRENDING MORE ACTIVE AND WET BY EARLY NEXT WEEK. PRIMARY GUIDANCE MORE CONSISTENT RUN TO RUN HI-RES ECMWF AND GFS AND ALSO GEFS. SOME INPUTS FROM NMA-WRF AND UKMET LATE WEDNESDAY INTO THURSDAY. WEDNESDAY NIGHT...TRIMMED TEMPS AND DEWPOINTS A FEW DEGREES AS WEAK SURFACE HIGH RESULTS IN EAST WIND FOR GENERALLY COMFORTABLE NIGHT. THURSDAY...WARM BUT NOT TOO HUMID AS SFC WINDS SLOWLY BECOME SE BY PM. POTENTIAL FOR MIN TEMPS STILL A FEW DEGREES TOO MILD IF THE CENTER OF SFC HIGH NEARBY FOR STRONGER RADIATIONAL COOLING. KEPT LOW CHANCE POPS THROUGH PERIOD NEAR IA/MO BORDER WITH FRONT NEARBY AND WEAK CONVERGENCE. THURSDAY NIGHT AND FRIDAY...WAA KICKS BACK IN WITH HIGHER DEWPOINTS AHEAD OF NEXT FRONT LATE FRIDAY WITH VERY WARM AND HUMID CONDITIONS AND BREEZY SW WINDS IN PM TO TAKE A BIT OFF THE HEAT OFF OF 85 TO 90+F MAX TEMPS. CONCERN IS POTENTIAL FOR STORMS TO FIRE LATE FRIDAY AND FRIDAY NIGHT WITH NEXT FRONTAL PASSAGE...LEFT DRY FOR NOW AND PASS FOR LATER SHIFTS TO CONSIDER. SATURDAY... ANOTHER WEAK FRONT TO PASS WITH EAST WINDS AND HAVE TRIMMED TEMPS WHICH STILL MAY BE AT LEAST A FEW DEGREES TOO HIGH INTO SUNDAY MORNING. SUNDAY...TEMPERATURES TO WARM BACK TO MID TO UPPER 80S TO POSSIBLY NEAR 90. MONDAY AND TUESDAY...LOTS OF MOISTURE FROM SOUTH PLAINS TO ARRIVE FROM TROPICAL SYSTEM MOVING NORTH AHEAD OF APPROACHING UPPER TROUGH AND HAVE UPPED CLOUDS AND LOWERED MAX TEMPS AND ALSO UPPER POPS TO 30 MON NIGHT. HIGH PW OF 1.5 TO 2 INCHES AND DECENT FORCING SUPPORT SEASONALLY HEAVY RAIN AMOUNTS FOR LATER SHIFTS TO MONITOR AND UPDATE ACCORDINGLY. MAX TEMPS A COMPROMISE...DEFINITELY HIGH TEMPS TO BE LOWER EARLY NEXT WEEK INTO REST OF NEXT WEEK. ..NICHOLS.. && .AVIATION... APPROACHING FRONTAL COMPLEX AND ASSOCIATED PRECIP WILL KNOCK DOWN CONDITIONS AT THE CID/MLI/DBQ TERMINAL SITES TO AT LEAST MVFR FROM 04Z TO 11Z OR SO...BEFORE WIND SHIFT TO THE NORTHWEST BRINGS BACK VFR CEILINGS AND VSBYS AFTER 14Z WED. && .DVN WATCHES/WARNINGS/ADVISORIES... IA...NONE. IL...NONE. MO...NONE. && 12/NICHOLS
HAZARDOUS WEATHER OUTLOOK NATIONAL WEATHER SERVICE QUAD CITIES IA IL 456 AM CDT TUE SEP 18 2007 IAZ040>042-051>054-063>068-076>078-087>089-098-099-ILZ001-002-007- 009-015>018-024>026-034-035-MOZ009-010-191000- BUCHANAN-DELAWARE-DUBUQUE-BENTON-LINN-JONES-JACKSON-IOWA-JOHNSON- CEDAR-CLINTON-MUSCATINE-SCOTT-KEOKUK-WASHINGTON-LOUISA-JEFFERSON- HENRY IA-DES MOINES-VAN BUREN-LEE-JO DAVIESS-STEPHENSON-CARROLL- WHITESIDE-ROCK ISLAND-HENRY IL-BUREAU-PUTNAM-MERCER-HENDERSON- WARREN-HANCOCK-MCDONOUGH-SCOTLAND-CLARK- 456 AM CDT TUE SEP 18 2007 THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF NORTH CENTRAL ILLINOIS...NORTHWEST ILLINOIS...WEST CENTRAL ILLINOIS...EAST CENTRAL IOWA...NORTHEAST IOWA...SOUTHEAST IOWA AND NORTHEAST MISSOURI. .DAY ONE...TODAY AND TONIGHT THUNDERSTORMS WILL MOVE INTO THE OUTLOOK AREA LATE THIS AFTERNOON AND EVENING AHEAD OF A COLD FRONT. THE STORM PREDICTION CENTER HAS PLACED A SLIGHT RISK OF SEVERE STORMS WEST OF A LINE FROM SIGOURNEY TO DUBUQUE IOWA. MODERATE INSTABILITY IS EXPECTED TO DEVELOP THIS AFTERNOON AS TEMPERATURES ONCE AGAIN RISE INTO THE MID 80S TO NEAR 90 TODAY...COMBINED WITH INCREASING HUMIDITY LEVELS. THE GREATEST RISK WITH THESE STORMS IS FOR DAMAGING WINDS AND HAIL. .DAYS TWO THROUGH SEVEN...WEDNESDAY THROUGH MONDAY THERE IS A CONTINUING CHANCE OF THUNDERSTORMS WEDNESDAY AND WEDNESDAY NIGHT. AT THIS TIME THESE STORMS ARE NOT EXPECTED TO PRODUCE SEVERE WEATHER. .SPOTTER INFORMATION STATEMENT... SPOTTER ACTIVATION IS POSSIBLE LATE THIS AFTERNOON AND EVENING NORTHWEST OF A LINE FROM SIGOURNEY TO DUBUQUE.
IAZ040-051-052-063-076-182350-
SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE QUAD CITIES IA IL
540 PM CDT TUE SEP 18 2007
THE NATIONAL WEATHER SERVICE IN THE QUAD CITIES HAS ISSUED A SPECIAL
WEATHER STATEMENT EFFECTIVE UNTIL 645 PM CDT FOR THE FOLLOWING
COUNTIES...
IN IOWA
BUCHANAN...BENTON...LINN...IOWA AND KEOKUK
INCLUDING...BUT NOT LIMITED TO THE FOLLOWING LOCATIONS
BELLE PLAINE...INDEPENDENCE...MARENGO...NORTH ENGLISH...
SIGOURNEY...STANLEY...URBANA...VAN HORNE...VINTON...
WHAT CHEER...WILLIAMSBURG AND WINTHROP
AT 532 PM CDT NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED
THUNDERSTORMS ALONG A LINE EXTENDING FROM 30 MILES NORTHWEST OF BELLE
PLAINE TO 43 MILES SOUTHWEST OF MARTINSBURG...OR ALONG A LINE
EXTENDING FROM 35 MILES SOUTHWEST OF WATERLOO TO 18 MILES NORTHWEST
OF LANCASTER...MOVING NORTHEAST AT 45 MPH.
ERVINThe Des Moines radar (KDMX), 122 km away, was scanning. The volume nearest the first event began at 23:13 UTC.
12 thunderstorm wind. Local standard time, as filed.
A wind gust was measured at 60 mph. Reported by the EMA office.
Winds were estimated to be 60 mph by the fire department at Van Horne, IA.
A wind gust of 79 mph was measured at Vinton, IA. Sustained winds were 46 mph.
Winds were estimated to be 65 mph about 7 miles southwest of Vinton, IA. Relayed by EM. Reported by a trained spotter.
Winds estimated to be 70 mph blew a 55,000 bushel grain bin over and a fertilizer storage bin 30 feet.
Winds were estimated to be 60 mph at the intersection of Highway 20 and Highway 150 at the Walmart Store in Independence, IA.
Winds estimated to be 65 mph blew down a large healthy oak tree near the intersection of 63rd Street and 28th Street in Vinton, IA.
Winds were estimated to be 65 mph near Troy Mills, IA.
A wind gust was measured at 62 mph in Edgewood, IA.
Winds estimated to be 65 mph blew down some trees in Manchester, IA.
Winds estimated to be 65 mph blew down some trees in Dundee, IA.
Winds estimated to be 65 mph blew down some trees and destroyed a 50 foot by 80 foot shop building in Edgewood, IA.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Iowa in 2007Every state in 2007This day in weather historyWarnings in Iowa, September 2007
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: 59248, 59249, 59250, 59251, 59252, 59253, 59254, 59255, 59256, 59257, 59258, 59259.