A line of showers and thunderstorms moved across eastern Iowa during the early morning hours of September 1. A tree was blown down in Mount Pleasant, IA.
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.
A line of showers and thunderstorms moved across eastern Iowa during the early morning hours of September 1. A tree was blown down in Mount Pleasant, IA.
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 Aug 31, 2:05 PM CST, 9 hours 55 minutes earlier.
AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE QUAD CITIES IA IL 305 PM CDT TUE AUG 31 2010 .SYNOPSIS... GRADUALLY WEAKENING SCATTERED SHOWERS AND ISOLATED THUNDERSTORMS ARE CONTINUING TO SHIFT EAST ACROSS THE FORECAST AREA. THOUGH THE INDIVIDUAL FEATURE MOVEMENT IS TO THE NORTHEAST...THE WHOLE THING IS GRADUALLY SHIFTING EAST. IT HAS SLOWED DOWN OVER THE PAST SEVERAL HOURS ALONG WITH THE WEAKENING TREND. A COLD FRONT IS DRAPED FROM NORTHEAST MINNESOTA...SOUTHWEST ACROSS THE NORTHWEST CORNER OF IOWA AND INTO NEBRASKA AND KANSAS THIS AFTERNOON. AHEAD OF THIS COLD FRONT DEWPOINTS ARE SITTING IN THE LOW 70S...WITH TEMPERATURES WELL UP INTO THE 80S FOR MOST OF IOWA. THE SATELLITE IMAGERY SHOWS THAT SOUTHEAST NEBRASKA AND WESTERN IOWA HAVE CLEARED OUT AHEAD OF THE COLD FRONT...AND NEW CONVECTION HAS FIRED NEAR THE BOUNDARY IN NORTHERN AND NORTHWESTERN IOWA. EXPECT MORE CONVECTION TO FIRE BACK WEST INTO NEBRASKA...THOUGH THE CAP MAY BE A LIMITING FACTOR THERE. UPPER LEVEL ANALYSIS SHOWS A GOOD DEEP MOISTURE PLUME EXTENDING FROM THE GULF UP ACROSS THE MIDWEST...ALONG WITH A THERMAL RIDGE JUST TO ITS WEST. THERE IS ALSO AN INTERESTING LITTLE SHORTWAVE JUST NOW MOVING ACROSS NEBRASKA...WHICH MAY BE A FACTOR IN THE NEXT FEW HOURS OUT THERE. STRONGLY AMPLIFIED PATTERN AT THE UPPER LEVELS ALONG WITH AN UPPER LEVEL JET WHICH EXTENDS FROM ARIZONA TO NORTH DAKOTA. ..LE.. && .SHORT TERM...TONIGHT AND WEDNESDAY... THE CURRENT BAND OF SHOWERS AND THUNDERSTORMS SHOULD REALLY DIMINISH IN THE NEXT FEW HOURS...BUT HAVE LEFT SOME EVENING POPS ACROSS THE EASTERN CWA TO ACCOUNT FOR THEIR POSSIBLE PRESENCE. THERE IS A LITTLE INSTABILITY...BUT NO SHEAR AND THEY ARE GETTING AWAY FROM THE MID LEVEL CONVERGENCE AS WELL...SO THEY SHOULD FALL APART. HOWEVER...THE NEW CONVECTION NOW FIRING OUT OVER NORTHWEST IOWA AND LIKELY ZIPPERING BACK SOUTHWEST INTO NEBRASKA SHOULD BE THE BASIS FOR AN MCS TONIGHT...THAT SHOULD MOVE EAST TO AFFECT THE FORECAST AREA OVERNIGHT TONIGHT. CORFIDI VECTORS SHOW A NORTHEAST MOVEMENT...SIMILAR TO THE CURRENT SHOWER AND THUNDERSTORM BAND. WE REMAIN IN THE EASTERN EDGE OF THE SLIGHT RISK OUTLOOK FROM SPC FOR TONIGHT...BUT THIS RISK IS QUITE SMALL WITH VERY LITTLE/WEAK SHEAR AND THE BEST INSTABILITY REMAINING TO THE WEST WITH LITTLE HEATING HAVING TAKEN PLACE OVER OUR AREA TODAY. MIN TEMPS TONIGHT SHOULD BE SLIGHTLY COOLER THAN THIS MORNINGS WITH RAINFALL IN THE AREA TO HELP BRING IT DOWN...BUT DEWPOINTS REMAINING HIGH TO KEEP THEM FROM FALLING OFF VERY FAR. WEDNESDAY THE MCS SHOULD CONTINUE TO DROP SLOWLY ACROSS THE REMAINDER OF THE AREA ALONG WITH THE COLD FRONT...WITH THE STRONGEST ACTIVITY ACROSS OUR SOUTHERN CWA WHERE SOME NEW REGENERATION MAY OCCUR ON THE SOUTHWEST FLANK OF THE MCS. THE COLD FRONT WILL BE DRAPED ACROSS OUR SOUTHEAST CWA BY LATE AFTERNOON...WHICH MAY SERVE AS A FOCUS FOR MORE CONVECTION DURING THE AFTERNOON HOURS. IT ALL WILL DEPEND ON WHAT OUTFLOW BOUNDARIES GET SENT OUT BY THE OVERNIGHT MCS. TEMPERATURES WILL BE COOL FOR THE NORTHERN CWA WITH NORTH FLOW AND A SURFACE RIDGE BUILDING IN. HOWEVER WE ARE REALLY NOT LOOKING AT A VERY LARGE AIRMASS CHANGE AND HAVE KEPT MAX TEMPS IN THE LOW 80S FOR MOST OF THE AREA. ..LE.. .LONG TERM...WEDNESDAY NIGHT THROUGH NEXT TUESDAY...WARM...HUMID AND UNSETTLED CONDITIONS CONTINUE UNTIL MAIN COLD FRONTAL PASSAGE LATE THURSDAY. COOLER...FALL LIKE TEMPERATURES THEN FOLLOW FRI INTO SAT. BEYOND...WARMER TEMPERATURES RETURN EARLY NEXT WEEK AS UPPER FLOW BECOMES LESS AMPLIFIED AND MORE ZONAL. WED NIGHT...FOCUSING MECHANISMS FOR MCS DEVELOPMENT LOOKING LESS CLEAR CUT OVER THE AREA. ONE AXIS FOR THUNDERSTORM DEVELOPMENT WILL BE ALONG A REDEVELOPING WARM FRONT WELL NORTH OF THE AREA ACROSS MN AND WI AND THE OTHER ALONG A WEAKER BOUNDARY THAT WILL BE ALONG OR JUST SOUTH OR SOUTHEAST OF THE SOUTHERN CWA BORDER. WILL CERTAINLY BE PLENTY OF MOISTURE TO WORK WITH AS AREA REMAINS IN HIGH PW AIRMASS...ALTHOUGH LAPSE RATES AND SHEAR VALUES RATHER UNIMPRESSIVE. WILL CONTINUE TO BROADBRUSH WITH LOW END LIKELY CATEGORY POPS THROUGH THE NIGHT WITH HIGH DEWPOINTS AND CLOUDS HOLDING MINS WELL ABOVE NORMAL IN THE MID 60S AROUND 70. AS SOMEWHAT EXPECTED...LATEST MODELS HAVE SLOWED THURSDAY/S COLD FRONT SOME...NOW DEPICTING IT PUSHING THROUGH DURING THE PRIME MID TO LATE AFTERNOON HOURS. WITH MORE FAVORABLE SHEAR...AT LEAST MODERATELY STRONG MID LEVEL FORCING FROM A STRONG UPPER LEVEL SHORTWAVE...AND POTENTIAL FOR AT LEAST MODEST LOW LEVEL INSTABILITY IN THE FORM OF 2000 J/KG PLUS CAPES AHEAD OF THE FRONT...THIS LOOKS TO BE THE MOST FAVORABLE PERIOD FOR WIDESPREAD THUNDERSTORM COVERAGE AND DESERVING OF THE GREATEST THUNDERSTORM CHANCES. CURRENT INDICATIONS WOULD SUGGEST A POTENTIAL FOR SEVERE STORMS WITH PRIMARILY A DAMAGING WIND THREAT ALONG AND AHEAD OF THE FRONT IN THE AFTERNOON INTO EARLY EVENING. BASED ON RECENT TRENDS IN THIS AIRMASS...WILL COUNT ON CLOUD COVER TO HOLD HIGHS NEARER TO THE LOW END OF THE UNUSUALLY LARGE GUIDANCE SPREAD...IN THE UPPER 70S TO LOWER 80S. FRIDAY...40 KT PLUS NW WINDS AT H8 ARE DEPICTED PULLING DOWN TEMPERATURES AS LOW AS 6 TO 8 DEG C OVER THE NORTH BY FRI EVENING. EVEN WITH DEEP MIXING...THIS WOULD LIMIT HIGHS TO A RANGE OF THE UPPER 60S NORTHEAST TO MID 70S FAR SOUTH. WEAK PRESSURE GRADIENT AND AT LEAST LIGHT NW WINDS SHOULD PREVENT MINS FROM DIPPING BELOW THE 50S IN MOST SPOTS FRI NIGHT UNDER MOSTLY CLEAR SKIES. THE SURFACE RIDGE AXIS THAT FOLLOWS PASSES OVER THE AREA SATURDAY. WILL COUNT ON NEAR FULL SUNSHINE TO RETURN HIGHS TO THE LOWER TO MID 70S. WESTERN UPPER RIDGE FLATTENS AND PASSES OVER THE AREA SUN INTO EARLY NEXT WEAK RETURNING A MORE ZONAL FLOW OVERHEAD. THIS WILL ALLOW A GRADUAL WARMING TREND WITH TEMPERATURES RETURNING TO ABOVE NORMAL. GULF MOISTURE RETURN AND ONSET OF WEAK IMPULSES IN THE WESTERLIES WILL INCREASE RAIN CHANCES TOWARD MID WEEK...BUT WILL NOT GO ABOVE SLIGHT CHANCES IN THE MON NIGHT THROUGH TUE TIMEFRAME FOR NOW. ..SHEETS.. && .AVIATION... MAINLY MVFR ACROSS THE AREA THIS AFTERNOON WITH A FEW IFR CIGS IN -TSRA...MAINLY AFFECTING KCID AND KDBQ THROUGH APPROX 00Z THIS EVENING. WE SHOULD RETURN TO VFR BEFORE THE NEXT WAVE OF THUNDERSTORMS MOVES IN AFTER 03Z...WITH IFR VSBYS AND IFR TO LOW END MVFR CIGS DURING THE OVERNIGHT TIME FRAME. VSBYS SHOULD IMPROVE TO AT LEAST MVFR AFTER 11Z...BUT MVFR LOW CLOUDS SHOULD LINGER IN THE MORNING BEFORE CLEARING OUT SOME IN THE LATE MORNING AND AFTERNOON HOURS. ..LE.. .DVN WATCHES/WARNINGS/ADVISORIES... IA...NONE. IL...NONE. MO...NONE. && LE/SHEETS
HAZARDOUS WEATHER OUTLOOK NATIONAL WEATHER SERVICE QUAD CITIES IA IL 431 AM CDT TUE AUG 31 2010 IAZ040>042-051>054-063>068-076>078-087>089-098-099-ILZ001-002-007- 009-015>018-024>026-034-035-MOZ009-010-010945- 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- 431 AM CDT TUE AUG 31 2010 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 SCATTERED SHOWERS AND THUNDERSTORMS WILL MOVE THROUGH THE AREA TODAY...WITH NO SEVERE WEATHER EXPECTED. THE STORM PREDICTION CENTER HAS A SLIGHT RISK FOR SEVERE THUNDERSTORMS FOR EASTERN IOWA TONIGHT...AS STRONGER STORMS THIS EVENING COULD PRODUCE DAMAGING WINDS. OTHERWISE THE MAIN THREAT FOR STORMS TONIGHT WILL BE LOCALLY HEAVY RAINFALL. THOUGH HEAVY IN SPOTS...THE RECENT DRY WEATHER SHOULD ALLOW FOR THE RAIN TO BE ABSORBED. .DAYS TWO THROUGH SEVEN...WEDNESDAY THROUGH MONDAY THUNDERSTORMS WILL BE LIKELY WEDNESDAY THROUGH THURSDAY. LOCALLY HEAVY RAINFALL IS EXPECTED BUT THE RISK FOR SEVERE WEATHER IS VERY LOW. .SPOTTER INFORMATION STATEMENT... SPOTTER ACTIVATION IS POSSIBLE THIS EVENING OVER EASTERN IOWA. ERVIN/HAASE
SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE QUAD CITIES IA IL
1041 PM CDT TUE AUG 31 2010
IAZ040>042-052>054-064>066-010445-
BUCHANAN-CEDAR-CLINTON-DELAWARE-DUBUQUE-JACKSON-JOHNSON-JONES-LINN-
1041 PM CDT TUE AUG 31 2010
...STRONG THUNDERSTORMS WITH VERY HEAVY RAIN AND GUSTY WINDS...
AT 1036 PM CDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED
STRONG THUNDERSTORMS ALONG A LINE EXTENDING FROM COLESBURG TO 17
MILES SOUTHWEST OF SOLON...MOVING EAST AT 30 MPH.
* THUNDERSTORMS WILL BE NEAR...
LUXEMBURG...VIOLA...STONE CITY AND SOLON AROUND 1045 PM CDT...
HOLY CROSS...WORTHINGTON...MONTICELLO AND LISBON AROUND 1050 PM
CDT...
RICKARDSVILLE AND MORLEY AROUND 1055 PM CDT...
STRONG GUSTY WINDS OF 30 TO 40 MPH CAN BE EXPECTED WITH THIS LINE OF
STORMS. IN ADDITION... VERY HEAVY RAIN WILL OCCUR WITH RAINFALL
AMOUNTS OF AN INCH IN LESS THAN 30 MINUTES LIKELY. THIS WILL CAUSE
PONDING OF WATER ON ROADS AND IN LOW-LYING AREAS.
SEEK SHELTER IN A STURDY STRUCTURE UNTIL THIS STORM HAS PASSED.
A SEVERE THUNDERSTORM WATCH REMAINS IN EFFECT UNTIL 100 AM CDT
WEDNESDAY MORNING FOR NORTHEASTERN IOWA.
LAT...LON 4265 9072 4262 9068 4180 9067 4178 9161
4265 9163 4265 9091 4269 9089
TIME...MOT...LOC 0339Z 273DEG 25KT 4257 9119 4165 9171PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE QUAD CITIES IA IL
1054 PM CDT TUE AUG 31 2010
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE....
..REMARKS..
1049 PM TSTM WND GST SW CEDAR RAPIDS 41.97N 91.67W
08/31/2010 E50 MPH LINN IA TRAINED SPOTTER
WINDS ESTIMATED 40 TO 50 MPH.
1049 PM HAIL SW CEDAR RAPIDS 41.97N 91.67W
08/31/2010 E0.25 INCH LINN IA TRAINED SPOTTER
1039 PM TSTM WND GST CEDAR RAPIDS 41.97N 91.67W
08/31/2010 E55 MPH LINN IA TRAINED SPOTTER
&&PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE QUAD CITIES IA IL
1058 PM CDT TUE AUG 31 2010
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE....
..REMARKS..
1057 PM HEAVY RAIN 1 SSE CEDAR RAPIDS 41.95N 91.66W
08/31/2010 M1.00 INCH LINN IA TRAINED SPOTTER
ONE INCH OF RAIN IN PAST 15 MINUTES.
&&
HAASESPECIAL WEATHER STATEMENT NATIONAL WEATHER SERVICE QUAD CITIES IA IL 1101 PM CDT TUE AUG 31 2010 IAZ041-042-052>054-064>068-ILZ001-010500- CEDAR-CLINTON-DELAWARE-DUBUQUE-JACKSON-JO DAVIESS-JOHNSON-JONES-LINN-MUSCATINE-SCOTT- 1101 PM CDT TUE AUG 31 2010 ...STRONG WINDS AND VERY HEAVY RAIN WITH LINE OF STORMS... AT 1055 PM CDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED STRONG THUNDERSTORMS ALONG A LINE EXTENDING FROM MONTICELLO TO 7 MILES SOUTHWEST OF UNIVERSITY HEIGHTS...MOVING EAST AT 40 MPH. * THUNDERSTORMS WILL BE NEAR... OLIN...MECHANICSVILLE AND CENTER JUNCTION AROUND 1105 PM CDT... WYOMING...STANWOOD AND ONSLOW AROUND 1110 PM CDT... CANTON AND LOST NATION AROUND 1115 PM CDT... TIPTON...OXFORD JUNCTION AND MONMOUTH AROUND 1120 PM CDT... DIXON...DEWITT AND MAQUOKETA AROUND 1145 PM CDT... STRONG GUSTY WINDS OF 30 TO 55 MPH CAN BE EXPECTED WITH THIS LINE OF STORMS. THESE WINDS MAY CAUSE SMALL BRANCHES TO BE BLOWN DOWN...AND LOOSE OBJECTS TO BLOW AROUND. IN ADDITION... VERY HEAVY RAIN WILL OCCUR WITH RAINFALL AMOUNTS OF AN INCH IN LESS THAN 30 MINUTES LIKELY. THIS WILL CAUSE PONDING OF WATER ON ROADS AND IN LOW-LYING AREAS. PEA SIZE WILL ALSO BE POSSIBLE. SEEK SHELTER IN A STURDY STRUCTURE UNTIL THIS STORM HAS PASSED. A SEVERE THUNDERSTORM WATCH REMAINS IN EFFECT UNTIL 100 AM CDT WEDNESDAY MORNING FOR NORTHEASTERN IOWA. LAT...LON 4230 9041 4158 9058 4158 9168 4230 9146 TIME...MOT...LOC 0358Z 278DEG 38KT 4224 9107 4159 9162
PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE QUAD CITIES IA IL
1116 PM CDT TUE AUG 31 2010
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE....
..REMARKS..
1115 PM HEAVY RAIN 1 SSE CEDAR RAPIDS 41.95N 91.66W
08/31/2010 M1.35 INCH LINN IA TRAINED SPOTTER
PAST 30 MINUTES. RAINING LIGHTLY. DAILY TOTAL 2.07 INCHES
SO FAR. PONDING OF WATER ON STREETS.
&&SPECIAL WEATHER STATEMENT NATIONAL WEATHER SERVICE QUAD CITIES IA IL 1147 PM CDT TUE AUG 31 2010 IAZ042-054-065>068-076>078-087>089-098-099-ILZ001-002-007-009-015- 016-024-010700- DUBUQUE-JACKSON-CEDAR-CLINTON-MUSCATINE-SCOTT-KEOKUK-WASHINGTON- LOUISA-JEFFERSON-HENRY IA-DES MOINES-VAN BUREN-LEE-JO DAVIESS- STEPHENSON-CARROLL-WHITESIDE-ROCK ISLAND-HENRY IL-MERCER- INCLUDING THE CITIES OF...DUBUQUE...MAQUOKETA...TIPTON... CLINTON...MUSCATINE...BETTENDORF...DAVENPORT...SIGOURNEY... WASHINGTON...WAPELLO...FAIRFIELD...MOUNT PLEASANT...BURLINGTON... KEOSAUQUA....FORT MADISON...GALENA...FREEPORT...MOUNT CARROLL... STERLING...ROCK FALLS...MOLINE...ROCK ISLAND...KEWANEE...ALEDO 1147 PM CDT TUE AUG 31 2010 ...STRONG GUSTY WINDS AND VERY HEAVY RAIN WITH LINE OF STORMS... AT 1145 PM CDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED THE LEADING EDGE OF A LINE OF STRONG THUNDERSTORMS EXTENDING FROM JUST EAST OF DUBUQUE...TO NEAR DEWITT...MUSCATINE...WASHINGTON AND SIGOURNEY... MOVING EAST AT 35 MPH. STRONG GUSTY WINDS OF 30 TO 50 MPH CAN BE EXPECTED WITH THIS LINE OF STORMS...AS THEY CONTINUE MOVING EAST OVER THE NEXT COUPLE OF HOURS. THESE WINDS WILL LIKELY ARRIVE AHEAD OF THE RAIN... AND MAY CAUSE SMALL BRANCHES TO BE BLOWN DOWN...AND LOOSE OBJECTS TO BLOW AROUND. IN ADDITION... VERY HEAVY RAIN WILL OCCUR WITH RAINFALL AMOUNTS OF AN INCH IN LESS THAN 30 MINUTES LIKELY. THIS WILL CAUSE PONDING OF WATER ON ROADS AND IN LOW-LYING AREAS. PEA SIZE HAIL WILL ALSO BE POSSIBLE.
The Quad Cities radar (KDVN), 110 km away, was scanning. The volume nearest the first event began at 06:01 UTC.
1 thunderstorm wind. Local standard time, as filed.
Wind gusts estimated to be 60 mph blew a tree down on the west side of Mount Pleasant, IA around 1 am CDT September 1. In addition, some vendor tents in front of Warner Engineering were also blown over.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Iowa in 2010Every state in 2010This day in weather historyWarnings in Iowa, September 2010
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: 259766.