Heavy rains resulted in the flash flooding of Highway 61/27 about 3 miles southwest of Gregory Landing, MO during the predawn hours of August 17. The flood waters were flowing across the highway near the county line for a time.
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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.
Heavy rains resulted in the flash flooding of Highway 61/27 about 3 miles southwest of Gregory Landing, MO during the predawn hours of August 17. The flood waters were flowing across the highway near the county line for a time. Officers reported that the water had receded by 705 am.
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 17, 2:30 AM CST, 1 hour 30 minutes earlier.
AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE QUAD CITIES IA IL 330 AM CDT MON AUG 17 2009 .SYNOPSIS... VERY ACTIVE WEATHER ACROSS THE AREA THIS MORNING...WITH A FAIRLY LARGE BAND OF SHOWERS AND THUNDERSTORMS EXTENDING FROM NORTHEAST KANSAS...ACROSS NORTHERN MISSOURI AND SOUTHERN IOWA INTO NORTHWEST ILLINOIS. THIS CONVECTION IS BEING DRIVEN BY LOW LEVEL SOUTHERLY FLOW IMPINGING ON A VERY SLOW MOVING SURFACE AND 850MB BOUNDARY...EXTENDING FROM NEAR KANSAS CITY NORTHEAST TO CEDAR RAPIDS AND DUBUQUE AND OFF TO THE NORTHEAST IN WISCONSIN. IT HAS BEEN RATHER MUGGY EAST OF THAT BOUNDARY...WITH DEWPOINTS AROUND 70. A WEAK LITTLE SURFACE LOW IS MOVING NORTHEAST ALONG THAT BOUNDARY...AND IS CURRENTLY LOCATED NEAR KCDJ. A FEATURE OF INTEREST IS A SHORTWAVE ON IR SATELLITE OVER CENTRAL NEBRASKA...MOVING QUICKLY TO THE EAST. THERE IS CONVECTION OVER NEBRASKA AND KANSAS ASSOCIATED WITH THIS WAVE. ...LE... && .SHORT TERM...TODAY AND TONIGHT... THE CONVECTION CURRENTLY SHOWING OVER NORTHERN MISSOURI AND SOUTHERN IOWA SHOULD GRADUALLY SHIFT TO THE EAST-NORTHEAST...CONTINUING TO BE FED BY THE LOW LEVEL JET AND LIFT MOVING UP OVER THE BOUNDARY. THIS AFTERNOON THE SHORTWAVE COMING OUT OF NEBRASKA SHOULD GENERATE MORE SHOWERS AND THUNDERSTORMS ALONG THE BOUNDARY. MAIN RISK WITH ALL THIS IS HEAVY RAIN AND FLASH FLOODING...AS THE PRECIPITABLE WATER VALUES ARE UP AROUND 2 INCHES...AND 850MB DEWPOINTS ARE UP IN THE TEENS. SEVERE RISK IS RELATIVELY LOW WITH WET BULB ZERO VALUES ABOVE 13KFT AND WEAK INSTABILITY...MAKING IT DIFFICULT TO GET HAIL...THOUGH THERE MAY BE A DAMAGING WIND THREAT WITH A FEW OF THE STORMS. HAVE GONE WITH CATEGORICAL POPS ACROSS THE SOUTH HALF TO TWO THIRDS THIS MORNING...ALONG WITH A FLASH FLOOD WATCH DUE THE POTENTIAL FOR HEAVY RAINFALL. AS HAVE ALREADY ISSUED TWO FLASH FLOOD WARNINGS THIS MORNING...THIS SEEMS PRUDENT. MAX TEMPS WILL BE QUITE COOL TODAY WITH WARMEST TEMPS ACROSS THE SOUTH OF ONLY 80...THOUGH MUCH OF THE DAY WILL ONLY BE IN THE 70S. TONIGHT MUCH OF THE FORCING AND THE BOUNDARY SHIFT JUST FAR ENOUGH SOUTH THAT BY MID TO LATE EVENING THERE IS VERY LITTLE IF ANY RISK OF SHOWERS AND THUNDERSTORMS...AND WE MAY BE LOOKING AT A FOGGY NIGHT IF WE CAN CLEAR OUT ON THE NORTH SIDE OF THE CONVECTION THAT SHOULD BE ONGOING ACROSS MISSOURI. MIN TEMPS TONIGHT IN THE UPPER 50S AND 60S SHOULD FEEL LIKE A REAL IMPROVEMENT WITH DEWPOINTS DOWN IN THE 50S AND LOW 60S ONCE AGAIN. ...LE... .LONG TERM...TUESDAY THROUGH NEXT SUNDAY... 00Z MODELS HAVE CONFIRMED A SUSPICION REGARDING THE SLOW MOVING COLD FRONT. MODELS CONTINUE WITH SOME CONVERGENCE ACROSS THE SOUTH THIRD OF THE CWFA FOR MOST OF TUESDAY. SO...WILL ADD SCHC POPS FOR THAT AREA. INITIALLY THOUGHT TUESDAY NIGHT WOULD BE DRY. HOWEVER...TOOLS AND TECHNIQUES SUGGEST SOME WAA PRECIP MAY BREAK OUT ACROSS THE SOUTH THIRD OR SO PRIOR TO SUNRISE WEDNESDAY. THEREFORE...WILL GO DRY TUESDAY EVENING AND GO WITH SCHC/LOW CHC POPS OVER ABOUT THE SOUTHWEST THIRD OR SO LATE TUESDAY NIGHT. WEDNESDAY/WEDNESDAY NIGHT...WAA PRECIP OVERSPREADS THE CWFA ON WEDNESDAY. SOME AREAS MAY REMAIN DRY WEDNESDAY MORNING BUT THE ENTIRE AREA SHOULD SEE SOME PRECIP DURING THE AFTERNOON HOURS. WEDNESDAY NIGHT GETS REAL INTERESTING. YET ANOTHER SIGNIFICANT COLD FRONT MOVES INTO THE AREA. LLJ PUSHES 16C H85 DEW POINTS INTO THE AREA WITH GOOD CONVERGENCE. HAVE UPPED POPS FURTHER BUT CAT POPS FOR WED NIGHT LOOK JUSTIFIED. STRONG POTENTIAL FOR HEAVY RAIN AS WELL BUT HAVE LEFT THAT WORDING OUT FOR NOW. THURSDAY ON...NO CHANGES WERE MADE TO THE CURRENT FCST BASED ON CONCERNS CLOSER IN. 00Z GLOBAL MODELS INDICATE MERIDIONAL FLOW DEVELOPING AS A DEEP UPPER LOW SETTLES ACROSS THE GREAT LAKES. TEMPERATURES CURRENTLY LOOK TO BE ON THE WARM SIDE SO PASS THIS CONCERN ON. ...08... && .AVIATION... THUNDERSTORMS AND RAIN TO AFFECT KBRL AND KMLI FOR MUCH OF THE NEXT 12 HOURS...WITH MAINLY MVFR CIGS...THOUGH IFR CIGS AND VSBYS MAY ALSO BE EXPECTED WITH THE STRONGER STORMS. KCID AND KDBQ TO TO ALSO HAVE MVFR CIGS AND VSBYS WITH MORE SCATTERED SHOWERS AND THUNDERSTORMS...OTHERWISE VFR. AFTER 00Z THIS EVENING SHOWERS AND THUNDERSTORMS TO MOVE OFF TO THE SOUTHEAST...AND VFR CONDITIONS TO RETURN. ...LE... && .DVN WATCHES/WARNINGS/ADVISORIES... IA...FLASH FLOOD WATCH UNTIL 00Z THIS EVENING FOR DES MOINES-HENRY IA- JEFFERSON-LEE-VAN BUREN. IL...FLASH FLOOD WATCH UNTIL 00Z THIS EVENING FOR HANCOCK-HENDERSON- MCDONOUGH-WARREN. MO...FLASH FLOOD WATCH UNTIL 00Z THIS EVENING FOR CLARK-SCOTLAND. && LE/08
HAZARDOUS WEATHER OUTLOOK...CORRECTED NATIONAL WEATHER SERVICE QUAD CITIES IA IL 730 PM CDT SUN AUG 16 2009 IAZ040>042-051>054-063>068-076>078-087>089-098-099-ILZ001-002-007- 009-015>018-024>026-034-035-MOZ009-010-180030- 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- 730 PM CDT SUN AUG 16 2009 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...TONIGHT SHOWERS AND ISOLATED THUNDERSTORMS OCCURRING AHEAD OF A COLD FRONT FROM NEAR DUBUQUE THROUGH SIGOURNEY ARE EXPECTED TO WEAKEN AND DISSIPATE AFTER SUNSET. THUNDERSTORMS DEVELOPING OVER NORTHWEST MISSOURI ARE EXPECTED TO INCREASE IN COVERAGE AND SPREAD NORTHEAST INTO NORTHEAST MISSOURI...SOUTHEAST IOWA AND WEST CENTRAL ILLINOIS. SEVERE THUNDERSTORMS ARE NOT EXPECTED AT THIS TIME BUT LOCALLY HEAVY RAINS WILL BE POSSIBLE WITH THE STRONGER STORMS. .DAYS TWO THROUGH SEVEN...MONDAY THROUGH SATURDAY RAIN AND EMBEDDED THUNDERSTORMS WILL BECOME LIKELY ON MONDAY... ESPECIALLY SOUTH OF HIGHWAY 30. LOCALLY HEAVY RAIN IS POSSIBLE. THERE IS A CHANCE OF THUNDERSTORMS TUESDAY NIGHT THROUGH THURSDAY. HOWEVER...IT IS TOO EARLY TO DETERMINE THE SEVERE POTENTIAL AT THIS TIME. .SPOTTER INFORMATION STATEMENT... SPOTTER ACTIVATION IS NOT EXPECTED TONIGHT.
SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE QUAD CITIES IA IL
1134 PM CDT SUN AUG 16 2009
IAZ098-099-ILZ034-MOZ009-010-170630-
LEE IA-VAN BUREN IA-HANCOCK IL-CLARK MO-SCOTLAND MO-
1134 PM CDT SUN AUG 16 2009
...THUNDERSTORMS WITH HEAVY RAIN MAY CAUSE MINOR FLOODING...
THUNDERSTORMS WITH LOCALLY HEAVY RAINS CONTINUE TO MOVE OUT OF NORTH
CENTRAL MISSOURI...THROUGH SCOTLAND AND CLARK COUNTIES. DOPPLER
RADAR RAINFALL ESTIMATES INDICATED THAT PARTS OF SOUTHWEST SCOTLAND
COUNTY MAY HAVE RECEIVED 2 INCHES OR MORE OF RAIN SINCE 9 PM.
CONDITIONS WILL BE FAVORABLE THROUGH EARLY MONDAY MORNING FOR
ADDITIONAL THUNDERSTORMS TO MOVE THROUGH PARTS OF SCOTLAND AND CLARK
COUNTIES. THIS COULD RESULT IN PONDING OF WATER IN LOW LYING AREAS
AS WELL AS THE FLOODING OF SOME SMALL STREAMS.
&&
LAT...LON 4024 9150 4025 9151 4027 9196 4030 9196
4030 9234 4060 9235 4060 9220 4062 9220
4075 9139 4022 9127
DLFPRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE QUAD CITIES IA IL
1208 AM CDT MON AUG 17 2009
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE....
..REMARKS..
1201 AM HEAVY RAIN 4 SW GRANGER 40.43N 92.02W
08/17/2009 M1.30 INCH SCOTLAND MO TRAINED SPOTTER
SINCE 7 PM.
&&
LEThe Quad Cities radar (KDVN), 170 km away, was scanning. The volume nearest the first event began at 10:00 UTC.
1 flash flood. Local standard time, as filed.
Heavy rains resulted in the flash flooding of Highway 61/27 about 3 miles southwest of Gregory Landing, MO during the predawn hours of August 17. The flood waters were flowing across the highway near the county line for a time. Officers reported that the water had receded by 705 am.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Missouri in 2009Every state in 2009This day in weather historyWarnings in Missouri, August 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: 192122.