Thunderstorms with heavy rains, produced flash flooding on August 16, 2009.
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 EAX wrote it up.
Thunderstorms with heavy rains, produced flash flooding on August 16, 2009.
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 Kansas City, MO wrote its last area forecast discussion before the first event at Aug 16, 5:54 AM CST, 4 hours earlier.
AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE KANSAS CITY/PLEASANT HILL MO 654 AM CDT SUN AUG 16 2009 ...UPDATED AVIATION DISCUSSION... .DISCUSSION... THE COLD FRONT MADE FAIRLY STEADY PROGRESS THROUGH THE FIRST HALF OF THE OVERNIGHT HOURS...AIDED BY MODERATE TO STRONG CONVECTION. HOWEVER THAT CONVECTION IS NOW IN A WEAKENING PHASE...AS THE SHORTWAVE ENERGY WHICH INITIATED IT MOVES OFF TO THE NORTHEAST. THAT BEING SAID...EXPECT COLD POOL FROM SAID CONVECTION AND THEREFORE THE EFFECTIVE COLD FRONT TO CONTINUE TO MOVE SOUTHEAST INTO NORTHWEST MISSOURI AND NORTHEAST KANSAS THROUGH THE MORNING. THE SOUTHEASTWARD PROGRESS IS EXPECTED TO SLOW CONSIDERABLY BY MID TO LATE MORNING...AS THE SHORTWAVE ENERGY CONTINUES TO MOVE OFF TO THE NORTHEAST AND THE MID LEVEL RIDGE HOLDS TIGHT OVER THE SOUTHERN US. EXPECT LINGERING SURFACE BOUNDARY TO BE DRAPED OVER NORTHWEST MISSOURI THROUGH THE REST OF THE DAY...POSSIBLY AS FAR SOUTH AS A STJ/MCI TO IRK LINE. MEANWHILE AREA OF CONVECTION CURRENTLY OVER MUCH OF NORTHERN MISSOURI WILL CONTINUE TO MOVE NORTHEAST...WITH ADDITIONAL CONVECTION BECOMING INCREASINGLY ELEVATED UNDER MID LEVEL MOISTURE PLUME AND BROAD ISENTROPIC LIFT REGIME. AS LOW LEVEL JET WEAKENS CONSIDERABLY DURING THE MORNING...THIS CONVECTION IS EXPECTED TO DIMINISH. WHILE LEAD SHORTWAVE WILL MOVE OFF TO THE NORTHEAST AND LOW LEVEL JET WEAKENS DURING THE DAY...BROAD ISENTROPIC LIFT WILL CONTINUE WITHIN MOISTURE PLUME. IN ADDITION...ANY EMBEDDED SHORTWAVES WITHIN IT WILL SPARK SCATTERED SHOWERS AND THUNDERSTORMS. THE AMOUNT OF INSTABILITY IS THEREFORE IN QUESTION. DESTABILIZATION MOST LIKELY OVER CENTRAL INTO EASTERN KANSAS THIS AFTERNOON...AS THE UPPER TROUGH AXIS APPROACHES. THIS ACTIVITY WOULD THEN DEVELOP NORTHEAST ALONG THE SURFACE BOUNDARY INTO NORTHERN MISSOURI. 2000-3000 J/KG CAPE POSSIBLE ALONG THE SURFACE BOUNDARY. SHEAR IS NOT EXPECTED TO BE STRONG DURING THE LATE AFTERNOON HOURS...HOWEVER MODELS SUGGEST IT WILL INCREASE DURING THE EVENING. ALTHOUGH INSTABILITY WILL BE DECREASING AT THAT TIME. THEREFORE LARGE HAIL AND STRONG WINDS WILL BE THE PRIMARY THREATS. PWAT REMAINS HIGH SO ANY STORM WHICH FORMS MAY BRING LOCALLY HEAVY RAINFALL. THE SURFACE BOUNDARY WILL STILL BE DRAPED ACROSS THE REGION ON MONDAY. THEREFORE MANY OF THE SAME CONCERNS ABOUT LOCATION OF HEAVY RAIN AND POSSIBLE SEVERE STORMS PERSIST INTO MONDAY. FOR NOW HAVE INCREASED POPS ACROSS THE BOARD. && .AVIATION... FOR THE 12Z TAFS...WITH ONGOING CONVECTIVE ACTIVITY ACROSS THE TERMINALS CEILING HEIGHTS AND WINDS WILL BE DIFFICULT TO PIN DOWN THROUGH THE MORNING HOURS. CIGS HAVE ALREADY BEEN WONDERING IN AND OUT OF THE MVFR AND VFR CATEGORIES. AFTERNOON HOURS WILL NOT BE MUCH BETTER AS EXPECTATIONS ARE THAT MORE THUNDERSTORM ACTIVITY WILL DEVELOP OVER THE KANSAS MISSOURI BORDER REGION AGAIN LATER THIS AFTERNOON. THEREFORE...OVERALL CONFIDENCE IN THE FORECAST IS LOW...AND MANY AMENDMENTS WILL LIKELY BE NEEDED FOR THE TAFS TODAY. ONGOING MORNING CONVECTION IS EXPECTED TO PERSIST THROUGH AROUND 15Z...WHICH IS WHEN CURRENT TIMING WOULD HAVE THE BACK EDGE OF THE CONVECTION SHIFTING EAST OF THE TERMINALS. HOWEVER...ACTIVITY FARTHER TO THE WEST...LIFTING NORTHEAST...MAY STILL DRAG ITS FOOT ACROSS THE TERMINALS...SO HAVE LEFT VCSH WITH A CB IN THE CLOUD GROUP THROUGH THE LATE MORNING AND AFTERNOON HOURS. ADDED A TEMPO GROUP FOR THE LATE AFTERNOON EARLY EVENING HOURS AS A COLD FRONT SLOWLY SHIFTS SOUTHEAST THROUGH THE REGION...WHICH WITH THE AFTERNOON SUN...MAY SPARK MORE WIDESPREAD THUNDERSTORMS ACTIVITY. GONE WITH A PROB30 GROUP FOR THE POST 00Z HOURS OF THE EVENING WHEN SUNS HEATING WILL BE LESS HELPFUL AND CURRENT MODEL OUTPUT INDICATES PRECIPITATION MAY BE SHIFTING SOUTH AND EAST. CUTTER && .EAX WATCHES/WARNINGS/ADVISORIES... MO...NONE. KS...NONE.
HAZARDOUS WEATHER OUTLOOK NATIONAL WEATHER SERVICE KANSAS CITY/PLEASANT HILL MO 556 AM CDT SUN AUG 16 2009 KSZ025-057-060-102>105-MOZ001>008-011>017-020>025-028>033-037>040- 043>046-053-054-171100- ATCHISON KS-MIAMI-LINN KS-DONIPHAN-LEAVENWORTH-WYANDOTTE- JOHNSON KS-ATCHISON MO-NODAWAY-WORTH-GENTRY-HARRISON-MERCER- PUTNAM-SCHUYLER-HOLT-ANDREW-DE KALB-DAVIESS-GRUNDY-SULLIVAN-ADAIR- BUCHANAN-CLINTON-CALDWELL-LIVINGSTON-LINN MO-MACON-PLATTE-CLAY- RAY-CARROLL-CHARITON-RANDOLPH-JACKSON-LAFAYETTE-SALINE-HOWARD- CASS-JOHNSON MO-PETTIS-COOPER-BATES-HENRY- 556 AM CDT SUN AUG 16 2009 THIS HAZARDOUS WEATHER OUTLOOK IS FOR NORTHWEST...NORTH CENTRAL AND WEST CENTRAL MISSOURI...AS WELL AS EXTREME EASTERN KANSAS. .DAY ONE...TODAY AND TONIGHT WIDESPREAD SHOWERS AND THUNDERSTORMS WILL GRADUALLY DIMINISH THROUGH THE MORNING HOURS. THIS ACTIVITY IS NOT EXPECTED TO BECOME SEVERE. A SURFACE BOUNDARY WILL THEN LINGER OVER NORTHERN MISSOURI THROUGH THE REST OF THE DAY AND INTO TONIGHT. ANOTHER ROUND OF THUNDERSTORMS IS EXPECTED TO DEVELOP ALONG THIS BOUNDARY DURING THE AFTERNOON AND EVENING HOURS...AFFECTING AREAS MAINLY ALONG AND NORTH OF A LINE FROM KANSAS CITY TO MACON. THESE THUNDERSTORMS WILL PRESS GENERALLY EASTWARD DURING THE EVENING AND OVERNIGHT HOURS. THE AMOUNT OF INSTABILITY WILL DEPEND ON THE AMOUNT OF DAYTIME HEATING. IF SUFFICIENT HEATING OCCURS...SOME OF THE STORMS MAY BE STRONG TO SEVERE. THE PRIMARY THREATS WITH NAY SEVERE STORMS WILL BE LARGE HAIL...DAMAGING WIND AND HEAVY RAIN. AN ISOLATED TORNADO MAY BE POSSIBLE...BUT THE PROBABILITIES REMAIN VERY LOW. .DAYS TWO THROUGH SEVEN...MONDAY THROUGH SATURDAY THE FRONT IS EXPECTED TO LINGER OVER THE MIDWEST REGION THROUGHOUT THE FIRST HALF OF NEXT WEEK...BRINGING PERIODIC CHANCES OF RAIN. THE NEXT HIGHEST CHANCE OF THUNDERSTORMS WILL ARRIVE ON MONDAY...WITH AN ATTENDANT THREAT FOR SEVERE STORMS WITH LARGE HAIL AND DAMAGING WINDS. A BRIEF BREAK FROM THE RAIN MAY ARRIVE FOR MONDAY NIGHT INTO TUESDAY AS THE FRONT TEMPORARILY SINKS SOUTH...BEFORE THE NEXT GOOD CHANCE FOR RAIN ARRIVES FOR THE MIDDLE OF THE WEEK. THERE IS TOO MUCH UNCERTAINTY IN THE FORECAST DETAILS TOWARD MID-WEEK...TO DETERMINE A SEVERE THREAT FOR THAT TIME FRAME. OF MORE CERTAINTY IS A THREAT FOR LOCALLY HEAVY RAIN IN ANY STORM WHICH MOVES OVERHEAD...DUE TO THE ABUNDANT ATMOSPHERIC MOISTURE ACROSS THE REGION. .SPOTTER INFORMATION STATEMENT... SPOTTER ACTIVATION MAY BE NEEDED THIS AFTERNOON AND EVENING AND AGAIN MONDAY AFTERNOON.
PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE KANSAS CITY/PLEASANT HILL MO
951 AM CDT SUN AUG 16 2009
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE....
..REMARKS..
0941 AM FLASH FLOOD E OSBORN 39.75N 94.36W
08/16/2009 DEKALB MO LAW ENFORCEMENT
WATER WAS REPORTED FLOWING OVER HIGHWAY 36, A QUARTER
MILE EAST OF OSBORN.
&&
GAMISPRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE KANSAS CITY/PLEASANT HILL MO
952 AM CDT SUN AUG 16 2009
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE....
..REMARKS..
0941 AM FLASH FLOOD FAIRPORT 39.98N 94.35W
08/16/2009 DEKALB MO LAW ENFORCEMENT
WATER WAS REPORTED FLOWING OVER HIGHWAY A, OVER THE NORTH
SIDE OF FAIRPORT.
&&
GAMISThe Pleasant Hill radar (KEAX), 92 km away, was scanning. The volume nearest the first event began at 15:55 UTC.
1 flash flood. Local standard time, as filed.
Water was reported flowing over Highway A in Turney. One vehicle accident was reported with this flooding.
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: 190587.