Isolated severe thunderstorms were observed, during the early morning hours, of July 11, 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.
Isolated severe thunderstorms were observed, during the early morning hours, of July 11, 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 Jul 10, 11:46 PM CST, 2 hours 24 minutes earlier.
AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE KANSAS CITY/PLEASANT HILL MO 1246 AM CDT SAT JUL 11 2009 .DISCUSSION... SHOWERS CONTINUE TO PERCOLATE ALONG AN AXIS FROM NERN KANSAS THROUGH CNTRL MISSOURI IN ASSOCIATION WITH WEAK LIFT ALONG THE 316K-318K ISENTROPES. BOTH THE NAM-WRF AND RUC APPEAR TO CAPTURE THIS PHENOMENA THE BEST...KEEPING SCT SHRA GOING FOR THE NEXT COUPLE HOURS...BEFORE LIFTING REGIME REALIGNS FURTHER TO THE SOUTH. WHILE A LIGHTNING STRIKE IS STILL POSSIBLE FEEL ACTIVITY WILL BE MOSTLY PLAIN SHRA...AND HAVE ADJUSTED FORECAST TO BEST ALIGN POPS AND WX MENTION THIS EVENING. STILL SIGNIFICANT UNCERTAINTY REGARDING ADDITIONAL CONVECTIVE DEVELOPMENT OVERNIGHT. BASED ON ISENTROPIC ANALYSIS/FORECASTS THROUGH THE 314K-318K LAYER (SUPERIOR DISCRIMINATOR FOR CONVECTION THE PAST 2 NIGHTS)...FEEL MOST CONFIDENT ON CONVECTIVE COMPLEX DEVELOPMENT TOWARDS CNTRL MISSOURI (POSSIBLY CLIPPING SRN CWA COUNTIES) AFTER MIDNIGHT...AND HAVE KEPT MODESTLY HIGH CHANCE POPS HERE. FAR MORE UNCERTAINTY TOWARDS DEVELOPMENT DIVING SOUTH FROM IOWA/NEBRASKA...WITH ECMWF/RUC/HRRR SEEMINGLY INSISTENT ON CONVECTION DEVELOPING OVER NWRN IOWA...WITH NAM-WRF/GFS EXHIBITING A DEARTH OF QPF REFLECTION. THIS POTENTIAL COMPLEX MAY BE TIED TO A WAVE LIFTING NORTHEAST FROM CNTRL COLORADO (PER WV IMAGERY)...AND THE FIRST INDICATIONS OF LIFT MAY BE NOW TAKING SHAPE OVER FAR NWRN NEBRASKA. AS SUCH...MADE LITTLE OR NO CHANGES TO WX/POPS AFTER MIDNIGHT AS OF YET. ONLY OTHER MAJOR REVISION WAS THE INTRODUCTION OF HAZE IN A WEATHER MENTION AFTER MIDNIGHT. LIGHT HAZE ALREADY NOTED ABOUT THE MAJORITY OF THE AREA...AND WITH MOISTURE (DEWPOINTS GENERALLY IN THE MID 70S) TRAPPED BELOW A STEEPENING INVERSION OVERNIGHT...GENERALLY WET TOPSOILS...AND LIGHT ELY/SELY SFC WINDS...FEEL HAZE LAYER WILL BE VERY NOTABLE TOWARDS DAYBREAK. AS AN ASIDE...VERY IMPRESSIVE LARGE FIRE CAN BE NOTED ON AFTERNOON VISIBLE (AND EVEN IR) SATELLITE OVER NWRN OKLAHOMA (AN AREA WITH 110F+ TEMPS)...WITH A HUGE SMOKE PLUME EXTENDING DOWNSTREAM. LOCAL RADARS AND 3.9 MICRON SATELLITE IMAGERY STILL SHOW THIS AREA SMOLDERING AGGRESSIVELY WITH TEMPS STILL ABOVE 100F AND WINDS GUSTING TO NEAR 30 MPH. 21 && .PREVIOUS DISCUSSION... /355 PM CDT FRI JUL 10 2009/ TONIGHT...SHOWERS AND ISOLATED THUNDERSTORMS ONGOING ACROSS THE SOUTHERN HALF OF THE CWA DUE TO WEAK ISENTROPIC LIFT WILL CONTINUE THROUGH THE EVENING INTO TONIGHT. THERE IS SOME CONCERN THAT IF A COMPLEX OF STORMS COULD FIRE IN ERN NE THIS EVENING CORFIDI VECTORS AND UPPER LEVEL FLOW COULD TAKE THIS COMPLEX E ACROSS SRN IA AND THEN SOUTH THROUGH THE EASTERN CWA. THUSLY HAVE INCREASED POPS SLIGHTLY OVER THE EASTERN CWA. AFTER MIDNIGHT ANOTHER AREA OF SHOWERS AND THUNDERSTORMS MAY FIRE IN ANOTHER AREA OF INCREASED ISENTROPIC LIFT ACROSS THE SERN PORTION OF THE CWA. WITH CONSIDERABLE CLOUDINESS ACROSS THE CWA RAISED TEMPERATURES TONIGHT TO ACCOUNT FOR LACK OF RADIATIONAL COOLING. 73 FOR SATURDAY...CONVECTIVE ACTIVITY OVERNIGHT WILL DICTATE WHERE SYNOPTIC BOUNDARY FINALLY SETTLES. THERMAL CONTRAST ACROSS BOUNDARY IS NOT TOO GREAT...SO DO NOT ANTICIPATE MARKED DIFFERENCE IN TEMPERATURES AS COMPARED TO TODAY...WITH CLOUD COVER BEING THE MAY FACTOR IN ANY COOLING. WEAK ISENTROPIC LIFT COUPLED WITH A PARADE OF WEAK IMPULSES OVERTOPPING H5 RIDGE MAY IGNITE ISOLD TO SCATTERED CONVECTION MAINLY DURING THE MORNING AND AFTERNOON HOURS ALONG AND SOUTH/EAST OF A KIRKSVILLE TO PAOLA LINE. OVERALL CONFIDENCE IN DEVELOPMENT IS LOW...THUS CONTINUED TREND OF LOW CHANCE POPS. SUNDAY AND MONDAY...H5 RIDGE BUILDS/DRIFTS SLIGHT EASTWARD...AFFECTIVELY WASHING OUT OLD BOUNDARY ACROSS SOUTHERN MISSOURI. WITH SLIGHTLY GREATER H5 HEIGHTS...SHOULD SEE A SLIGHT INCREASE IN TEMPERATURES AND THUS DESTABILIZATION DURING THE AFTERNOON HOURS. GFS/ECMWF AND ENSEMBLES ALL IN GENERAL AGREEMENT IN DEVELOPING A MCS IN NEBRASKA AND TRACKING IT ALONG THE EDGE OF H5 CAP ACROSS THE NORTHEAST TWO-THIRDS OF FORECAST AREA. AXIS OF HIGHER POPS LIKELY WILL HAVE TO BE ADJUSTED BY LATER SHIFTS AS GENESIS AREA OF MCS BECOMES BETTER DEFINED. FOR NOW...BROADBRUSHED CHANCE POPS ACROSS ALL BUT EAST CENTRAL KANSAS/WEST CENTRAL MISSOURI. FOR THE REMAINDER OF EXTENDED RANGE...EC AND GFS ENSEMBLES CONSISTENT IN BUILDING/REORIENTING H5 RIDGE AXIS ACROSS THE SOUTHERN TIER OF STATES TUESDAY THROUGH WEDNESDAY. ADVECTION OF H8 TEMPERATURES OF 24-26C INTO WESTERN AND SOUTHERN PART OF CWA SIGNALS A MARKED BOUNCE IN TEMPERATURES. DO NOT ANTICIPATE A LOT OF SCOURING OF HUMID AIRMASS CURRENTLY IN PLACE ACROSS CWA...THUS LATER SHIFTS MAY NEED TO CONSIDER HOISTING HEAT WATCH...AS HOT TEMPERATURES COMBINED WITH HUMID CONDITIONS WILL LEAD TO INDICES APPROACHING OR EXCEEDING ADVISORY CRITERIA. THREAT OF EXCESSIVE HEAT LOOKS TO BE SHORT-LIVED AS RIDGE RETROGRADES AND PLACES FORECAST AREA UNDER NORTHWEST FLOW REGIME ONCE AGAIN. 24 && .AVIATION... FOR THE 06Z TAFS...WILL TREND TOWARD THE RUC AND OTHER SHORT TERM MODELS AND WILL GO WITH THE IDEA THAT DURING THE OVERNIGHT...UPPER JET SHOULD FOCUS STORMS JUST SOUTH AND WEST OF THE TERMINALS...AS THE LLJ RIDES OVER THE SURFACE FRONT JUST TO THE SOUTH. CAN NOT RULE OUT SOMETHING SLIDING NEAR THE KMKC SITE AS THE WARM FRONT MAY TRY TO LIFT NORTH AS A SURFACE WAVE SOUTH OF WICHITA TRIES TO MOVE TOWARD EMPORIA...SO WILL PLACE A MENTION OF VCTS. OVERALL CONFIDENCE IS FAIRLY LOW IN HOW THIS WILL EVOLVE AS THERE ARE SEVERAL WEAK SHORT WAVES IN THE FLOW STRUNG OUT ACROSS SOUTHERN KANSAS AND INTO SOUTHERN MISSOURI...WITH IT DIFFICULT TO TELL WHICH WILL BECOME THE DOMINANT WAVE OVERNIGHT. RIGHT NOW SEEING AN INCREASE IN ACTIVITY ON RADAR ASSOCIATED WITH A WAVE IN SOUTH CENTRAL KANSAS...WHICH MAY BE THE INITIATION OF THE MAIN ROUND OF STORMS. WILL HAVE TO WATCH HOW THINGS EVOLVE FOR LATE TONIGHT AS THE LLJ VEERS POSSIBLY IN THE WAKE OF THE MCS OVER SOUTH CENTRAL MISSOURI. THERE COULD BE SOME TAIL END DEVELOPMENT ALONG THE FRONT THAT MAY STILL BE NEAR THE KANSAS CITY AREA BEFORE SUNRISE. FOR NOW WILL NOT HAVE A MENTION OF STORMS IN THE LATE NIGHT PERIOD. THE OTHER SHORT TERM CONCERN...WITH THE WARM FRONT JUST SOUTH OF THE TAF SITES...AND PLENTY OF LOW LEVEL MOISTURE IN PLACE...THAT WE WILL SEE HZ/BR OVERNIGHT. ALREADY SEEING THIS DEVELOP...ALTHOUGH KMKC STILL AT 10SM. STILL THINK WITH THE FRONT NEARBY...EVEN THAT AIRPORT SHOULD SEE HZ/BR DEVELOP. NAM MODEL CONTINUES TO FORECAST SCT/BKN MVFR TYPE CIGS JUST AFTER SUNRISE WITH THE FRONT NEAR THE REGION...SO WILL LEAVE THE PREVIOUS TAF IDEA OF A BKN MVFR DECK IN THE GOING TAFS. REST OF FORECAST IS VERY LOW CONFIDENCE REGARDING IF OR WHEN ADDITIONAL THUNDERSTORMS DEVELOPMENT COULD OCCUR LATER IN THE TAF PERIOD...SO WILL KEEP IT DRY FOR NOW. PC && .EAX WATCHES/WARNINGS/ADVISORIES... MO...NONE. KS...NONE.
HAZARDOUS WEATHER OUTLOOK NATIONAL WEATHER SERVICE KANSAS CITY/PLEASANT HILL MO 1259 PM CDT FRI JUL 10 2009 KSZ025-057-060-102>105-MOZ001>008-011>017-020>025-028>033-037>040- 043>046-053-054-111800- 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- 1259 PM CDT FRI JUL 10 2009 THIS HAZARDOUS WEATHER OUTLOOK IS FOR NORTHWEST...NORTH CENTRAL AND WEST CENTRAL MISSOURI...AS WELL AS EXTREME EASTERN KANSAS. .DAY ONE...THIS AFTERNOON AND TONIGHT A STALLED FRONT DRAPED FROM SOUTHWEST IOWA INTO NORTHWEST KANSAS WILL BE THE FOCUS FOR MID TO LATE AFTERNOON THUNDERSTORM DEVELOPMENT WHICH WOULD LAST INTO THE EVENING HOURS. WITH THE HEAT OF THE AFTERNOON...AND A WEAK FRONTAL BOUNDARY STALLED ACROSS THE AREA...THE POSSIBILITY OF SEVERE WEATHER WILL ACCOMPANY ANY STORMS THAT OCCUR. THIS ACTIVITY MAY PUSH INTO PORTIONS OF NORTHWEST MISSOURI AND NORTHEAST KANSAS LATER THIS AFTERNOON AND EVENING. PRIMARY THREATS WILL BE FOR LARGE HAIL...DAMAGING STRAIGHT LINE WINDS...AND HEAVY RAINS THAT COULD LEAD TO FLOODING. .DAYS TWO THROUGH SEVEN...SATURDAY THROUGH THURSDAY THE THREAT FOR THUNDERSTORMS WILL LINGER ACROSS THE OUTLOOK AREA SATURDAY AND SUNDAY AS THE WEAK FRONTAL BOUNDARY SETTLES SOUTH. THIS SHOULD LIMIT THE BEST POTENTIAL FOR MORE STORMS TO AREAS FROM EAST CENTRAL KANSAS THROUGH CENTRAL MISSOURI. THE THREAT WILL THEN REFOCUS ACROSS THE IOWA BORDER REGION FOR SUNDAY NIGHT INTO MONDAY. AT THIS TIME THE PATTERN IS TOO CHAOTIC TO DETERMINE WHAT THE PRIMARY SEVERE THREATS WILL BE WITH ANY OF THE STORMS THAT OCCUR...SO INTERESTED PARTIES SHOULD CHECK BACK FOR FURTHER UPDATES THROUGH THE WEEKEND. .SPOTTER INFORMATION STATEMENT... SPOTTER ACTIVATION MAY BE NEEDED LATER THIS EVENING...MAINLY ALONG AND WEST OF INTERSTATE 35. DEROCHE
SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE KANSAS CITY/PLEASANT HILL MO
256 AM CDT SAT JUL 11 2009
KSZ105-MOZ043-053-054-110830-
BATES-CASS-HENRY-JOHNSON-
256 AM CDT SAT JUL 11 2009
...SIGNIFICANT WEATHER ALERT FOR CASS...NORTHEASTERN BATES...
SOUTHEASTERN JOHNSON AND SOUTHWESTERN HENRY COUNTIES UNTIL 330 AM
CDT...
AT 254 AM CDT...NATIONAL WEATHER SERVICE DOPPLER RADAR WAS TRACKING
STRONG THUNDERSTORMS ALONG A LINE EXTENDING FROM CLEVELAND TO
ARCHIE...MOVING EAST AT 25 MPH.
WINDS UP TO 50 MPH ARE POSSIBLE WITH THESE STORMS ALONG WITH
FREQUENT LIGHTNING AND HEAVY RAINFALL.
THESE STORMS WILL BE NEAR...
ADRIAN AROUND 300 AM CDT.
ARCHIE AROUND 305 AM CDT.
PECULIAR AND BUTLER AROUND 315 AM CDT.
HARRISONVILLE...GARDEN CITY AND EAST LYNNE AROUND 330 AM CDT.
THE TOWNS OF WEST LINE...STILLWELL...PASSAIC AND BALLARD ARE ALSO IN
THE PATH OF THESE STORMS.
LAT...LON 3824 9439 3864 9462 3873 9461 3874 9467
3883 9472 3878 9431 3822 9391
PCThe Pleasant Hill radar (KEAX), 62 km away, was scanning. The volume nearest the first event began at 08:11 UTC.
3 thunderstorm wind. Local standard time, as filed.
Large trees were reported uprooted, with several tree limbs up to 8 inches in diameter broken off.
Trees were reported down with power outages also reported.
Several tree limbs were broken off, by thunderstorm wind gusts to 60 mph.
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, 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: 188271, 188270, 188272.