A strong push of theta-e took place during the early morning hours. A stationary frontal boundary remained south of Iowa, setting the stage for another MCS to develop.
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 DMX wrote it up.
A strong push of theta-e took place during the early morning hours. A stationary frontal boundary remained south of Iowa, setting the stage for another MCS to develop. The airmass was relatively unstable with CAPE around 2000 J/kg just south of the front. The low level jet was not real strong, in the 25 to 30 kt range. Thunderstorms developed after midnight over eastern Nebraska. The storms moved into southwest Iowa and lifted northeast into the central counties during the predawn hours. The storms accelerated as they moved through Iowa, producing high winds across the southern third of the state. Trees and power lines were toppled. Damage was reported to roofs in Taylor and Clarke Counties by the high winds. Heavy rain fell in the Ottumwa area, with reports of 2 inches in one hours time. Flash flooding occurred in part of the city with 2 feet of flowing water reported in parts of the downtown area.
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 Des Moines, IA wrote its last area forecast discussion before the first event at Jun 22, 2:41 AM CST, 20 minutes earlier.
AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE DES MOINES IA 341 AM CDT TUE JUN 22 2010 .SHORT TERM /TODAY/... LOTS OF UNCERTAINTY AGAIN TODAY AS MORNING MCS IS ARRIVING A BIT EARLY AND BEHAVING DIFFERENTLY WITH STRONG POST MCS DRYING AND WINDS ...LIKELY ASSOCIATED WITH SUBSIDENCE IN MID LEVELS. CURRENT MOVEMENT WOULD PUT BACK EDGE ALMOST TO I-35 BY 12-13Z...WHICH WOULD ALLOW PLENTY TIME FOR HEATING UP AND DESTABILIZATION DURING THE DAYLIGHT HOURS. HAVE GONE WITH THE HIGHEST POPS FOR THIS MORNING. NONE OF THE NUMERICAL MODELS IS HANDLING THE CURRENT ACTIVITY VERY WELL...BUT ALL INDICATE A WARM ADVECTION SURGE THAT IS STRONGER THAN THE PAST FEW DAYS AND MAY FINALLY PUSH THE SURFACE BOUNDARY NORTH. WILL PLAY IT CONSERVATIVE AND NOT PUSH THE BOUNDARY QUITE AS FAR NORTH AS THE MODELS...SINCE NONE HAVE MUCH IN THE WAY OF MORNING THUNDERSTORMS. AND AS ALWAYS...IT REMAINS TO BE SEEN WHETHER TRAILING CONVECTION OVER KANSAS AND NEBRASKA HOLDS TOGETHER...BUT IF IT DOES...THE BOUNDARY WOULDN'T MAKE MUCH PROGRESS NORTH AT ALL. WHETHER THE BOUNDARY IS NORTH OR SOUTH...THERE WILL BE STRONG INSTABILITY TO ITS SOUTH AND AN INCREASING LOW-LEVEL JET FOR CONVERGENCE. KEPT A LOW POP OVER THE NORTH HALF OF THE FORECAST AREA FOR THIS AFTERNOON...BUT REALLY THINK THAT CHANCES FOR REDEVELOPMENT WILL BE MUCH BETTER AFTER 00Z. IF STORMS WERE TO DEVELOP OVER THE NORTHERN HALF OF IOWA...THERE WILL BE PLENTY OF SHEAR AND INSTABILITY FOR ROTATING STORMS AND SEVERE WEATHER. .LONG TERM /TONIGHT THROUGH SATURDAY/... THE BIG QUESTION THROUGH WEDNESDAY NIGHT IS WHERE WILL THE FRONTAL BOUNDARY BE. THE GENERAL CONSENSUS OF THE MODELS IS FOR THE FRONT TO LIFT TO THE HIGHWAY 20 CORRIDOR BY LATE THIS AFTERNOON OR EARLY EVENING. WE ARE EXPECTING ANOTHER MCS TONIGHT TO ROLL ACROSS NORTHERN IOWA AND WITH THE ABUNDANT SHEAR AND CAPE IN PLACE IT SHOULD BE QUITE ACTIVE ALONG AND NORTH OF THE FRONTAL BOUNDARY. I WILL BE HITTING THE WORDING HARD IN THE HWO AND ZONES FOR THE NORTHERN THIRD. LINGERING CHANCES FOR THUNDERSTORMS WEDNESDAY AS THE UPPER WAVE PUSHES THROUGH THEN A RESPITE. UPPER RIDGING TRIES TO BUILD INTO THE UPPER MIDWEST ON THURSDAY AND FRIDAY BUT THE MODELS DIFFER ON THE STRENGTH OF A WAVE PROGGED TO PUSH INTO THE REGION FRIDAY/SATURDAY. I PUT SMALL POPS ACROSS THE NORTH LATE FRIDAY AND SATURDAY FOR NOW AND WILL ADJUST AS RUNS BECOME MORE CONSISTENT. OTHERWISE...NOT MANY CHANGES MADE TO TEMPS. IF ANYTHING A TWEAKED THEM FOR CONVECTIVE TRENDS. && .AVIATION... 22/06Z...IMMEDIATE CONCERNS ARE REMNANT CONVECTION NEAR KOTM...AND LARGER MCS APPROACHING OVER KS/NE. EXTRAPOLATION SUGGESTS COMPLEX WILL AT LEAST CLIP KDSM BY 10Z...AND AFFECT KOTM MORE SO TOWARD 12Z SO HAVE INCLUDED VFR VCSH/VCTS/CB WORDING FOR FOUR HOURS HITTING KOTM HARDER. BEYOND CRITICAL TAF PERIOD...HAVE LITTLE CONFIDENCE IN FORECASTING CONVECTIVE TRENDS SO WILL LEAVE ANY MENTION OUT FOR NOW. VARIOUS SCENARIOS INCLUDE MORE WIDESPREAD CONVECTION TUE MORNING AFFECTING KFOD/KMCW/KALO AS WELL AS SOUTHERN SITES...AND/OR ADDITIONAL DEVELOPMENT DURING PEAK HEATING OF THE AFTERNOON IF AND WHEN CURRENT NRN MO FRONT LIFTS NORTHWARD. PREFERRED STRATEGY IS TO HIGHLIGHT CRITICAL TAF PERIOD TO DEAL WITH THESE CONTINGENCIES IN EACH SUBSEQUENT ISSUANCE OR AMENDMENTS. && && .DMX WATCHES/WARNINGS/ADVISORIES...NONE. && SHORT TERM...JUNGBLUTH LONG TERM...FAB AVIATION...SMALL
HAZARDOUS WEATHER OUTLOOK NATIONAL WEATHER SERVICE DES MOINES IA 331 PM CDT MON JUN 21 2010 IAZ004>007-015>017-023>028-033>039-044>050-057>062-070>075-081>086- 092>097-222045- EMMET-KOSSUTH-WINNEBAGO-WORTH-PALO ALTO-HANCOCK-CERRO GORDO- POCAHONTAS-HUMBOLDT-WRIGHT-FRANKLIN-BUTLER-BREMER-SAC-CALHOUN- WEBSTER-HAMILTON-HARDIN-GRUNDY-BLACK HAWK-CRAWFORD-CARROLL-GREENE- BOONE-STORY-MARSHALL-TAMA-AUDUBON-GUTHRIE-DALLAS-POLK-JASPER- POWESHIEK-CASS-ADAIR-MADISON-WARREN-MARION-MAHASKA-ADAMS-UNION- CLARKE-LUCAS-MONROE-WAPELLO-TAYLOR-RINGGOLD-DECATUR-WAYNE-APPANOOSE- DAVIS- 331 PM CDT MON JUN 21 2010 THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF CENTRAL IOWA. .DAY ONE...THIS AFTERNOON AND TONIGHT THERE IS A SLIGHT CHANCE FOR SEVERE WEATHER LATE THIS AFTERNOON AND OVERNIGHT TONIGHT. A FEW SUPER CELL THUNDERSTORMS ARE POSSIBLE SOUTH OF INTERSTATE 80 BETWEEN 5 AND 10 PM THIS EVENING AND WOULD BRING THE POTENTIAL FOR GOLF BALL SIZED HAIL...70 MPH WINDS AND ISOLATED TORNADOES. ADDITIONAL SCATTERED STORMS ARE POSSIBLE OVER THE REMAINDER OF THE AREA AFTER 10 PM WITH QUARTER SIZED HAIL AND 60 MPH WINDS POSSIBLE. LOCALIZED HEAVY RAINFALL MAY OCCUR. .DAYS TWO THROUGH SEVEN...TUESDAY THROUGH SUNDAY ADDITIONAL SEVERE STORMS ALONG WITH HEAVY RAINFALL ARE POSSIBLE TUESDAY INTO WEDNESDAY. A SLIGHT CHANCE OF THUNDERSTORMS WILL RETURN THURSDAY NIGHT AND CONTINUE FOR ALL OR PART OF THE AREA THROUGH SUNDAY. .SPOTTER INFORMATION STATEMENT... SPOTTER ACTIVATION MAY BE NEEDED BETWEEN 5 PM AND 10 PM THIS EVENING SOUTH OF INTERSTATE 80. DONAVON
SPECIAL WEATHER STATEMENT NATIONAL WEATHER SERVICE DES MOINES IA 1025 PM CDT MON JUN 21 2010 IAZ097-220400- DAVIS- 1025 PM CDT MON JUN 21 2010 AT 1020 PM CDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A STRONG THUNDERSTORM OVER EXTREME SOUTH CENTRAL DAVIS COUNTY...MOVING EAST AT 30 MPH. PENNY SIZE HAIL...BRIEF HEAVY DOWNPOURS...ARE POSSIBLE WITH THIS STORM. SEEK SHELTER IN A STURDY STRUCTURE UNTIL THIS STORM HAS PASSED. BEITLICH
SPECIAL WEATHER STATEMENT NATIONAL WEATHER SERVICE DES MOINES IA 1032 PM CDT MON JUN 21 2010 IAZ085-096-220400- APPANOOSE-MONROE- 1032 PM CDT MON JUN 21 2010 AT 1029 PM CDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A STRONG THUNDERSTORM OVER NORTH CENTRAL APPANOOSE COUNTY...MOVING EAST AT 20 MPH. NICKEL SIZE HAIL...WINDS UP TO 50 MPH...FREQUENT CLOUD TO GROUND LIGHTNING...BRIEF MODERATE DOWNPOURS...ARE POSSIBLE WITH THIS STORM. * THE THUNDERSTORM WILL BE NEAR... MORAVIA BY 1050 PM CDT... UNIONVILLE BY 1100 PM CDT... GUSTY WINDS MAY CAUSE SMALL BRANCHES TO BE BLOWN DOWN...AND LOOSE OBJECTS TO BLOW AROUND. STAY AWAY FROM HIGH OBJECTS OUTDOORS SUCH AS TREES. SEEK SHELTER IN A STURDY STRUCTURE UNTIL THIS STORM HAS PASSED. PODRAZIK
SPECIAL WEATHER STATEMENT NATIONAL WEATHER SERVICE DES MOINES IA 1100 PM CDT MON JUN 21 2010 IAZ096-097-220500- APPANOOSE-DAVIS- INCLUDING THE CITIES OF...CENTERVILLE...BLOOMFIELD 1100 PM CDT MON JUN 21 2010 ...STRONG THUNDERSTORMS CONTINUE THIS EVENING... SCATTERED THUNDERSTORMS CONTINUE TO AFFECT PORTIONS OF SOUTHEAST IOWA LATE THIS EVENING. SOME OF THESE STORMS MAY BE STRONG PRODUCING UP TO NICKEL SIZED HAIL AND LOCALLY HEAVY RAINS. THE STORMS WILL PRIMARILY AFFECT EASTERN APPANOOSE AND DAVIS COUNTIES THROUGH 100 AM. SMALL
The Des Moines radar (KDMX), 147 km away, was scanning. The volume nearest the first event began at 09:00 UTC.
14 thunderstorm wind, 1 heavy rain, 1 flash flood. Local standard time, as filed.
Taylor County Emergency Manager relayed roof damage occurred south of Highway 2 on Highland Ave.
At least part of a roof was blown off of a home.
Tree branches 12 to 15 inches in diameter blown down. One tree was uprooted.
Six inch tree branches were down.
A 20 foot wooden privacy fence was blown down and doors to a plastic shed were blown out.
Four to six inch tree limbs downed by high winds. Also, 2 inches of rain fell in an hour with English Creek out of its banks.
Partial road closure on Highway 5 about one quarter mile east of Hartford due to water from Butcher Creek.
Damage to tree limbs.
Damage reported to trees and power lines.
Wind gusts as high as 60 MPH. Spotter also notes reports of street flooding.
West snd St in Ottumwa was closed from the 1100 to 1500 block. Up to 2 feet of water was reported on Harrows Branch Road.
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, June 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: 226233, 226230, 227160, 227157, 226232, 227163, 226231, 227162, 226226, 226242, 236011, 226227, 227161, 226228, 226229, 226234.