A boundary was pushing through the state with ongoing convection through central Iowa through the day. As the boundary neared the area, the convection intensified and impacted central and southern Iowa in the evening to early morning hours.
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 boundary was pushing through the state with ongoing convection through central Iowa through the day. As the boundary neared the area, the convection intensified and impacted central and southern Iowa in the evening to early morning hours. Two thunderstorm complexes moved through portions of central and southern Iowa with very heavy rainfall causing flash flooding. The severe thunderstorm complexes produced some hail but mainly strong damaging winds. Precipitable water values were near 2 inches in some areas with deep warm cloud depths during the event. This heavy rainfall further exacerbated conditions as some of the area had just received heavy rainfall in previous days. This led to some extended flooding for a few days and flooding on some area rivers. Several locations reported in excess of 4 inches of rain, while one location in Warren County reported over 7.50 inches of rainfall. The Emergency Manager for Marion County mentioned widespread reports of 8 to 10 inches with one report close to 12 inches of accumulated rainfall over the past few days.
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 Jul 27, 10:33 PM CST, 1 hour 27 minutes earlier.
AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE DES MOINES IA 1133 PM CDT MON JUL 27 2015 .SHORT TERM /TONIGHT/... ISSUED AT 416 PM CDT MON JUL 27 2015 FORECAST CONCERNS CONTINUE TO REVOLVE AROUND PRECIPITATION TRENDS. ONGOING CONVECTIVE SYSTEM ACROSS CENTRAL IOWA THROUGHOUT THE DAY TODAY WILL CONTINUE TO INFLUENCE CONVECTIVE TRENDS THROUGH THE OVERNIGHT. HAVE KEPT POPS ACROSS THE AREA AS INSTABILITY WILL ALLOW ONGOING PRECIPITATION TO CONTINUE TO PUSH EAST AND DROP SOUTHEAST. IN ADDITION...CONCERNS FOR THE AFTERNOON REDEVELOPMENT TO THE WEST. EXPECT BEST CHANCE TO BE FURTHER WEST INTO EASTERN IOWA ALONG BOUNDARY...HOWEVER...THETA-E ADVECTION IS EXPECTED TO INCREASE ACROSS WESTERN IOWA IN THE LATE AFTERNOON HOURS WHICH MAY SPARK ADDITIONAL THUNDERSTORMS. CURRENT MESO ANALYSIS SHOWS CAPPING ACROSS THIS AREA...AND HAVE TRENDED PRECIPITATION IN THIS AREA DOWN...EXPECTING CAP TO HOLD. NEXT FOCUS WILL BE PRECIPITATION TRENDS OVERNIGHT AS WAVE PUSHES NORTH AHEAD OF BOUNDARY IN THE DAKOTAS. MODELS CONTINUE TO BE FASTER WITH THIS SOLUTION...AND HAVE TRENDED THIS WAY. WILL BE SOME SEVERE POTENTIAL WITH INSTABILITY REMAINING ACROSS THE AREA...THOUGH MAIN CONCERN WILL BE WITH HEAVY RAIN POTENTIAL. PWAT VALUES NEAR 1.8 INCHES WITH GOOD MOISTURE TRANSPORT INTO THE REGION AND WARM CLOUD DEPTHS. GIVEN ANTICIPATED BEST FORCING FURTHER NORTH OF IOWA...AND QUICK PROGRESSION OF SYSTEM...WILL KEEP FLASH FLOOD HEADLINES OUT FOR NOW. .LONG TERM /TUESDAY THROUGH MONDAY/... ISSUED AT 416 PM CDT MON JUL 27 2015 WE HAVE AN ACTIVE DAY LINED UP FOR TUESDAY...FOLLOWED BY A MUCH MORE CLIMATOLOGICAL LEANING FCST PERIOD FOR THE REST OF THE LONG TERM. MODELS IN GOOD AGREEMENT WITH PUSHING A COLD FRONT THROUGH THE CWA FROM NW TO SE DURING TUESDAY. THREE MAJOR CONCERNS FOR TUESDAY ARE STRONG TO SEVERE THUNDERSTORM POTENTIAL...HEAVY RAINFALL POTENTIAL...AND NEAR HEADLINE HEAT INDEX VALUES. FOR TUE HEAVY RAIN POTENTIAL...PWATS IN THE 2.1 TO 2.25 INCH RANGE...ESPECIALLY OVER OUR NE CWA...ARE AROUND +3 TO +4 STD DEV. NAM HAS PWATS APPROACHING 2.5 INCHES. IN TERMS OF MOISTURE AND DWPTS...NAM ON THE HIGHER END AM LEANING TOWARDS IT SINCE IT IS INITIALIZING WELL...PLUS THE TIME OF YEAR SUPPORTS MOIST. THE GFS IS TOO DRY PER USUAL. PLENTY OF MOISTURE TRANSPORT VIA 30 KT LLJ AND PLENTY OF SFC MOISTURE CONV WITH COLD FROPA. MIXING RATIOS ABOVE 8 G/KG PLUS 0-6 KM MUCAPES ABOVE 1500 J/KG WILL SUPPORT UPWARD MOISTURE FLUX. TIME OF YEAR WOULD TYPICALLY BE A HUGE NEGATIVE FOR FLOODING/FLASH FLOODING POTENTIAL. HOWEVER...SIGNIFICANT RAINFALL OVER THE PAST 48 HOURS IN SOME LOCATIONS MAY LEAVE SOME AREAS FAIRLY SATURATED. FOR TUE SVR WX POTENTIAL...MAIN FOCUS WILL BE DAMAGING WINDS AND SLIGHT TOR THREAT. WITH PWATS EXPECTED TO BE SO HIGH...UPDRAFTS WILL LIKELY BE WATER LOADED...MAKING SEVERE HAIL PRODUCTION DIFFICULT. BOTH GFS AND NAM PICK UP ON A POCKET OF 200 M2/S2 0 TO 3 KM HELICITY WITH THE BOUNDARY TO OUR NORTH. LCL HEIGHTS WELL BELOW 1000M. IN SHORT...NOT AN OUTBREAK ENVIRONMENT...BUT WORTH WATCHING. FOR HEAT POTENTIAL...WENT WITHOUT ANY HEADLINES FOR NOW. MORNING PRECIP/CLOUD COVER PLUS TIMING OF BOUNDARY ARRIVAL WILL LIKELY KEEP TEMPS DOWN VERSUS FCST IN PREVIOUS FEW DAYS. REGARDLESS OF SFC TEMPS...WILL STILL BE HOT AND HUMID WITH SFC DWPTS IN THE MID TO UPPER 70S. HEAT INDEX VALUES WILL LIKELY TOP OUT IN THE UPPER 90S TO LOW TRIPLE DIGITS IN AND SE OF THE DSM METRO. OVERNIGHT SHIFT MAY NEED TO ISSUE ADVISORY IN OUR SE. THE FRONT AND ANY LINGERING PRECIP SHOULD BE EAST OF OUR CWA BY SUNRISE WEDNESDAY. A SFC ANTICYCLONE WILL HELP KEEP WEDNESDAY AND THURSDAY QUIET AND DRY. 850 MB TEMPS DROP TO THE 14C TO 18C RANGE WHICH WILL HELP PUSH TEMPS DOWN TO THE LOW 80S FOR WEDNESDAY. FOR THE MIDDLE TO END OF THE WEEK...WE RETURN TO ZONAL FLOW. MID LEVEL WINDS ARE ABOUT +1 TO +2 STD DEV FROM THE WEST. GIVEN ALL OF THIS...LEFT BROAD-BRUSHED POPS THROUGH THE WEEKEND IN ANTICIPATION OF SHORTWAVE TRAIN EXPECTED TO START CHUGGING AGAIN. 850MB TEMPS RETURN TO THE 19C TO 22C RANGE WHICH IS NEAR NORMAL FOR THIS TIME OF YEAR. SUBSEQUENTLY...HAVE HIGHS CLOSE TO CLIMO...IN THE MID TO UPPER 80S. && .AVIATION...28/06Z ISSUED AT 1133 PM CDT MON JUL 27 2015 WARM FRONT ALOFT/SFC JUST TO WEST OF AREA THIS EVENING. MCS OVER THE DAKOTAS/NEBRASKA WILL BEGIN TO EXPAND EAST/SOUTHEAST BETWEEN 09-13Z WITH AREA OF LIFT ACROSS NORTH CENTRAL IOWA BY 09-10Z AND A GRADUAL EXPANSION FROM WEST CENTRAL/NORTH CENTRAL BY 10-12Z. HAVE DELAYED ARRIVAL IN TAFS WITH UPDATED HRRR MODEL RUNS...SOUTHERN SITES AT KDSM/KOTM SHOULD SEE LESS DURATION OF THUNDER BETWEEN 11-15Z THAN NORTH. AS MAIN COLD FRONT MOVES INTO THE AREA... ANOTHER ROUND OF STORMS IS EXPECTED FROM 20-00Z LINGERING AFT 29/00Z OVER THE EAST. CONFIDENCE ON TIMING IS STILL MODEST...SO HAVE KEPT VICINITY WORDING FOR NOW./REV && .DMX WATCHES/WARNINGS/ADVISORIES... NONE. && SHORT TERM...AWB/KA LONG TERM...KOTENBERG AVIATION...REV
HAZARDOUS WEATHER OUTLOOK NATIONAL WEATHER SERVICE DES MOINES IA 429 PM CDT MON JUL 27 2015 IAZ004>007-015>017-023>028-033>039-044>050-057>062-070>075- 081>086-092>097-282130- 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- 429 PM CDT MON JUL 27 2015 THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF CENTRAL IOWA. .DAY ONE...TONIGHT SCATTERED THUNDERSTORMS ARE EXPECTED TONIGHT...MAINLY WEST OF INTERSTATE 35. .DAYS TWO THROUGH SEVEN...TUESDAY THROUGH SUNDAY THUNDERSTORMS ARE LIKELY THROUGH TUESDAY NIGHT. THERE IS A SLIGHT RISK OF SEVERE WEATHER WITH STRONG WINDS AND AN ISOLATED TORNADO OR TWO THE PRIMARY THREATS. HEAVY RAINFALL IS ALSO LIKELY WITH THESE STORMS...ESPECIALLY OVER NORTHERN IOWA. THUNDERSTORMS RETURN TO THE FORECAST ON SATURDAY AND SUNDAY. AS OF NOW...THE SEVERE THREAT IS LOW. .SPOTTER INFORMATION STATEMENT... SPOTTER ACTIVATION MAY BE NEEDED TUESDAY AFTERNOON AND EVENING. ANY RAINFALL AMOUNTS ARE APPRECIATED. KOTENBERG
PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE DES MOINES IA
914 PM CDT MON JUL 27 2015
...TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
...DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE....
..REMARKS..
0900 PM HEAVY RAIN GOWRIE 42.28N 94.29W
07/27/2015 M2.30 INCH WEBSTER IA TRAINED SPOTTER
&&
BFPRELIMINARY LOCAL STORM REPORT...SUMMARY
NATIONAL WEATHER SERVICE DES MOINES IA
915 PM CDT MON JUL 27 2015
...TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
...DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE....
..REMARKS..
0900 PM HEAVY RAIN GOWRIE 42.28N 94.29W
07/27/2015 M2.30 INCH WEBSTER IA TRAINED SPOTTER
0431 PM FLASH FLOOD 3 S UDELL 40.74N 92.74W
07/27/2015 APPANOOSE IA LAW ENFORCEMENT
WATER OVER THE ROAD AT 2 LOCATIONS BETWEEN
265TH AVE AND 296TH AVE ON HIGHWAY 2. WATER
FLOODING UNDERPASS AT HIGHWAY 2 AND 296TH
AVE.
0431 PM FLASH FLOOD KNOXVILLE 41.32N 93.10W
07/27/2015 MARION IA LAW ENFORCEMENT
NUMEROUS REPORTS OF COUNTY ROADS WASHED OUT
THROUGHOUT THE COUNTY.
&&
NWS DES MOINES IA
IRIS SYSTEMPRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE DES MOINES IA
950 PM CDT MON JUL 27 2015
...TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
...DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE....
..REMARKS..
0930 PM HEAVY RAIN 1 NNW KNOXVILLE 41.33N 93.10W
07/27/2015 M2.10 INCH MARION IA TRAINED SPOTTER
&&
BFThe Des Moines radar (KDMX), 23 km away, was scanning. The volume nearest the first event began at 05:57 UTC.
40 thunderstorm wind, 25 heavy rain, 20 flash flood, 5 lightning, 5 flood, 3 hail. Local standard time, as filed.
ASOS/AWOS daily/storm total observation from July 28 reported heavy rainfall of 2.44 inches.
Coop observer reported heavy rainfall of 4.26 inches over the last 24 hours, since 7 am the previous day.
Coop observer reported heavy rainfall of 3.02 inches over the last 24 hours.
Public reported heavy rainfall with a total of 1.94 inches.
Public reported heavy rainfall of 4.00 inches.
Public reported measured heavy rainfall of 7.56 inches through 10:30 pm.
CoCoRaHS report of heavy rainfall of 5.96 inches for the day.
Trained spotter reported storm total heavy rainfall of 4.00.
Trained spotter reported heavy rainfall of 5.44 inches storm total.
Trained spotter reported 3.50 inches since 6 pm and 4.15 inches for the day.
NWS Employee reported storm total heavy rainfall of 1.73 inches at the office.
Trained spotter reported heavy rainfall of 2.30 inches.
Emergency manager reported trees and power lines down, including a tree on a house.
Trained spotter reported heavy rainfall of 2.38 inches. Time estimated between 4:30 pm and report time via radar.
Trained spotter emptied an estimated 4.00 inches from their rain gauge today.
A large tree branch was down on a power line at the Meskwaki Settlement.
A large tree was blown over in town. Sweet corn was also blown over.
Public reported measured heavy rainfall of 2.40 inches.
CoCoRaHS reported heavy rainfall of 5.25 inches so far with moderate to heavy rain ongoing at time of report.
Trained spotter reported heavy rainfall of 4.50 inches since 5 pm with a full day total of 5.30 inches thus far.
Emergency manager reported a tree down across Highway 92. Time estimated by radar.
Public reported large tree snapped in half with a diameter of approximately 10 to 12 inches.
Several large trees were down in the area.
CoCoRaHS report of heavy rainfall of 2.6 inches over the last 2 hours.
A power pole was blown down. Several trees were down on power lines in the town as well.
A large tree was down on a power line.
A large tree was down on a power line.
Large tree limbs of 3 to 4 inches were down and the power was out. Large hail was also reported a few minutes earlier.
Lightning struck a vehicle starting it on fire.
Lightning struck a telephone pole starting a fire.
A large tree was down across the road at 150th Pl and Pratt Drive.
Trained spotter reported heavy rainfall of 1.80 inches since 6 pm.
A large tree limb was down on a power line.
A large tree was down on a power line.
A large tree was downed.
A large tree was down on a power line.
Lightning struck a transformer and started a fire.
Five to 6 large trees were blown down and power lines were blown down as well.
Lightning struck an LP tank and freon line starting a fire.
A large tree fell on an apartment building. Four of the apartments had to be evacuated.
Large tree limbs snapped off.
Trained spotter reported heavy rainfall of 1.80 inches.
Public reported large tree limb down 10 to 12 inches in diameter.
Trained spotter reported heavy rainfall of 2.00 inches. Start time estimated via radar.
Emergency manager reported storm total heavy rainfall of 5.50 inches. Start time radar estimated.
Wind gust of 51 kts reported via Iowa DOT RWIS station.
Trained spotter reported numerous tree limbs down on houses and powerlines. Time estimated from radar. An estimated 14 inch diameter tree was snapped near the base. Power was out in portions of town.
Trained spotter reported heavy rainfall of 1.80 inches from previous evening through the morning.
Trained spotter reported telephone pole knocked over at intersection of Clay and Gateway. Wind gusts estimated at 60-65 mph.
Broadcast media reported estimated wind gust of 55kts.
A large tree was down in town. Report from a WHO news article.
A large tree was down 18 inches in diameter with some large limbs down as well. Two inches of rain fell in about 30 minutes.
Trained spotter reported nickel sized hail.
Westcom dispatch reported fire due to lightning strike along 86th st.
Emergency Manager reported voluntary evacuations of residences due to flooding from Volunteer Creek. This was a delayed report and time estimated by radar.
Water was reported over the road at 190th St between T and U Avenues. Standing water was also reported in Adel.
Public reported nickel sized hail.
Emergency Manager reported tree blown over by the thunderstorm winds. Estimated 2.5 feet in diameter.
Department of Transportation reported flooding on Iowa Highway 28 at the 0.5 mile marker. Delayed report.
Large tree uprooted about 2.5 to 3 ft in diameter. Four to 5 inches of rain received.
Department of Transportation reported water over the road on I-35 Northbound at mile marker 61.
Coop observer reported heavy rainfall of 3.40 inches. Start time radar estimated.
Strong winds of at least 60 mph and several reports of large tree limb damage was reported across much of Lucas County.
Emergency Manager reported that the police and fire departments are working on an incident where water is coming into the main floor of a local home.
Law Enforcement in Madison County reported widespread street flooding throughout the county.
Public reported storm total heavy rainfall of 2.30 inches.
The Osceola AWOS recorded a measured gust of 51 kts at 9:15 PM CDT.
Emergency Manager reported several feet of water in VA hospital building.
Three to four inch tree limbs down and 5 gallon buckets blown around.
Large tree limbs down north of town and crops blown over.
Trained spotter reported large tree down approximately 20 inches in diameter and crops blown down.
Winds of 65 to 70 mph were estimated across much of the county along with several reports of large tree limb damage.
A large tree of 20 inches in diameter was down.
Department of Transportation reported flooding on Iowa Highway 92 at the 144 mile marker. Delayed report.
Emergency Manager reported US 65/69 south of Indianola closed due to water flowing over the road. Additional sections of US 65/69 closed elsewhere in the county also due to water flowing over the road. Delayed report and time estimated via radar.
Public reported Iowa Highway 5 west of Hartford closed due to water flowing over the road. Delayed report and time estimated via radar.
Emergency Manager reported Iowa Highway 5 southeast of Carlisle closed due to water flowing over the road. Delayed report and time estimated from radar.
Trained spotter reported estimated wind gust of 65 mph.
The Emergency Manager sent a list of all the roads impacted by water. They included the following: Hwy 5 at the Hartford railroad underpass, Hwy 92 at the South River, 20th Ave from Hwy 92 to Jersey St., Kennedy St. just east of 150th Ave with signs of it being washed out and 4 feet of water over the road, 180th and Hwy 92, Hwy S23 and Grimes had 3 feet of water over the road, Interstate 35 between mile marker 57 and 59, Hwy 92 and the railroad overpass by Beech and S31, 165th Ave and Clarke St. had 2 feet over the road, Hwy 92 west of S23, Fulton both at 115th and around S23, G24 from west of R57 to 73rd and from 115th to Hwy 65/69, Idaho St. east of Hwy 28. Hwy 28 on the north edge of Martensdale, S23 north of Hwy 92, and at 165th and Buchanan.
The Centerville AWOS recorded a measured gust of 62 kts at 10:05 PM CDT.
Trained spotter reported large tree limbs down.
Department of Transportation reported flooding on Iowa Highway 5 at mile marker 66 and 67. Delayed report.
A 10 inch diameter tree was snapped off at the top.
Trained spotter reported large tree limbs down.
Winds of 65 to 70 mph were estimated across western Davis County with several large limbs down around the county.
Law Enforcement reported a pond in town has completely filled and is overflowing and running across the road. Depth of the water is unknown.
Emergency Manager reported several roads in Corning and Prescott have street flooding. Also reported several gravel roads south of Highway 34 are flooded.
Emergency Manager reported water about a foot deep flowing over Kale Road in northeast portion of Corning.
A road was damaged from floodwaters.
Emergency Manager reported Loomis Ave between 5th and Railroad in southern Corning is closed due to water over the road.
Department of Transportation reported multiple secondary roads flooded. Delayed report and time estimated from radar.
Emergency Manager reported Cumming Road/County Road G4R remained closed due to water flowing over them between 155th St and Badger Creek Rd. Additionally many secondary roads across the county remain closed with water flowing over them.
Law Enforcement reported Iowa Highway 92 remained closed due to water flowing over it, west of Pleasantville. In addition several secondary roads across the county remain closed with water flowing over them. Around 200 to 300 homes in the Pleasantville area had some degree of water damage as well.
Law Enforcement reported that several secondary roads across the southern portion of the county remain closed due to water over the road. The Emergency Manager reported that 200 to 300 homes in the Pleasantville area sustained some degree of water damage.
The Emergency Manager sent a list of all the roads impacted by water and many continued to be impacted by water into the morning/afternoon hours. They included the following: Hwy 5 at the Hartford railroad underpass, Hwy 92 at the South River, 20th Ave from Hwy 92 to Jersey St., Kennedy St. just east of 150th Ave with signs of it being washed out and 4 feet of water over the road, 180th and Hwy 92, Hwy S23 and Grimes had 3 feet of water over the road, Interstate 35 between mile marker 57 and 59, Hwy 92 and the railroad overpass by Beech and S31, 165th Ave and Clarke St. had 2 feet over the road, Hwy 92 west of S23, Fulton both at 115th and around S23, G24 from west of R57 to 73rd and from 115th to Hwy 65/69, Idaho St. east of Hwy 28. Hwy 28 on the north edge of Martensdale, S23 north of Hwy 92, and at 165th and Buchanan. Damage amounts listed in the flash flood entry.
Department of Ttransportation reported water over the road on Iowa Highway 92 at approximately mile marker 178. Initial report of 5 to 6 inches of water on the road. Delayed report.
Flooding was reported across much of the county with water affecting roads and low lying areas. Numerous secondary roads across the county remain closed with water flowing over them.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Iowa in 2015Every state in 2015This day in weather historyWarnings in Iowa, July 2015
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: 588198, 588202, 588203, 588183, 588191, 588204, 588188, 588196, 588194, 588175, 588197, 588170, 588206, 588146, 588180, 585033, 585061, 588173, 588185, 588186, 588218, 588221, 585217, 588165, 585213, 585209, 593504, 585206, 593505, 585203, 585204, 585210, 588164, 585211, 585205, 585208, 585212, 585219, 585220, 585207, and more.