Story County, IA Environment & Hazard Risk

• DroughtRelatively High$4.32M/yr expected annual loss, about 6.4 events a year
• TornadoRelatively High$10.36M/yr expected annual loss, about once every 2 years
• Winter weatherRelatively High$533K/yr expected annual loss, about 16 events a year
• HailRelatively Moderate$1.78M/yr expected annual loss, about 6.2 events a year
• Strong windRelatively Moderate$1.26M/yr expected annual loss, about 6.1 events a year
• Ice stormRelatively Moderate$209K/yr expected annual loss, about once every 1 year
• LightningRelatively Low$380K/yr expected annual loss, about 43 events a year
• LandslideVery Low$1,118/yr expected annual loss, about once every 14 years
• Cold waveRelatively Low$692K/yr expected annual loss, about 7.8 events a year
• EarthquakeVery Low$142K/yr expected annual loss, about once every 1,629 years
• WildfireVery Low$18.78K/yr expected annual loss, about once every 5,428 years
• HurricaneVery Low$4,522/yr expected annual loss, about once every 100 years
• Heat waveVery Low$37.2K/yr expected annual loss, about 5.4 events a year

Bars show the national percentile score (0 to 100) for each hazard. Dollar figures are expected annual losses to buildings, people and crops. Not rated here: avalanche, coastal flooding, riverine flooding, tsunami, volcanic activity.

Check the flood zone for an address

Homes with flood insurance

95 of 34,139 (0.3%)

Homes in high-risk flood zones

568

Insured in high-risk zones

43 (8%)

Flood claims since 1978

286

Claims paid since 1978

$13.08M

• Thunderstorm Wind343
• Hail293
• Heavy Rain175
• Flood78
• Flash Flood64
• High Wind45
• Tornado31
• Winter Storm31
• Drought27
• Heavy Snow24

• Flood08/11/2010

  Ames, Story County

  $50M damage

  What happened

  Hilton Coliseum reported 4 to 6 feet of water inside flooding the stadium and basketball floor. Cy Stephens Auditorium also reports water in the mechanical building up to the 1st floor.

• Drought07/01/2012

  Story

  $45M damage

  What happened

  Very warm and dry weather that began in the spring continued into the summer. Temperatures warmed sharply the last few days of June. The heat persisted into July. Temperatures for the month of July were among the warmest on record. In Des Moines, the monthly mean temperature was the second highest of record, only eclipsed by July of 1936. Rainfall was in short supply across the state. Much of the state recorded less than 50% of normal rainfall for the month, with a few locations under 10% of normal. In addition, extended periods of temperatures above 95 F resulted in problems with pollination of the crops. Rapid deterioration of the corn and soybean crop took place with several periods of temperatures in excess of 100 degrees. By the end of the month, officials estimated that 20% of the crop yield had been lost to the drought. At the current price, the loss total was in excess of $2.25 billion. As of 31 July, the USDA reported that Secretarial Primary Drought Designations had been listed for 21 counties in the Des Moines CWA, with 11 receiving Contiguous Designation. The primary counties were Butler, Bremer, Hamilton, Hardin, Grundy, Black Hawk, Boone, Story,...

• Drought08/01/2013

  Story

  $21M damage

  What happened

  Serious drought conditions gripped the state through the summer months. Initial sub-soil moisture was good at the beginning of the growing season. The recharged soil was sufficient to maintain the crops through a good part of the summer. Rainfall remained low through August as well and crops deteriorated rapidly under the warmer than normal and very dry conditions. Rainfall for the summer was between 1/3 and 2/3rds of normal across much of the Des Moines CWA. A large part of the CWA received under 5% of normal rainfall in August, with most areas under 20%. Crop loss through the month was around 10%. This translated to over $600 million in crop loss for the corn crop, and about $350 million for soybeans.

• Flood06/12/2010

  Story City, Story County

  $20M damage

  What happened

  Heavy rainfall during the month of June caused considerable crop losses across the state. Crop damage was done through a combination of inundation flooding and losses due to crops not being able to be planted or rotting in the ground. It is not possible to get a clear breakdown of the percent of damage that can be attributed to each cause. The damage here is not related to the river flooding. Those flooding events are addressed in other flooding entries. Many of the southern Iowa counties were unable to plant crops at all through June, while areas of the central and north lost the crops that were planted through drowning or washouts. Estimates from the state and county extension offices indicated that about 10% of the crop was lost across the state. The amount of loss in the DMX CWA was around $1 billion to the corn and soybean crop. By the end of the month, Iowa Governor Culver declared 32 counties state disaster areas. They were Black Hawk, Buena Vista, Butler, Cherokee, Clay, Davis, Decatur, Emmet, Franklin, Hamilton, Hancock, Howard, Humboldt, Jasper, Jefferson, Kossuth, Lee, Lyon, Mahaska, Madison, Marion, Monroe, O'Brien, Osceola, Palo Alto, Polk, Ringgold,...

• Drought08/01/2003

  Story

  $12.65M damage

  What happened

  Dry weather settled in over Iowa during the month. The last widespread rain occurred on 09 July. With the increasingly dry conditions became a primary concern as the month progressed. An extended period of heat and humidity from the 15th to 25th saw highs into the 90s to over 100 degrees F. in some locations. By month's end drought indices had worsened to severe to extreme drought across south central Iowa and at least moderate drought over the remainder of the HSA. Waterloo had its driest August on record, Des Moines its 3rd driest and Ottumwa its 8th driest. A cold front brought only a brief respite from the intense heat, as temperatures rebounded into the 90s to near 100 degrees F. on the 24-26th. Des Moines Airport reached the century mark for the first time since July 29, 1999, reaching 100 F. on the 24th and 101 F. on the 25th. This was followed by a slow cool down as several pushes of cooler air traversed the state. Unfortunately there was only widely scattered convection across the HSA on the 27th and 28th, providing little significant drought relief. Light to moderate rainfall on the 31st fell across primarily the southern one half of the HSA, with the heaviest...

• Drought08/01/2001

  Story

  $11.35M damage

  What happened

  In what became a rather tough growing season, drought developed in Iowa during the month of July, and became serious in August. During the early part of the growing season, excessive rainfall caused significant planting delays across the state. Once the crop was planted, cool and cloudy weather settled into the state slowing crop maturation. Once the warm weather finally arrived, rainfall tailed off significantly. Very little rainfall was reported during the month of July, however crops flourished with the moisture that was available. During the last half of July, temperatures began to soar into the 90s quite regularly. Temperatures were in the 90s to around 100 for most of the first 10 to 12 days of August with virtually no rainfall. Moisture reserves ran out during the critical time of pod filling for the soybeans and at the tasseling for the corn. Another factor that complicated the situation was the soil moisture profile over central and southwest Iowa. After two years of drought, rain began falling during the last fall of 2000 and continued into the spring of 2001. Though soil moisture was replenished in part, a layer of dry soil remained below the moistened...

• Heavy Snow02/20/2026

  Story

• Thunderstorm Wind50 kt wind09/23/2025

  Ames, Story County

• Thunderstorm Wind51 kt wind07/19/2025

  Iowa Center, Story County

• Thunderstorm Wind50 kt wind07/19/2025

  Nevada, Story County

• Thunderstorm Wind52 kt wind07/19/2025

  Nevada, Story County

• Thunderstorm Wind62 kt wind07/19/2025

  Gilbert, Story County

• Tornado2.19 mi path, 40 yd wide07/19/2025

  Gilbert, Story County

• Hail0.75" hail06/20/2025

  Ames, Story County

• Ames Water Treatment PlantServes 55,177 · Groundwater · Local governmentNo health violations+1 monitoring or reporting
• IsuServes 42,000 · Purchased groundwater · StateNo health violations+1 monitoring or reporting
• Ia Regional Utilities Assoc (Waverly)Serves 37,820 · Groundwater · PrivateNo health violations
• Nevada Water SupplyServes 6,925 · Groundwater · Local governmentNo health violations
• Huxley Waterworks DeptServes 4,244 · Groundwater · Local governmentNo health violations
• Story City Water DeptServes 3,357 · Groundwater · Local governmentNo health violations+3 monitoring or reporting
• Slater Muni Water DeptServes 1,548 · Purchased groundwater · Local government1 health violation+3 monitoring or reporting
• Roland Water SupplyServes 1,394 · Groundwater · Local governmentNo health violations