| July 1994 | Thunderstorm Wind | Delaware | 1 hurt, $5,000 | Trees and limbs were downed, at least one falling on a house. Outbuildings were damaged. A 36 year-old man had to be hospitalized after lightning hit the barn he was in as he sat in a metal chair. |
| July 1996 | Lightning | Delaware | $620,000 | no account filed |
| June 2004 | Flash Flood | Delaware | $250,000 | As much as five inches of rain caused severe flooding in and around Delaware. 154 homes were damaged, many in subdivisions along State Route 257 northwest of Powell. 34 mobile homes in the Shroyers Mobile Home Park just north of Delaware sustained damage when the Olentangy River rose out of its banks, and forced a few evacuations. Numerous roads and bridges were damaged by high water and culvert washouts. |
| May 1997 | Thunderstorm Wind | Delaware | $100,000 | Numerous trees downed. Six homes were damaged when trees fell on them. |
| June 2022 | Thunderstorm Wind | Delaware | $50,000 | Numerous trees and power lines were downed throughout Delaware County. |
| April 2014 | Thunderstorm Wind | Delaware | $25,000 | A roof was blown off of a structure in Delaware due to thunderstorm winds. |
| July 2013 | Thunderstorm Wind | Delaware | $25,000 | Several large trees were downed due to thunderstorm winds. A dugout collapsed at Delaware Christian sporting fields. |
| August 2016 | Tornado (EF0) | Delaware | $20,000 | A weak tornado initially touched down just south of the Buckeye|Valley Middle School. The damage near the school was limited to|one tree with a limb down. The track continued north-northeast|into a residential area. In this residential area several 2 to 4|inch limbs were snapped and a few shallow-rooted trees were|uprooted. Roof damage was observed due to a fallen tree on Coover|Road and a barn had part of the roof cave in on its east side.||The tornado lifted until it crossed US-23 just west of Delaware|Dam. A small cluster of trees were twisted on the west side of the|highway.||The next location is Delaware State Park where the tornado was on|the ground for a few minutes. At Delaware State Park, a few|partially rotten large limbs were downed and numerous 2 to 3 inch|limbs were also downed. Also, several shallow rooted trees were|uprooted. A medium-sized dumpster near the marina was tipped and|moved about 20 feet. Three boats at the marina sustained minor|awning damage. A few 2 to 3 inch tree limbs around the marina were|snapped. Across the river from the marina, a snapped limb marked|the end of the tornado track. |
| September 2011 | Thunderstorm Wind | Delaware | $20,000 | A two to three foot diameter tree was reported down. Several tree limbs fell on cars. Railroad crossing arm guard equipment was damaged. These occurrences were due to damaging thunderstorm winds. |
| July 1997 | Thunderstorm Wind | Delaware | $20,000 | Roof peeled off a barn and numerous trees downed. |
| August 2010 | Thunderstorm Wind | Delaware | $15,000 | Two tractor trailers were blown over and shingles were ripped off of a house due to damaging thunderstorm winds. |
| September 2020 | Thunderstorm Wind | Delaware | $10,000 | Several trees and wires were downed in and near the city of Delaware. |
| June 2012 | Thunderstorm Wind | Delaware | $10,000 | Trees and power lines were downed due to damaging thunderstorm winds. |
| July 2012 | Thunderstorm Wind | Delaware | $10,000 | There were numerous reports of downed trees in Delaware County due to damaging thunderstorm winds. |
| May 2004 | Hail | Delaware | $10,000 | Trees were also knocked down near the intersection of State Route 37 and Houk Road. |
| July 2023 | Thunderstorm Wind | Delaware | $8,000 | Several trees were downed across mainly western portions of Delaware County. |
| January 2008 | Thunderstorm Wind | Delaware | $8,000 | A street lamp was blown down. A house sustained siding damage and had roof shingles peeled off in the same neighborhood. |
| June 2006 | Thunderstorm Wind | Delaware | $8,000 | Several tents were blown down at the Delaware County Fairgrounds. Trees were also downed. |
| June 2025 | Thunderstorm Wind | Delaware | $6,000 | Several trees were downed in Delaware as well as in Concord Township. |
| August 2003 | Thunderstorm Wind | Delaware | $6,000 | Several trees up to twelve inches in diameter were knocked down across the southern and central portions of the county. |
| August 2025 | Thunderstorm Wind | Delaware | $5,000 | Several trees were downed in the city of Delaware, including in Mingo Park. |
| August 2019 | Thunderstorm Wind | Delaware | $5,000 | Trees and power lines were knocked down. |
| June 2016 | Flash Flood | Delaware | $5,000 | There were numerous reports in the city of Delaware of roads closed due to high water. The city had high water throughout. |
| June 2013 | Thunderstorm Wind | Delaware | $5,000 | There were several reports of trees down around Delaware County due to thunderstorm winds. |
| April 2006 | Thunderstorm Wind | Delaware | $5,000 | Tiles were blown off the roof of a building in town. |
| July 2003 | Thunderstorm Wind | Delaware | $5,000 | Numerous trees and powerlines downed. |
| July 2000 | Thunderstorm Wind | Delaware | $5,000 | Trees and power lines downed. |
| July 1997 | Thunderstorm Wind | Delaware | $5,000 | Several trees downed. |
| June 1994 | Thunderstorm Wind | Delaware | $5,000 | Trees were downed. |
| August 1994 | Thunderstorm Wind | Delaware | $5,000 | Large hail fell in Delaware and winds were reported at 75 mph in Ashley. Trees were downed in both locations. |
| July 1994 | Hail | Delaware | $5,000 | no account filed |
| July 2023 | Thunderstorm Wind | Delaware | $4,000 | A few trees were downed along U.S. 23 in Delaware. |
| August 2020 | Thunderstorm Wind | Delaware | $4,000 | Several trees were reported knocked down throughout the county. |
| June 2009 | Thunderstorm Wind | Delaware | $4,000 | An awning over a gas station collapsed. |
| June 2020 | Thunderstorm Wind | Delaware | $3,000 | Wires were knocked down at multiple locations. |
| August 2019 | Thunderstorm Wind | Delaware | $3,000 | Several large trees were knocked down in Mingo Park. |
| June 2012 | Thunderstorm Wind | Delaware | $3,000 | Trees were down along Curve Road due to damaging thunderstorm winds. |
| February 2009 | Thunderstorm Wind | Delaware | $3,000 | Trees were downed. |
| July 2008 | Thunderstorm Wind | Delaware | $3,000 | Twelve to fifteen large tree limbs were downed across the Ohio Wesleyan University campus. |
| September 2003 | Thunderstorm Wind | Delaware | $3,000 | A few trees and a power pole were downed. |
| June 2010 | Thunderstorm Wind | Delaware | $2,000 | There were multiple reports of trees down from gust front winds. |
| May 2007 | Thunderstorm Wind | Delaware | $2,000 | Large tree limbs were downed. |
| June 2007 | Thunderstorm Wind | Delaware | $2,000 | Large tree limbs were knocked down. |
| June 2004 | Thunderstorm Wind | Delaware | $2,000 | Two trees were downed. |
| November 2002 | Thunderstorm Wind | Delaware | $2,000 | Powerlines were knocked down. |
| November 2017 | Thunderstorm Wind | Delaware | $1,000 | A tree was downed along River Street. |
| June 2015 | Thunderstorm Wind | Delaware | $1,000 | One tree was knocked down. |
| June 2010 | Thunderstorm Wind | Delaware | $1,000 | Several five inch diameter trees snapped in half at their trunks. |
| May 2007 | Hail | Delaware | $1,000 | no account filed |
| July 2022 | Thunderstorm Wind | Delaware | $200 | A 4 inch diameter tree was downed. |
| June 2016 | Thunderstorm Wind | Delaware | $100 | A two to three inch diameter tree branch broken from tree. Pea size hail also was reported, along with visibilities reduced to less than half a mile. |
| May 2020 | Flood | Delaware | - | Northbound U.S. 42 was closed at Shortcut Road due to high water. |
| September 2020 | Thunderstorm Wind | Delaware | - | The wind gust was measured on the EMA weather station at the county courthouse. |
| July 2019 | Flood | Delaware | - | High water was reported on Central Avenue. |
| July 2019 | Flood | Delaware | - | Troy Road was closed south of Smith Park due to high water. |
| May 2018 | Flood | Delaware | - | High water was reported on several streets in the city of Delaware. |
| November 2017 | Flash Flood | Delaware | - | High water was reported over a portion of State Route 521. |
| November 2017 | Flash Flood | Delaware | - | High water was reported throughout the city of Delaware with several roads closed. |
| November 2017 | Flood | Delaware | - | About an inch of water was reported on a few roads in the Delaware area. |
| May 2016 | Hail | Delaware | - | Penny to half dollar size hail fell across the Delaware area. |