| August 1996 | Thunderstorm Wind | Washington | 3 killed, 6 hurt | no account filed |
| August 2012 | Thunderstorm Wind | Washington | 2 hurt | Thunderstorm winds caused widespread tree and power line damage across Washington. Two people sustained minor injuries from flying debris in the parking lot of the Washington Town and Country Fair. Also, several tents were blown down. Fortunately, the fair grounds had been evacuated. |
| June 2005 | Thunderstorm Wind | Washington | 2 hurt | no account filed |
| April 1994 | Thunderstorm Wind | Washington | $50,000 | County officials reported roof damage to various homes in Washington. Several sheds and part of the fire department roof was damaged in Union. A radio station also sustained tower damage and was off the air for a period of time. |
| September 1993 | Tornado (F0) | Washington | $50,000 | A tornado produced a 2-mile-track of minor damage to a few homes and trees southwest of Washington along County Road A. Damage was mainly to roofs and was not continuous. |
| April 2024 | Thunderstorm Wind | Washington | $30,000 | There were reports of multiple downed trees and large branches in Washington impacting homes and power lines. AWOS at Washington Regional Airport reported a 72 mph gust at the time. |
| July 2007 | Thunderstorm Wind | Washington | $10,000 | Thunderstorm winds caused scattered tree damage in Washington. A large tree limb fell on a house on West Fourth Street causing some roof damage. Several trees and large limbs were downed along the Rotary Riverfront Trail. |
| October 2001 | Thunderstorm Wind | Washington | $10,000 | no account filed |
| August 2021 | Thunderstorm Wind | Washington | $3,000 | Thunderstorm winds blew down several trees and tree limbs. |
| June 2022 | Thunderstorm Wind | Washington | $1,000 | Thunderstorm winds damaged a small shed. |
| May 2025 | Hail | Washington | - | A Washington School District official submitted a photo of half dollar size hail. |
| April 2025 | Flash Flood | Washington | - | The Department of Highways and the public reported multiple inaccessible roads in Franklin County due to flooding. These include parts of Highway A and Highway YY due to side ditches overflowing and Highway CC due to Big Creek flooding over the road and onto the other side. Notably, this is a low point on the highway. On April 5th, the Missouri Department of Transportation reported that Route W just past Sand Ford Road at the entrance to Meramec Caverns was closing due to flooding of the Meramec River. Franklin County received up to 6.2 inches of rain during this event. |
| August 2025 | Thunderstorm Wind | Washington | - | Thunderstorm winds downed numerous tree limbs 12 to 18 inches in diameter. A few trees were downed in an area from Grand Ave to Jefferson Ave north of 5th Street. |
| April 2021 | Thunderstorm Wind | Washington | - | Thunderstorm winds snapped off a large tree limb. The tree limb landed on power lines, knocking out the power to a large portion of town. |
| September 2021 | Thunderstorm Wind | Washington | - | Thunderstorm winds blew down numerous large tree limbs. |
| October 2018 | Thunderstorm Wind | Washington | - | Thunderstorm winds blew down two large trees in town. |
| April 2016 | Thunderstorm Wind | Washington | - | A couple of large tree limbs were blown down. |
| February 2011 | Thunderstorm Wind | Washington | - | Thunderstorm winds blew down numerous large trees, tree limbs and power lines throughout town. A couple of businesses sustained minor to moderate roof damage when sections of their roofs were blown off. Some of the fallen trees landed on homes and vehicles causing minor to moderate damage. A section of bleachers at the Washington Fairgrounds were folded over. |
| July 2010 | Thunderstorm Wind | Washington | - | Thunderstorm winds blew down a large tree in Washington. It caused minor roof damage to a nearby house. |
| July 2010 | Thunderstorm Wind | Washington | - | Thunderstorm winds blew down numerous large tree limbs around town. One large tree limb fell onto power lines and knocking them down. |
| July 2009 | Thunderstorm Wind | Washington | - | Several large tree limbs and a power line were blown down in town. |
| September 2009 | Flash Flood | Washington | - | Between 3 and 5 inches of rain fell in a short amount of time over Franklin county causing flash flooding. Several roads were flooded including roads near the city park in Union and roads in the Washington area. |
| March 2009 | Thunderstorm Wind | Washington | - | Thunderstorm winds blew down a large tree onto a house in town causing minor damage. Also, a couple of large trees and several large tree limbs were blown down. Two billboards and a couple of power lines were blown down and part of the roof of a business was blown off. The roof of a church sustained minor damage due to the thunderstorm winds. |
| July 2008 | Thunderstorm Wind | Washington | - | Thunderstorm winds blew down several large tree limbs in Washington. One large tree limb damaged three fences as it fell to the ground. |
| July 2007 | Thunderstorm Wind | Washington | - | Local law enforcement reported several large tree limbs down on the south side of town. |
| August 2007 | Thunderstorm Wind | Washington | - | Numerous tree limbs were blown down. Also, several trees and power lines were blown down on Highway V near Highway 100. |
| January 2006 | Hail | Washington | - | A storm spotter reported 1 inch hail southwest of Washington. |
| April 2006 | Hail | Washington | - | Local law enforcement reported 3/4 inch hail. |
| June 2006 | Thunderstorm Wind | Washington | - | Several large tree limbs were blown down onto Highway 100. |
| July 2006 | Thunderstorm Wind | Washington | - | Numerous trees, tree limbs and power lines were blown down. |
| June 2005 | Thunderstorm Wind | Washington | - | A sudden severe thunderstorm took down trees, large tree limbs, and power lines in Washington. At least two homes had large tree limbs fall on them causing minor damage. Several power lines were downed by trees causing at least 3000 people to lose power. A lightning strike knocked down a 34,000 volt electric line causing rain water to boil in the street. |
| June 2005 | Thunderstorm Wind | Washington | - | Amateur radio spotters reported trees down in a city park. |
| May 2004 | Hail | Washington | - | Storm spotters reported 1 inch hail. |
| May 2004 | Hail | Washington | - | Storm spotters reported 3/4 inch hail. |
| July 2004 | Hail | Washington | - | Amateur radio spotters reported 3/4 inch hail. |
| May 2002 | Thunderstorm Wind | Washington | - | Thunderstorm wind gusts blew over a large tree damaging a home in Washington. The roof and side of the home was damaged, as was a fence and a parked camper. |
| August 2001 | Thunderstorm Wind | Washington | - | The Washington Police reported trees and power lines down just west of town. |
| April 1993 | Hail | Washington | - | Ham radio operators reported 0.75-inch-diameter hail. |
| May 2025 | Hail | Washington | - | no account filed |
| May 2025 | Hail | Washington | - | no account filed |
| May 2025 | Hail | Washington | - | no account filed |
| May 2024 | Hail | Washington | - | no account filed |
| April 2018 | Hail | Washington | - | no account filed |
| June 2013 | Hail | Washington | - | no account filed |
| May 2013 | Hail | Washington | - | no account filed |
| April 2011 | Hail | Washington | - | no account filed |
| April 2011 | Hail | Washington | - | no account filed |
| April 2011 | Hail | Washington | - | no account filed |
| March 2009 | Hail | Washington | - | no account filed |
| February 2008 | Hail | Washington | - | no account filed |
| January 2008 | Hail | Washington | - | no account filed |
| March 2008 | Hail | Washington | - | no account filed |
| March 2006 | Thunderstorm Wind | Washington | - | no account filed |
| March 2006 | Hail | Washington | - | no account filed |
| April 2006 | Hail | Washington | - | no account filed |
| September 2005 | Thunderstorm Wind | Washington | - | no account filed |
| August 2005 | Thunderstorm Wind | Washington | - | no account filed |
| May 2004 | Hail | Washington | - | no account filed |
| May 2004 | Hail | Washington | - | no account filed |
| May 2004 | Hail | Washington | - | no account filed |