Flash Flood — St. Charles, Missouri

2022-07-26 · near Foristell, St. Charles, Missouri

Event narrative

Up to 13 inches of rain fell in a 6 to 10 hour period causing widespread flash flooding. The axis of heaviest rain extended from just north of Wentzville east southeastward through northern portions of O'Fallon through St. Peters and into St. Charles. Numerous roads were flooded throughout St. Charles County. Interstate 70 was flooded with up to five feet of water around the intersection with Mid Rivers Mall Drive. Fire and rescue searched and cleared several dozen vehicles in this area and rescued 8 people from the rising waters. Also, in the area of Harry S. Truman Blvd and Premier Parkway, several drivers were rescued from their flooded vehicles. In the area of Mexico Road and Spencer Road, multiple vehicles were trapped by rapidly rising waters of Spencer Creek. One vehicle in this area was swept off the roadway into Spencer Creek. The driver escaped but was clinging to a tree in the fast moving water that was over 8 feet deep. He was rescued and was not injured. Between 1 am and 11 am, 87 people were evacuated from homes or businesses in St. Charles County. One hundred seventeen buildings were damaged from the flooding. Forty Nine of them sustained major damage, 46 sustained moderate damage and 22 buildings sustained minor damage. So far damage is estimated to be around $10 million dollars.

Wider weather episode

During the early morning of Tuesday, July 26th, 2022, a complex of training thunderstorms set up roughly along the I-70 corridor in Missouri and I-64 corridor in Illinois. Several rounds of thunderstorms with rainfall rates exceeding 2in/hr affected this area, including the St. Louis metropolitan area, through the early hours of July 26th and into the morning commute. Upwards of 11 of rain fell over the course of roughly 8 hours in an axis from Hawk Point, MO to St. Peters, MO according to radar-estimated rainfall products and several CoCoRaHS/spotter reports. A longer axis of over 8 of rain fell from northern Montgomery County in Missouri to St. Clair County in Illinois, causing multiple swift water rescues and scores of flooded interstates and homes across the St. Louis metropolitan area. St. Louis-Lambert International Airport also observed a new all-time record for daily precipitation: 8.64 of rain fell since midnight Central Standard Time (Daylight Savings Time is not used for climatological record-keeping). This value broke the previous record of 6.85, which occurred on August 20th, 1915 due to the remnants of the Galveston 1915 Hurricane. The storm-total rainfall was 9.07, but spans two days. Two fatalities were reported: one in St. Louis City, where a man drowned in his car near Skinker Blvd, and another in Hazelwood where a man drowned attempting to flee his flooded truck.

View location on OpenStreetMap → (38.7830, -90.9630)

Source: NOAA Storm Events Database, event_id 1049502. Narrative written by the NWS forecast office that issued the report.