The connection between thunderstorms and flash flooding

11/30/2020 (Permalink)

In the Pacific Northwest, thunderstorms can be familiar. However, it’s important to be aware of how they can be dangerous, and how you can be prepared. Here at SERVPRO of Northwest Portland, we wanted to share some vital information on how thunderstorms and dangerous flash flooding are connected.

Most flash floods are caused by slow moving thunderstorms, often ones that move repeatedly over the same area, or heavy rains from tropical storms and hurricanes. Tropical storms don’t often make their way to the Pacific Northwest because of the cooler temperature in the Pacific Ocean, however we are no stranger to severe stormy weather.

Flash floods can develop within minutes, but can also take hours - it depends on the intensity and duration of the rain, the topography of the area, the soil conditions and the ground cover. Staying tuned in to the weather service and NOAA can help you stay informed during heavy rain events and storms.

Once a flash flood develops, it becomes a force to be reckoned with. Flash floods can roll boulders, tear out trees, destroy buildings and bridges, and scour out new channels. Flood-producing rains can also trigger secondary events, such as landslides and mudslides. 

If sudden heavy rain and rising standing water happens near you, it’s advised that you avoid them if you can. If you are driving, the safest option is to pull over, turn on your hazard lights, and wait out the heavy rain conditions until the road is safer. 

To read more about thunderstorm safety and flood safety, visit Ready.Gov.

No matter the storm event, SERVPRO of Northwest Portland is ready to respond to the area for storm response restoration and repairs. Once you are safe and ready to receive service, call us at 503-283-3658.

Sources: weather.gov