Southwest Braces for Flash Flooding as Remnants of Hurricane Priscilla Bring Heavy Rainfall
The remnants of Hurricane Priscilla, combined with a separate weather system, are forecast to bring significant rainfall and a heightened risk of flash flooding to portions of the Southwest through early next week.
Moisture from the former Category 2 hurricane began impacting the region Tuesday, with some severe weather reported yesterday. The National Oceanic and Atmospheric Administration’s (NOAA) Weather Prediction Center (WPC) has issued flash flood alerts for Southern California, northwestern Arizona, and southwestern Utah, currently at a Level 2 out of 4 threat. That threat is escalating, with central Arizona, including the Phoenix area, now under a Level 3 out of 4 flash flood warning. Flood Watches are in effect for cities like Phoenix and Flagstaff, Arizona, and extend to Grand Canyon National Park.
National Weather Service staff warned that “excessive rainfall may result in flooding of slot canyons, normally dry washes, slickrock areas, recent burn scars and other low-lying and flood-prone locations.” Forecasters emphasize that just six inches of fast-moving water can knock an adult off their feet, and a foot of floodwater can sweep away a vehicle. This event is particularly concerning given the ongoing drought conditions across the Western U.S., where over 80% of the region is experiencing unusually dry conditions – a situation that significantly elevates drought risks and wildfire potential.
While the rainfall is not related to the recently concluded monsoon season, it is driven by tropical moisture from the Pacific and a dip in the jet stream. The prolonged wet weather is expected to provide much-needed drought relief and cooler temperatures, with highs dropping from the 90s earlier this week to the 80s. Additional precipitation is anticipated from Invest 90E, which is forecast to become Hurricane Raymond, but that impact is not expected until after the weekend.
Officials are urging residents in affected areas to monitor weather updates and avoid travel through flood-prone areas.
