Significant Flood Risk in the Southwest from Tropical Storm Priscilla

The remnants of Tropical Storm Priscilla, which previously reached Category 2 hurricane status, are expected to bring significant rainfall and flash flooding to the Southwestern United States through the weekend. As moisture from Priscilla moves northward, flood watches have been issued for parts of Arizona, California, Nevada, Utah, Colorado, and New Mexico. Rainfall totals are projected to range from 2 to 4 inches, with localized amounts potentially reaching 6 inches in some areas.

NewsweekPacific tropical rainstorms to unleash major flash flooding in southwest USNewsweekForbesCNNTriple Tropical Systems Threaten Severe Flooding in SouthwestNew York TimesThe Cool Down

Central and northern Arizona, particularly the Phoenix metro area, are at the highest risk for flash flooding. The National Weather Service (NWS) has indicated that Phoenix could receive up to 2 inches of rain, significantly higher than its average October rainfall of 0.56 inches. Other areas of concern include southern Utah and southwest Colorado, where similar rainfall amounts are anticipated.

Newsweek

The moisture influx is attributed to the remnants of Priscilla, which has been pulled into a weather system that enhances precipitation across the region. The NWS has noted that the conditions are reminiscent of the flooding caused by Hurricane Rosa in 2018, which resulted in record rainfall in Phoenix. The current weather pattern is expected to continue into early next week, with additional moisture from Tropical Storm Raymond also contributing to the rainfall.

Triple Tropical Systems Threaten Severe Flooding in SouthwestNew York TimesNewsweekLos Angeles MagazineForbesCNNPacific tropical rainstorms to unleash major flash flooding in southwest USNewsweek

Meteorologists have warned residents to prepare for potential flooding, especially in urban areas and regions with recent wildfire burn scars. The NWS has emphasized the dangers of driving through flooded areas, as just 12 inches of water can sweep away vehicles. Local officials are advising residents to stay informed about weather updates and to avoid flood-prone areas.

CNN

Some experts have raised concerns about the increasing frequency and intensity of such weather events, linking them to climate change. They argue that the warming climate is exacerbating the impacts of tropical storms, leading to heavier rainfall and more severe flooding.

The Cool DownCNNLos Angeles MagazineNewsweekPacific tropical rainstorms to unleash major flash flooding in southwest USTriple Tropical Systems Threaten Severe Flooding in SouthwestNBC NewsSacramento BeeNew York TimesForbes

While the NWS has issued flood watches for multiple states, there is some variability in the predicted rainfall amounts. Some forecasts suggest that areas in Arizona could see nearly four times their normal October rainfall, while others indicate more moderate totals. The exact impact of the incoming moisture from Tropical Storm Raymond remains uncertain.

New York Times

As the weekend progresses, residents in the affected areas are urged to remain vigilant. Flood watches will remain in effect, and the heaviest rainfall is expected from Friday night through Saturday morning. Local emergency services are preparing for rapid response to any flooding incidents, and community members are encouraged to have plans in place for potential evacuations if necessary.

Increasing Flood Threat Across the Southwest With Tropical Influence

• “The Weather Prediction Center said the moisture flow that’s expected to set up over Arizona on Friday is similar to the one that occurred in October 2018 when remnants of Hurricane Rosa brought extensive flash flooding to central Arizona.” — Sean Benedict, Meteorologist, Weather Service Office in Phoenix

New York Times

• “Due to the excessive moisture that will be in place, any stronger showers or thunderstorms that do manage to form will be capable of producing moderate to heavy rainfall which may lead to localized flooding,” — National Weather Service, Phoenix Office

The Cool Down

This weather event highlights the ongoing challenges posed by tropical storms in the Southwest, particularly as climate change continues to influence weather patterns. Residents are advised to stay informed and prepared as the situation develops.

Los Angeles Magazine