Topline
The Southwest U.S. will face “significant risk” of heavy rains and flash flooding as the remnants of Tropical Storm Priscilla—downgraded from a Category 2 hurricane—is expected to pass through the region over the weekend, weather officials warned on Friday.
According to the National Hurricane Center’s Friday morning update, Priscilla has continued to weaken in intensity and it is expected to become a post-tropical remnant later in the day before dissipating on Saturday.
However, the moisture-laden remnants of the storm could bring between 2 to 4 inches of rain across parts of central and northern Arizona, southern Utah, and southwest Colorado through Saturday—with some local instances as high as 6 inches.
The heavy rains could trigger flash flooding in central Arizona and southwest Utah, with “scattered areas of flash flooding expected across the remainder of Arizona, southern Utah, southwest Colorado, and far northwest New Mexico," the hurricane center warned.
In a separate update, the National Weather Service warned “ many streams may flood, potentially affecting larger rivers,” and the flooding could trigger debris flows in and around areas recently impacted by wildfires.
The Associated Press noted Priscilla’s remnants could bring as much downpour in hours as some of these areas receive all year, elevating the risk of flash flooding.
Tropical Storm Raymond, named earlier on Thursday, is the third such system to have formed off of Mexico’s Pacific coast this week after Priscilla and Octave. The NHC reported maximum sustained winds of 60 mph with higher gusts on Friday morning and the storm is expected to move parallel to the southwestern coast of Mexico on Friday. While Raymond is likely to weaken over the weekend, moisture from Raymond’s remnants “also bring the potential for additional heavy rainfall over portions of the Southwest U.S. early next week,” the NHC said.