Moderate Flash Flood Threat Hits Four Corners Sunday After Arizona Rains Tonight

On Saturday, October 31st, into early Sunday, November 1st, a Slight risk of excessive rainfall covers portions of central Arizona. Most places stay dry during the day, but the real rain arrives tonight as moisture streams in from the southwest and focuses over the Mogollon Rim. Soils there are already soaked from recent heavy rains, so scattered flash flooding is possible on low water crossings, small creeks, city streets, and burn scars. Surrounding areas including much of Nevada and the Sierra foothills carry a Marginal risk, where 1 to 3 inches of rain could bring isolated flooding in river valleys. Slot canyons in southern Utah and mountain ranges in southern California also face isolated concerns. Never drive through flooded roads. Elsewhere, only a low Marginal risk exists from the lower Mississippi Valley to the Gulf Coast and across east and southeast Florida, where any flooding would be isolated and limited.

On Sunday, November 1st, into early Monday, November 2nd, a Moderate risk of excessive rainfall covers portions of the Four Corners region. The moisture stream continues across the Southwest and drives heavy rain into the Mogollon Rim of central Arizona and then the San Juan Mountains of southwest Colorado. Soils remain wet from a recent high-impact flood event and smaller rains since, so flash flooding is likely. Widespread 3-inch totals are expected north and east of Phoenix with locally higher amounts that will run off quickly. The Moderate risk expands north in Utah along the I-15 corridor to include large burn scars near the I-15 and I-70 junction, where 1 to 2 inches of rain can trigger flash flooding. A Slight risk reaches the Salt Lake City area because of urban concerns from nearby mountains. Avoid low water crossings, slot canyons, and flooded roads as the heaviest rain moves through and then eases.

Also on Sunday, November 1st, into early Monday, November 2nd, a Slight risk of excessive rainfall stretches along the east coast of Florida through the Jacksonville metro. Tropical moisture brings widespread rain across the peninsula while east-coast soils stay saturated from several days of earlier rainfall. This favors widely scattered flooding, especially in urban and low-lying areas. A small Marginal risk shifts northward over parts of Kansas and eastern Nebraska, but soils there can absorb most of the rain and rates stay modest, keeping any flooding limited and low-end. Stay clear of rising water on streets and never drive through flooded roads.

On Monday, November 2nd, into early Tuesday, November 3rd, a Slight risk of excessive rainfall continues for the east coast of Florida along the full I-95 corridor. Heavy rain potential remains over the same already-saturated ground, so scattered flash flooding is still possible in urban spots and low-lying places. The threat stays focused on that coastal strip while most other regions see little flooding concern.

On Tuesday, November 3rd, into early Wednesday, November 4th, a Marginal risk of excessive rainfall covers portions of the Southern Plains and mid and lower Mississippi Valley to the Tennessee Valley, then extends from the Tennessee and lower Ohio Valleys to the southern Appalachians. Isolated flash flooding is possible where heavier showers develop, mainly on low water crossings, small creeks, and spots with poor drainage. The overall threat remains low and gradually eases as the system moves along.