SERIOUS FLOODING FOR THE SOUTHWEST AND PLAINS

Impacts and timing

Our attention turns to Hurricane Polo, which is forecast to move into Baja and eventually north into New Mexico. Beginning tomorrow, heavy rain will spread across Arizona, New Mexico, Utah, and Colorado, then push into the central Plains, including Kansas and Nebraska. The rain will continue to move through the Plains Tuesday into Wednesday, with flooding possible as far north as Iowa.

Across parts of the region, rainfall totals over the next two days could reach 4 to 6 inches. That amount brings a serious flooding risk, especially in Arizona and New Mexico. Flooding in desert areas could become life-threatening. Tropical moisture moving into the desert Southwest can produce fast-developing flooding, including dangerous flash flooding.

Utah also faces a flash-flood risk. Heavy rain could send water down canyon areas near Moab and Bryce Canyon, where flooding may develop quickly. Farther east, rain could cause flooding across Kansas, with the risk possibly extending into Iowa as the system moves through Tuesday and Wednesday.

Bottom line

The greatest stated concern is serious, potentially life-threatening flooding in Arizona and New Mexico, along with fast flash flooding in Utah’s canyon areas. Flooding is also possible across the Plains, especially in Kansas, and perhaps into Iowa Tuesday into Wednesday.