NWS Forecast Office Tucson, AZ

Although conditions will be quiet through Saturday, things will change as early as Sunday as moisture from a pair of tropical systems makes its way into Southeast Arizona. Initial moisture from these systems will result in a slight chance light showers mainly west of Tucson Sunday. More significant moisture will then push up the Gulf of California into southern Arizona with the assist from Hurricane Polo moving into the southern Baja and northern Mexico Monday and Tuesday. Although we will see deep tropical moisture, it is important to note that the remnants of Polo are NOT expected to impact us directly. A trough of low-pressure moving south along the West Coast the next few days will then track east across Arizona Monday afternoon through Tuesday night. Given the deep moisture in place, this feature will result in widespread showers and thunderstorms across Southeast Arizona. Expect mainly light to moderate intensity rainfall with pockets of heavy rain Monday, with the potential for more widespread moderate to heavy rainfall Tuesday as the front associated with the trough tracks through the area.

Southeast Arizona is in a slight risk of excessive rain both Monday and Tuesday with scattered flash flooding expected.

The most likely timing for rain and thunderstorms will be Monday through Tuesday afternoon.