After 1 more day of muggy, sticky conditions, Southern California to get cooler and dryer

Southern California is trading sweltering hot temperatures for muggy and sticky conditions Monday.

The low from what used to be Kay will open up and become a trough and move across the region Monday afternoon. The system will create even more unstable air to our already juice afternoon, so some areas could see a repeat of Sunday's showers and thunderstorms capable of producing heavy downpours and some flooding.

A flood watch begins at 11 a.m. for the mountains and deserts. It remains in effect through Monday evening for the Los Angeles, Ventura County, San Bernardino, and Riverside County mountains. The thunderstorms could bring as much an inch of rain per hour, so flooding is a possibility, and the Inland Empire's rivers, creeks, streams, and other low-lying areas could see excessive runoff.

However, Monday's temperatures will be a welcome break from last week's record heat wave. The valleys and low deserts are expected to reach the low 90s, with upper 70s forecast for the Inland Empire and high deserts. Los Angeles and Orange County's metropolitan areas are looking at 85 degrees, and the beaches could see 79 degrees.

In spite of slight chance of isolated thunderstorms for the mountains and deserts, Southern California's typical dry air will start flowing back into the region Tuesday. A coastal marine influence is also expected to return to Southern California Tuesday night, bringing back near normal temperatures and cooler nights.