Patchy low clouds and dense fog were predicted to quickly erode toward the San Diego County coast Saturday, the National Weather Service said.
Warming conditions were likely through early next week, with highs topping out 5 to 12 degrees above normal by Sunday.
Subtle increases in moisture aloft were expected to lead to increased mid-level cloud coverage and a slight chance of showers and isolated thunderstorms across the southern mountains and lower deserts on Monday.
Cooler conditions will develop late next week, forecasters said.
On Friday, the NWS said Escondido and El Cajon tied the highest minimum temperature records, both at 65 degrees.
High temperatures along the coast Saturday were predicted to be 73 to 78 degrees with overnight lows of 59 to 64. Highs in the western valleys were expected to be 86 to 91, and 94-99 near the foothills with overnight lows of 61- 67. Highs in the mountains were expected to be 90 to 98 with overnight lows of 60 to 70, and highs in the deserts were predicted to be 110 to 115 with overnight lows of 77 to 85.
Hot and dry weather was expected through early next week inland, while sea breezes moderate coastal areas each day.
Some increase in humidity was expected by Monday, but it likely will remain quite hot, with gusty late day and evening winds below passes and canyons. The chance for any thunderstorms was very small Monday and Tuesday, but could result in a few dry lightning strikes.
Temperatures were predicted to be above average through midweek, then back to about average Thursday and continuing to fall into the July 4th holiday weekend.
The combination of heat, gusty winds, and low afternoon humidity was expected to keep elevated fire weather conditions on the desert mountain slopes and into the deserts for a few hours each day.
— City News Service