Sweltering Inland Area to Get Cooling Relief

Temperatures shot past 100 in the El Cajon Valley on Thursday, but inland dwellers who ventured west to the Del Mar Fair found temperatures in the 70s as hazy clouds hugged the San Diego County coastline.

National Weather Service forecasters said a gradual cooling trend will bring temperatures down slightly over the weekend, but hot weather is expected to continue today in the inland valleys, mountains and deserts. Coastal areas should be cooler, although sun-blocking fog will clear partly in the afternoon.

Temperatures Thursday reached 101 in Escondido, 103 in El Cajon, 101 in Santee, 102 in Fallbrook, 94 in Poway, 100 in Campo, 98 in Julian, 82 in Mt. Laguna and 110 in Borrego Springs. Highs reached only 66 in Oceanside, 70 at Cabrillo National Monument and the fairgrounds, 71 in Point Loma, 77 in Coronado and 84 in Chula Vista.

A high-pressure system that generated the high temperatures will weaken over the weekend as falling pressures in the desert intensify. The low pressure is expected to draw in cooler marine air, forecasters said, and increase the bank of low clouds and fog along the coast.

According to forecaster Wilbur Shigehara, thick fog will decrease visibility during night and morning hours along the shore and coastal strip through the weekend. On Thursday visibility at Lindbergh Field was three-eighths of a mile at sunrise, and fog had rolled in again before sunset along Interstate 5.

Fog and low clouds are expected to clear partly to allow some sunshine about noon, and inland area morning clouds are expected to burn off completely for sunny afternoons.

The sub-tropical moisture that raised relative humidity slightly Thursday should dissipate over the weekend.

Temperatures at the beach are expected in the 60s. Coastal strip highs in the 72 to 77 degree range will drop slightly over the weekend, and inland valley highs of 85 to 100 today are expected to range between 77 and 87 Saturday.

Nighttime lows are expected to be in the 60s at the coast and in the 50s inland.