A huge system of high pressure is starting to settle over the southwestern United States — and that’s expected to produce record heat in parts of San Diego County and spotty, dense fog at the coast, according to the National Weather Service.

Forecasters said Chula Vista’s high could hit 81 degrees on Friday, which would set a record for June 16 by two degrees. The average high for that day of the year in Chula Vista is 69 degrees.

El Cajon’s daytime high is expected to reach 94 degrees on Friday, which would break the record by one degree and soar above the average of 82.

Temperature records also could be set in the mountains and desert next week.


It appears that temperatures will be in the 68- to 70-degree range early Saturday during commencement at UC San Diego. Patches of morning fog could drift across the university, where a crowd is expected for the Dalai Lama’s graduation address.

This kind of come-and-go fog could afflict beaches until early next week, possibly spreading east of Interstate 5.

Meteorologists predict the heat wave will intensify Sunday and Monday. Temperatures could ascend to the 118- to 120-degree range in the Borrego Springs-Ocotillo Wells area. An excessive heat warning will be in effect for those locations.

Looking north, Palomar Mountain could reach 85 degrees on Friday and 98 on Tuesday, which would set a record for the date. The average high for Palomar Mountain on June 20 is 80 degrees.


Temperatures will be in the 90s and relative humidity will fall to single digits across many other inland areas. But the weather service doesn’t plan to issue a fire-weather warning because winds will be light. It’s still possible that wildfires could break out across the region.

Sea-surface temperatures have warmed up a bit, to the 64- to 66-degree range. The surf will be in the 2- to 3-foot range at most beaches during this weekend. And dangerous rip currents are possible along the region’s entire coastline.

The summer solstice will occur at 9:24 p.m. Tuesday (June 20).


Twitter: @grobbins

gary.robbins@sduniontribune.com