Weekend Beachgoers Will Face a Delay in Starting Their Tans

A ridge of high pressure that has settled along the Southern California coast should keep beachgoers waiting until late morning or afternoon for sunshine this weekend, but mountain and desert weather should be sunny and warm, the National Weather Service said Thursday.

The temperature at Los Angeles Civic Center peaked at 80 degrees Thursday, with relative humidity ranging from 78% to 43%. The forecast called for a gradual warming trend continuing through the early part of next week.

Relative humidity was expected to stay above 50% almost everywhere, except in the deserts. This was especially good news for firefighters, who know that an influx of hot, dry air can be a prelude to disaster in this part of the world.

Brush Fire Threat

Capt. Gordon Pearson, public information officer for the Los Angeles County Fire Department, said this summer promises to be exceptionally hazardous for areas subject to brush fires.

Rainfall thus far in 1985, he said, has been substantially lighter than usual (2.03 inches below normal, so far) while the amount of dead brush--including sumac, ceaonthus and manzanita--has increased substantially since last year, in some cases totaling as much as 40 tons to the acre.

And to top it all, Pearson said, the weather service has issued a prediction of higher temperatures this summer, with humidity levels dropping into the teens.

In addition, the captain said, there has been a high incidence of fires caused by arson.

For 1984, he said, 2,259 of the 2,390 grass and brush fires reported in the county--well over 90%--were officially designated as being of suspicious origin.

Meanwhile, forecasters said humidity should remain high for a while, especially along the coast, where surfers on south-facing beaches may continue to benefit throughout the weekend from a Southern Hemisphere hurricane that is offering breaker sets to four and six feet.

Weekend sailors can expect west to northwest winds to 15 knots, with combined seas to six feet in outer waters.

Temperatures were expected to reach the upper 70s and lower 80s in the San Gabriel and San Bernardino mountains and in the Sierra.

Westerly winds to 35 m.p.h. were also predicted for the deserts, where fair skies were expected to produce afternoon temperatures in the high 90s to 106 degrees in the northern desert, with the southern desert about 10 degrees hotter.

Vegas Thundershowers

Las Vegas and southern Nevada also were told to look for possible thundershowers by Sunday afternoon, with a cooling trend holding temperatures to the upper 90s and below.

San Francisco’s weekend was, as usual, expected to include variable coastal fog and low clouds, but afternoons were expected to see fair skies, with highs from the mid-60s to mid-70s near the coast ranging upward to above 100 degrees in the San Joaquin Valley.