June Gloom to Persist Through the Week

June gloom conditions will dominate Southern California weather through the week with daily marine layer intrusions and below-normal temperatures before a warming trend develops by weekend, the National Weather Service said Monday.

Forecasters predict maximum temperatures will remain below normal through Thursday as night and morning low clouds and fog occur daily across coastal and valley areas. A gradual warming trend will begin Friday.

The marine layer showed limited reach early Monday morning with most of Los Angeles County remaining cloud-free. Satellite imagery indicated stratus clouds moving through Orange County that should bring low clouds to the L.A. County coast and portions of the San Gabriel Valley by dawn Tuesday.

Tuesday will feature the most significant weather activity of the week. An upper low pressure system will deepen the marine layer and likely produce areas of drizzle in morning hours. The system may trigger isolated thunderstorms over Los Angeles and Ventura county mountains during afternoon and evening hours.

Gusty onshore winds will accompany the system Tuesday, with speeds reaching 25 to 40 mph across interior areas. The Antelope Valley foothills could see gusts up to 45 mph.

The upper low will linger Tuesday evening and bring a chance of showers to the L.A. mountains and Antelope Valley before exiting the region early Wednesday.

Wednesday morning may see scattered showers in eastern Los Angeles County as moisture wraps around the departing system. Another round of gusty west winds is forecast for the Antelope Valley.

Temperatures will begin climbing Thursday as the upper low exits and high pressure builds over the region. Weekend highs will rise to above-normal levels with mostly clear skies expected.

Monday’s forecast calls for sunny conditions with highs near 77 degrees and southeast winds of 5 to 10 mph. Patchy drizzle and fog will develop Monday night with increasing clouds.

By Saturday, sunny skies will return with highs reaching 83 degrees. Sunday will see similar conditions with temperatures near 82 degrees and mostly clear overnight conditions.

The weather service said the pattern reflects typical June gloom characteristics for Southern California, with marine layer influence gradually diminishing as inland high pressure strengthens later in the week.

Here is the latest forecast for Pasadena from the National Weather Service as of 4:19 a.m. on Monday, June 2.

Monday: Sunny, with a high near 77. Southeast wind 5 to 10 mph becoming south southwest in the afternoon.

Monday Night: Patchy drizzle and fog after 11:00 p.m. Increasing clouds, with a low around 58. South southwest wind 5 to 10 mph becoming light south after midnight.

Tuesday: Patchy drizzle and fog before 11:00 a.m. Cloudy through mid morning, then gradual clearing, with a high near 77. Light south wind becoming southwest 5 to 10 mph in the afternoon.

Tuesday Night: Partly cloudy, with a low around 57. Southwest wind 5 to 10 mph becoming light south in the evening.

Wednesday: Patchy fog before 11:00 a.m. Otherwise, partly sunny, with a high near 76.

Wednesday Night: Patchy fog after 11:00 p/m. Otherwise, mostly cloudy, with a low around 58.

Thursday: Patchy fog before 11:00 a.m. Otherwise, mostly sunny, with a high near 79.

Thursday Night: Mostly clear, with a low around 59.

Friday: Sunny, with a high near 81.

Friday Night: Mostly clear, with a low around 60.

Saturday: Sunny, with a high near 83.

Saturday Night: Mostly clear, with a low around 61.

Sunday: Sunny, with a high near 82.