Pasadena Temperatures Could Plummet 15 Degrees as Marine Layer Returns

Temperatures in Pasadena could drop 15 degrees over the next two days as a significant cooling trend grips the region, with highs falling from 89 degrees Thursday to 77 degrees by Saturday, National Weather Service forecasters said.

The dramatic temperature swing marks the most significant weather change in the current forecast period, according to the Los Angeles office of the National Weather Service. Low pressure developing along the West Coast is pushing high pressure eastward and allowing marine influences to penetrate inland areas.

Thursday represents the final day of recent warm conditions, with temperatures reaching a high near 89 degrees. Patchy fog is expected through late morning before skies gradually clear.

Friday will bring a sharp cooldown with highs reaching only 80 degrees. Morning fog will persist before 11 a.m., with cloudy skies giving way to gradual clearing by afternoon.

Marine layer activity will increase significantly during the cooling trend. Patchy fog is forecast to develop after 11 p.m. each night through the weekend, persisting until late morning hours.

Saturday offers the coolest conditions with highs near 77 degrees under mostly sunny skies after morning fog dissipates. Sunday begins a slight warming trend with temperatures climbing to 79 degrees.

Morning commuters should expect reduced visibility during fog periods, particularly along the 210 Freeway corridor and surface streets in lower-lying areas.

Next week will see below-normal temperatures persist Monday through Wednesday. Highs will hover in the low 80s, about 5 to 10 degrees below typical June averages for Pasadena.

A warming trend is expected to begin Wednesday as high pressure starts rebuilding from the eastern Pacific.

Wind conditions will remain manageable at 5 to 10 mph from various southerly directions throughout the forecast period.

Here is the latest forecast for Pasadena from the National Weather Service as of 3:33 a.m. Thursday:

Juneteenth: Patchy fog before 11:00 a.m. Otherwise, cloudy through mid morning, then gradual clearing, with a high near 89. South southwest wind 5 to 10 mph.

Tonight: Patchy fog after 11:00 p.m. Otherwise, increasing clouds, with a low around 60. South southwest wind 5 to 10 mph becoming light south southeast in the evening.

Friday: Patchy fog before 11:00 a.m. Otherwise, cloudy through mid morning, then gradual clearing, with a high near 80. Light south wind becoming south southwest 5 to 10 mph in the afternoon.

Friday Night: Patchy fog after 11:00 p.m. Otherwise, increasing clouds, with a low around 58. South southeast wind 5 to 10 mph.

Saturday: Patchy fog before 11:00 a.m. Otherwise, mostly sunny, with a high near 77. South southwest wind 5 to 10 mph.

Saturday Night: Patchy fog after 11:00 p.m. Otherwise, mostly cloudy, with a low around 56.

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

Sunday Night: Mostly cloudy, with a low around 57.

Monday: Mostly sunny, with a high near 81.

Monday Night: Mostly cloudy, with a low around 57.

Tuesday: Mostly sunny, with a high near 81.

Tuesday Night: Mostly cloudy, with a low around 59.

Wednesday: Mostly sunny, with a high near 84.