Spring-Like Heat Wave to Push Pasadena Temperatures to 85° by Monday

A warming trend will bring unseasonably high temperatures to Pasadena and Altadena through the weekend, with highs potentially reaching the mid-to-upper 80s by Monday, National Weather Service forecasters said  today.

Temperatures are expected to climb 8 to 12 degrees above normal as a high-pressure ridge builds over Southern California.

Wednesday’s conditions in Pasadena feature clear skies with temperatures reaching the mid-70s, a noticeable jump of 4 to 8 degrees from Tuesday. Light northeasterly winds moved through the area in the morning, remaining below advisory levels.

A brief cooling trend will interrupt the warming pattern Thursday as a weak trough pushes through the region. The offshore flow will continue from the north, but the easterly component will weaken considerably, even turning onshore by afternoon. This sea breeze will help keep temperatures slightly lower than Wednesday.

But by Friday, temperatures will begin climbing again under dry northwest flow aloft. Most areas around Pasadena will warm a couple of degrees compared to Thursday.

The weekend marks the beginning of a temperature surge.

Saturday’s temperatures will remain similar to Friday’s, mostly in the mid-70s. However, Sunday will see a jump of 2 to 4 degrees, potentially reaching the upper 70s to low 80s.

No rain is expected throughout the forecast period, with mostly clear skies dominating the region.

Monday is expected to be the warmest day, with an additional 4 to 6 degrees of warming forecast. This will push temperatures 8 to 12 degrees above normal for this time of year, with valley locations possibly reaching the low 90s.

No heat advisories have been issued yet.

The ridge of high pressure will likely begin to weaken after peaking on Monday, though forecasters say specific details remain uncertain beyond Tuesday.

Here is the latest forecast for Pasadena from the National Weather Service as of 3:17 a.m. on Wednesday, March 19:

Today: Sunny, with a high near 76. Northeast wind 5 to 10 mph becoming southwest in the afternoon.

Tonight: Mostly clear, with a low around 48. Southwest wind 5 to 10 mph becoming light and variable after midnight. Winds could gust as high as 15 mph.

Thursday: Sunny, with a high near 75. Light and variable wind becoming south southwest 5 to 10 mph in the afternoon.

Thursday Night: Mostly clear, with a low around 47. Southwest wind 5 to 10 mph becoming north northeast after midnight. Winds could gust as high as 15 mph.

Friday: Sunny, with a high near 77. Calm wind becoming southwest around 5 mph in the afternoon.

Friday Night: Mostly clear, with a low around 49.

Saturday: Patchy fog before 11:00 a.m. Otherwise, partly sunny, with a high near 75.

Saturday Night: Mostly clear, with a low around 51.

Sunday: Sunny, with a high near 79.

Sunday Night: Mostly clear, with a low around 55.

Monday: Sunny, with a high near 85.

Monday Night: Mostly clear, with a low around 58.

Tuesday: Sunny, with a high near 84.