Rain and Colder Weather on Saturday

An unusual late April storm system is expected to bring rainfall and unseasonably cool temperatures to the Pasadena area on Saturday, according to National Weather Service forecasters.

The storm will deliver between one-quarter and one-half inch of rain, with temperatures dropping 10 to 20 degrees below normal levels for this time of year.

Friday will start cool with patchy morning drizzle before clouds gradually give way to partial afternoon clearing. High temperatures will reach only 66 degrees with south-southeast winds at 5 to 10 mph.

Weather conditions will deteriorate Friday night as clouds increase ahead of the approaching storm. An upper low pressure system currently off Northern California’s coast will track eastward, reaching Pasadena by late Saturday morning.

Rain will begin around 11:00 a.m. Saturday and continue through the afternoon and early evening, with precipitation chances at 80%.

Saturday’s high temperature will struggle to reach 58 degrees, potentially setting new record low maximums for the date.

“These temperatures could be 15 to 20 degrees below normal for late April in Pasadena,” the National Weather Service stated.

Brisk east-southeast winds at 5 to 10 mph, shifting to south-southwest in the afternoon, will make it feel even cooler. Occasional gusts up to 15 mph are possible Saturday afternoon.

The rainfall is expected to taper off by late evening, with just a 20% chance of lingering showers before 11:00 p.m.

While no formal weather advisories have been issued specifically for Pasadena, residents in nearby mountain communities should be aware that Winter Weather Advisories may be issued as snow levels drop to between 4,500 and 5,500 feet in nearby mountains..

Sunday will bring improving conditions with mostly sunny skies and a high temperature of 67 degrees.

The extended forecast shows a warming trend beginning Sunday and continuing through next week. Monday will see sunny skies with temperatures climbing to around 72 degrees, with highs reaching the upper 70s by Tuesday.

Here is the latest forecast for Pasadena from the National Weather Service as of 4:38 a.m. on Friday, April 25:

Friday: Patchy drizzle and fog before 11:00 a.m. Partly sunny, with a high near 66. South southeast wind 5 to 10 mph.

Friday Night: Mostly cloudy, with a low around 53. Southwest wind 5 to 10 mph.

Saturday: Rain, mainly after 11:00 a.m. High near 58. East southeast wind 5 to 10 mph becoming south southwest in the afternoon. Winds could gust as high as 15 mph. Chance of precipitation is 80%. New precipitation amounts between a quarter and half of an inch possible.

Saturday Night: A 20 percent chance of rain before 11:00 p.m. Mostly cloudy, with a low around 45. South southwest wind 5 to 10 mph becoming light after midnight.

Sunday: Mostly sunny, with a high near 67.

Sunday Night: Partly cloudy, with a low around 48.

Monday: Sunny, with a high near 72.

Monday Night: Clear, with a low around 51.

Tuesday: Sunny, with a high near 77.

Tuesday Night: Mostly clear, with a low around 54.

Wednesday: Sunny, with a high near 76.

Wednesday Night: Partly cloudy, with a low around 55.

Thursday: Mostly sunny, with a high near 76.