Rains to Continue All Day, Possibly Intensifying Sunday Afternoon

A storm system continues to move across the Pasadena / Altadena area today, bringing rain and potential thunderstorms through Monday, with officials warning of possible flooding in burn scar areas. 

The National Weather Service forecasts rainfall rates increasing to between a quarter and third of an inch per hour by Sunday afternoon, with isolated areas potentially seeing up to 0.75 inches per hour after 4 p.m.

In total, Los Angeles County is expected to receive 0.75 to 1.25 inches of rain in valley areas and up to 2 inches in mountainous regions. 

Meteorologists warn of possibly intense but brief downpours, gusty winds, and possibly even small hail from thunderstorms. 

Temperatures will remain cool, with highs in the 50s through Monday and overnight lows dropping into the low 40s. Tuesday will bring gradual clearing with highs near 60 degrees. 

Forecasters predict dry conditions by midweek, with temperatures warming to the low 60s before another weaker storm system approaches the area by week’s end. 

Here is the latest Pasadena-area forecast from the National Weather Service as of 3:34 a.m. Sunday morning:

Today: Showers likely, then showers and possibly a thunderstorm after 10 a.m. High near 53. Southeast wind 5 to 10 mph, with gusts as high as 15 mph. Chance of precipitation is 90%. New rainfall amounts between a quarter and half of an inch possible. 

Tonight: Showers and possibly a thunderstorm. Low around 42. East wind 5 to 10 mph. Chance of precipitation is 90%. New rainfall amounts between a quarter and half of an inch possible. 

Monday: Showers likely and possibly a thunderstorm. Mostly cloudy, with a high near 55. East wind around 5 mph becoming south in the afternoon. Chance of precipitation is 60%. New precipitation amounts of less than a tenth of an inch, except higher amounts possible in thunderstorms. 

Monday Night: A 30 percent chance of showers, mainly before 10pm. Mostly cloudy, with a low around 41. West southwest wind around 5 mph becoming calm in the evening. New precipitation amounts of less than a tenth of an inch possible. 

Tuesday: A 20 percent chance of showers after 10am. Mostly sunny, with a high near 57. North northeast wind around 5 mph becoming south in the morning. 

Tuesday Night: Mostly clear, with a low around 39. 

Wednesday: Sunny, with a high near 61. 

Wednesday Night: Mostly clear, with a low around 40. 

Thursday: Sunny, with a high near 62. 

Thursday Night: Mostly cloudy, with a low around 42. 

Friday: Partly sunny, with a high near 62. 

Friday Night: Mostly cloudy, with a low around 43. 

Saturday: Partly sunny, with a high near 58.