Temperatures in Pasadena will climb into the mid-90s starting Tuesday, Sept. 8, and peak near 98 degrees Wednesday as a heat wave follows last weekend's rain from Tropical Storm Marie.
The National Weather Service issued a heat advisory for Los Angeles County on Monday, Sept. 7, at 11:55 a.m. The advisory covers the San Gabriel Valley and runs from 10 a.m. Tuesday through 8 p.m. Thursday, Sept. 10, according to the Pasadena Star-News. The agency warned that temperatures 10 to 15 degrees above normal, combined with lingering tropical humidity, could extend the advisory into Friday.
The NWS Pasadena forecast calls for a Tuesday high near 95°F with heat index values as high as 106, a Wednesday high near 98°F and a Thursday high near 95°F, Pasadena Now reported. Overnight lows will hover around 70°F, offering little relief.
NWS meteorologist Rose Schoenfeld told LAist that lingering tropical humidity from Marie will compound the heat. "We're looking at a pretty significant heat event, especially for those near the coast without air conditioning," Schoenfeld said.
Offshore flow midweek may delay sea breezes, allowing heat to build closer to the coast, according to the NWS forecast. Gradual cooling is expected by Friday, with highs dropping into the upper 80s by the weekend.
Weekend rain triggered burn-scar flood advisories
Tropical Storm Marie dropped roughly a quarter to three-quarters of an inch of rain across Los Angeles County over the Labor Day weekend, according to NWS data reported by Patch. The storm triggered flood advisories for several burn-scar areas, including the Summit and Bridge fire scars in eastern Los Angeles County, according to the Orange County Register, and the Franklin and Palisades fire scars in west central Los Angeles County, according to Patch.
The Eaton Fire burn scar remains one of Pasadena's greatest flooding concerns. Nallely Procopio, Pasadena's Emergency Services manager, said in a Sept. 1 CBS LA report that flooding risks on the charred hillsides will stay elevated for three to five years. Los Angeles County officials have echoed that warning, stating burn-scar areas face higher risk of debris flows, landslides and flooding for up to five years after a significant wildfire.
No Pasadena-specific flood advisory for the Eaton Fire scar was confirmed during the weekend rain.
Staying cool
During the city's August heat wave, Pasadena designated Robinson Park Recreation Center at 1081 N. Fair Oaks Ave. as its official cooling center. The city had not announced updated cooling center hours for this week's heat as of Tuesday morning. Residents can check the city's Extreme Weather Portal at CityOfPasadena.net/extreme-weather-portal for current hours and locations.
Pasadena Public Libraries also offer air-conditioned spaces. Los Angeles County maintains a list of cooling centers at ready.lacounty.gov/heat/.
Pasadena Water and Power advises customers to reduce energy use during peak hours, 4 to 9 p.m., and set thermostats to 78°F or higher. Residents can sign up for emergency alerts through the Pasadena Local Emergency Alert System (PLEAS) at CityOfPasadena.net/Fire/PLEAS/.
