Mercury Soars as Late-Summer Heat Wave Bakes Pasadena

Pasadena temperatures are expected to soar today as sweltering conditions continue through the Labor Day weekend — with excessive heat warnings in effect across the region. The National Weather Service predicts a high of 108 Thursday.

The NWS issued an excessive heat warning for Pasadena that took effect at 11 a.m. Wednesday and will continue through 8 p.m. Monday.

The protracted heat wave began pushing up temperatures Tuesday, marking the onset of an expected weeklong period of oppressive conditions. The forecast has prompted calls for residents to take precautions against heat stroke and to conserve power whenever possible, with state officials warning of strain on California’s electrical grid.

“High pressure will persist over the area creating a prolonged period of very hot conditions with minimal coastal clouds,” according to the National Weather Service. “Triple-digit heat is expected for many valley and mountain locations through early next week including coastal areas during the Sunday and Labor Day peak. This heat may be record-breaking and will produce a very high risk of heat illness.”

The heat will continue as the weekend approaches, with a minor dip in temperatures anticipated Friday before heating up again for Saturday and Sunday, when “widespread triple-digit heat is expected,” including “kiln- like” heat of 115 degrees or more in the hottest areas, forecasters said.

Forecasters said the heat will persist through Monday, when the high- pressure system finally begins weakening. But some valley areas will likely still have extreme heat into next week.

“Drink plenty of fluids, stay in an air-conditioned room, stay out of the sun, and check up on relatives and neighbors,” the NWS urged. “Young children and pets should never be left unattended in vehicles under any circumstances.”

Forecasters also urged residents to be aware of the signs of heat stroke and to take precautions.

“Take extra precautions if you work or spend time outside,” according to the NWS. “When possible reschedule strenuous activities to early morning or evening. Know the signs and symptoms of heat exhaustion and heat stroke. Wear lightweight and loose-fitting clothing when possible. To reduce risk during outdoor work, the Occupational Safety and Health Administration recommends scheduling frequent rest breaks in shaded or air conditioned environments. Anyone overcome by heat should be moved to a cool and shaded location.”

Meanwhile, the California Independent System Operator, which manages the state’s power grid, issued a Flex Alert that urged voluntary conservation between 4 and 9 p.m. Wednesday, and it will be in effect again during the same hours Thursday. Additional Flex Alerts are anticipated throughout the weekend, particularly on Sunday and Monday, which are predicted to have peak electricity demand.

Due to the sustained high heat, the City of Pasadena activated a cooling center at Robinson Park Recreation Center, 1081 N. Fair Oaks Ave. It will be open Thursday and Friday from 8 a.m. to 8 p.m. and Saturday from 8 a.m. to 6 p.m.

The City official urged people to bring snacks. Water will be available.

The City will evaluate if the need exists to open additional days, according to a statement.

In addition, officials said public libraries are a great place to “escape the heat.” Here is a list of all branches: https://www.cityofpasadena.net/library/branches/

Here is the forecast from the National Weather Service:

Thursday: Sunny and hot, with a high near 108. Light south southwest wind increasing to 5 to 10 mph in the morning.

Thursday Night: Clear, with a low around 75. South southwest wind 5 to 10 mph becoming east after midnight.

Friday: Sunny and hot, with a high near 98. Light and variable wind becoming south southwest 5 to 10 mph in the afternoon.

Friday Night: Mostly clear, with a low around 74. South southwest wind around 5 mph becoming calm in the evening.

Saturday: Sunny and hot, with a high near 105.

Saturday Night: Mostly clear, with a low around 77.

Sunday: Sunny and hot, with a high near 107.

Sunday Night: Mostly clear, with a low around 77.

Labor Day: Sunny and hot, with a high near 104.

Monday Night: Mostly clear, with a low around 75.

Tuesday: Sunny and hot, with a high near 98.

Tuesday Night: Mostly clear, with a low around 71.

Wednesday: Sunny, with a high near 95.