LOS ANGELES - Fall may officially be here, but Southern California is heading straight back into summer like temps as a prolonged heat wave threatens to push temperatures into the triple digits across Los Angeles and Orange County.
What we know:
According to the National Weather Service (NWS) the heat wave will kick off this Friday and last until at least next Thursday or possibly even longer.
LA County weather
An Extreme Heat Warning is in effect from 10 a.m. Friday through 8 p.m. Thursday for coastal and valley areas of Los Angeles County.
Temperatures could reach 90 degrees along the coast and 105 degrees in the valleys during the warning period, according to the NWS.
Friday is expected to bring temperatures 10 to 15 degrees above normal, with highs in the mid to upper 80s across most coastal areas and the lower to mid-90s along parts of the Los Angeles County coast. Valley temperatures are expected to range from the upper 90s to 105 degrees.
Saturday is expected to be the hottest day of the next seven, with temperatures rising another 2 to 4 degrees in coastal and valley areas and locally as much as 6 degrees, forecasters said.
Most coastal areas are expected to reach the 90s Saturday, while valley temperatures could range from 100 to 107 degrees, or about 15 to 20 degrees above normal.
The heat is expected to ease only slightly Sunday, with temperatures remaining generally 10 to 15 degrees above normal Monday through Wednesday.
Orange County weather
Extreme Heat Warnings will also be in effect from 10 a.m. Friday through 8 p.m. Thursday for coastal and inland Orange County.
High temperatures in coastal Orange County are expected to range from the mid-80s to around 90 near the coast and reach the lower to mid-90s near higher coastal terrain, according to the NWS. Inland Orange County highs are expected to range from the mid-90s to near 100.
Overnight lows in both coastal and inland Orange County are expected to remain mostly in the lower to mid-70s.
What's next:
Humidity is expected to increase Monday through Wednesday as moisture from Hurricane Rachel moves into the region, with a 5% to 15% chance of afternoon showers or thunderstorms in the mountains, according to the weather service.
Forecasters said the latest long-range models indicate conditions could begin improving around Oct. 10.
What they're saying:
"Even though this heat wave will not likely produce record heat it will still be very dangerous due to the prolonged duration of the event," according to the NWS. "The relentless heat will have a hazardous wearing down effect on people, (especially) the very young and old."
What you can do:
The NWS advised residents to drink plenty of fluids, stay in air-conditioned areas, avoid the sun and check on relatives and neighbors during the heat wave. Residents were also urged not to leave children or pets in unattended vehicles.
Timeline:
Extreme Heat Warning Begins: Friday, Oct. 2 (10:00 AM)
- Temperatures climb 10 to 15 degrees above average.
- Coastal areas reach mid-80s to lower 90s, while inland valleys hit the upper 90s to 105°F.
Peak Heat Across SoCal: Saturday, Oct. 3
- The hottest day of the seven-day period.
- Valleys reach 100°F to 107°F (15–20° above normal), while most coastal zones warm into the 90s.
Slight Cooling & Rising Humidity: Sunday, Oct. 4 – Wednesday, Oct. 7
- Temperatures remain 10 to 15 degrees above average.
- Moisture from Hurricane Rachel brings higher humidity and a 5% to 15% chance of afternoon mountain thunderstorms.
Heat Warning Expires: Thursday, Oct. 8 (8:00 PM)
- The formal Extreme Heat Warning concludes, though long-range models indicate temperatures may not fully normalize until around Oct. 10.
The Source: Information for this story came from the National Weather Service and City News Service.