MERCED — Anyone who has lived in the Northern San Joaquin Valley for any period of time knows that temperatures regularly hit triple digits in the summertime. As the common refrain goes, "At least it's a dry heat."
Except this time, it isn't.
The National Weather Service is predicting a sustained heat wave through at least the middle of next week. In Merced, temperatures are expected to reach the century mark today and top out at 108 degrees Tuesday before falling to 104 on Wednesday and what by then will seem a refreshing 100 Thursday for the Independence Day holiday.
"What's different about this one is, not only is it prolonged for several days, but it's combined with some moisture so it's going to feel a little muggier, a little bit uncomfortable," said Stefanie Henry, a meteorologist with the National Weather Service. "We're worried about heat stress on people and livestock and pets."
The Weather Service has issued an "excessive heat watch" from Saturday afternoon through Monday evening, predicting highs above 105 in the greater valley area, which includes Merced, Los Banos, Fresno and Bakersfield. The watch comes into effect when there is a combination of high temperatures for a prolonged period during in which it doesn't cool off much at night.
Merced residents should expect lows to drop only into the 70s by Saturday night. That's some respite, but not much.
"We are a little bit worried about it still being in the 70s," Henry said.
The city of Merced will open its cooling center at the Merced Civic Center on 18th Street from 4 to 8 p.m. Saturday through Wednesday. City spokesman Mike Conway said about a dozen people show up when the center is open in hot weather.
Cities and other organizations operate community swimming pools and water play areas in parks where folks can escape the heat of the day. Local reservoirs offer a respite from the sun, though officials caution people not to drink alcohol and swim. Another option, for those who can manage it, is to get away completely: Monterey is expecting a high of about 70 throughout next week, with San Francisco a degree or two warmer.
Looking ahead, there's no sign of any real relief.
"It's hard to tell right now," Henry said. Though temperatures are expected to drop a bit late next week, any drastic changes are unlikely as the system will weaken rather than move away. "I don't really see much of an end."
Modesto Bee Breaking News Editor Patty Guerra can be reached at firstname.lastname@example.org or (209) 578-2343. Follow her on Twitter @pattyguerra.
SAFETY TIPS• Drink plenty of water.
• Avoid strenuous activity during hottest part of the day.
• Never leave children or pets unattended in a vehicle.
• Wear lightweight and light-colored clothing.
• Bring pets inside, where the air conditioning is on.
• Check on family, friends and neighbors who spend much of their time alone or are more likely to be affected by the heat.
• If you must be out in the heat, try to rest in shady areas.
• Listen to local weather forecasts and stay aware of upcoming temperature changes.
• Don't drink liquids that contain alcohol or large amounts of sugar, which cause you to lose more body fluid.
• Wear protective clothing and a wide-brimmed hat with sunglasses.
• Fans alone won't protect you from extreme heat; use your air conditioner and keep it well maintained.
• If your indoor temperature remains at more than 90 degrees, seek shelter in an air-conditioned building.
Sources: National Weather Service, Modesto Regional Fire Authority