After a mild spring, temperatures are expected to heat up steadily later this week across the Bay Area, culminating in a heat wave in the mid-to-high 90s in many Bay Area cities and up to 105 in Livermore and other inland areas by this weekend.
“Summer is definitely arriving. It may have been a little late coming to the the Bay Area, but it’s here now,” said Dial Hoang, a meteorologist with the National Weather Service in Monterey.
The warming comes as a series of extreme weather events are unfolding across the United States and the world.
Forecasters say Phoenix is likely to break its all-time record of 18 days in a row over 110 degrees, with 10 straight already in the books by Sunday, and 115+ forecast for the coming days. Las Vegas is expected to reach 117 by the weekend. And California’s Central Valley also will roast in the coming week, the National Weather Service predicts, with Bakersfield and Redding forecast to hit 114 this weekend, Sacramento 109, and Death Valley as high as 128, which would be among the highest temperatures ever recorded on Earth.
The sizzling temperatures are being driven by a high pressure system, called a “heat dome,” over the Southwest.
Excessive Heat Watch for the interior Bay Area and Central Coast, from Friday into Sunday. High temperatures will range from the 90s to the mid 100s. Never leave children and pets in vehicles, and stay hydrated! #CAwx pic.twitter.com/kGeMpzFczV
— NWS Bay Area 🌉 (@NWSBayArea) July 10, 2023
The searing conditions will spread, forecasters say, bringing dangerously hot conditions across the much of the American West for the next 7 days or more.
Meanwhile, hundreds of wildfires continue to burn in Canada. So far this year, 22.7 million acres have burned there, according to the Canadian Interagency Forest Fire Centre, breaking the previous record of 17.5 million acres in 1995 with at least three months left in the fire season.
Smoke from those fires, led by the 1.5 million-acre Donnie Creek Fire in British Columbia, has created significant health hazards in recent weeks in American cities — with New York, Chicago, Detroit, Pittsburgh and others breaking records for particulate pollution.
Farther south, ocean surface temperatures off the Florida Keys reached an unprecedented 95 degrees on Sunday.
Lest anyone think this is some kind of mapping error, SST reports from buoys around the Florida Keys posted as of ~7 PM ET Sun are downright shocking, e.g.:
Key West 92.1F
Vaca Key 94.3F
Johnson Key 95.7F
😱https://t.co/MsvQCqqg8W https://t.co/VXHLhnqzAB— Bob Henson (@bhensonweather) July 9, 2023
And in Texas, high humidity and extreme heat are expected to spike the “heat index” — what the temperature feels like to the human body — to between 105 to 112 degrees this week in Dallas, Houston, Austin and San Antonio. Health experts say a heat index above 104 degrees can cause sun stroke, heat exhaustion and other problems. It also strains power grids as millions of people turn up air conditioning, increasing the risk of blackouts.
“I’m very concerned,” said biologist Chris Field, director of Stanford University’s Woods Institute for the Environment. “Extreme heat is deeply dangerous, especially for the elderly, the very young, and people with infirmities. Extreme heat is much more difficult to manage among people who work outdoors and the unhoused.”
Hot weather is normal for summer.
But El Niño conditions this year, combined with the ongoing impacts of climate change, are making droughts, heat waves and wildfire danger more severe, scientists say, increasing public health threats, and the threat to wildlife.
By some measurements, three days last week broke the all-time average daily global temperature since modern records began.
“Climate change is not necessarily bringing about completely brand new types of weather,” said Daniel Swain, a UCLA climate scientist, on Monday. “It is shifting the envelope of weather that we experience. It’s not that we’ve never experienced heat waves before, or extreme precipitation events, or floods or wildfires. But what it’s doing is changing the character of those events. It’s upping the ante.”
Global temperatures have risen 2.1 degrees Fahrenheit since 1880, mostly due to the burning of fossil fuels, which traps heat in the atmosphere. The 10 warmest years since 1850 on Earth, when consistent modern temperature records began, have all occurred since 2010, according to NOAA, the National Oceanic and Atmospheric Administration, which is the parent agency of the National Weather Service.
Last month was the warmest June ever recorded, with record low levels of Antarctic sea ice. Many climate researchers say 2023 could well break another record for warmest year ever recorded.
“We are in uncharted territory and we can expect more records to fall as El Niño develops further and these impacts will extend into 2024,” said Chris Hewitt, director of climate services at the World Meteorological Organization. “This is worrying news for the planet.”
The world just had the hottest June on record, with unprecedented sea surface temperatures and record-low Antarctic sea ice extent, according to a new report. #StateOfClimate
🔗 https://t.co/7ScabFvIG4 pic.twitter.com/SMOcXdnVUJ
— World Meteorological Organization (@WMO) July 6, 2023
So far this year, the Bay Area has largely escaped serious heat. On the hottest day of the year so far, July 1, Livermore hit 107 degrees, Santa Rosa 104, San Jose 94, Oakland 80, and San Francisco 77.
As temperatures rise in many Bay Area cities later this week into the 80s and 90s, with inland areas hitting the low 100s, the region will still be 10 to 20 degrees cooler than the Central Valley.
Coastal clouds, and breezes blowing from the ocean toward the land provide a form of natural air conditioning.
“The Pacific Ocean helps moderate our temperatures a lot,” Hoang said. “That will really help us out this week.”
Fort St John, BC 🇨🇦
Flames from the Donnie Creek wildfire burn along a ridge in British Columbia. More than 500 fires have been raging across Canadian provinces for nearly a month, spreading an orange-brown haze across eastern 🇨🇦 and the midwest and north-east regions of the 🇺🇸… pic.twitter.com/eaUjOyIvqK— Antoine D ☭ (@AD1968F) July 8, 2023
Fire risk remains relatively low also due to the soaking winter weather that broke California’s drought and increased moisture levels in shrubs and trees. Some parts of the Sierra Nevada are still covered in snow, including the high country of Yosemite National Park.
Later in the fall, by September or October, the risk of wildfires will increase after the snow is gone, multiple heat waves have dried out vegetation, and winds shift to a traditional fall pattern blowing warm air from Nevada toward the coast. While the Bay Area has largely been spared so far, much of the rest of the West and the United States is already struggling with a summer more severe than any that humans have experienced for thousands of years.
“Yes, it’s hot in July most of the time in many places,” Swain said. “But what we are seeing this July is on a different level.”
Source: www.mercurynews.com