The main purpose of this ongoing blog will be to track planetary extreme, or record temperatures related to climate change. Any reports I see of ETs will be listed below the main topic of the day. I’ll refer to extreme or record temperatures as ETs (not extraterrestrials).😉
Main Topic: Advent of Western Heatwave Chevron and Heatwave British Petroleum Update
Dear Diary. The bad news is that the U.S. has two separate major heatwaves to contend with on this Thursday. The good news is that enough dry air has filtered into Texas and Oklahoma such that high heat indexes have come down, so the National Weather Service has dropped most heat advisories across most of those states even though temperatures remain very high. Therefore, using my criteria, Heatwave British Petroleum has been dropped from being categorized as a “historic” CAT4 to a major CAT3 looking at current conditions across the South:
This is not to write that Heatwave BP was once a CAT4 across Mexico and Texas. If it becomes determined that hundreds of deaths occurred from the system, then historically it will retain that status. Pacific Northwest Heatwave Beta from 2021 attained a historic CAT5 status since more than 1000 deaths were blamed for it, for example.
Today let’s concentrate on the newest threat to health, Heatwave Chevron, named going down this list of fossil fuel names, since I’m playing a blame game:
Over the next few days, the heat dome in association with western Heatwave Chevron will wax while that of the eastern heatwave will wane:
Here is a good summary on what to expect this Fourth of July Holiday Weekend from my friend Matthew Cappucci writing for the Washington Post:
California’s first major heat wave of the year may break record temperatures – The Washington Post
California set to face its first major heat wave of the year
Temperatures could reach 110 degrees in the Central Valley
Updated June 28, 2023 at 12:45 p.m. EDT|Published June 28, 2023 at 11:52 a.m. EDT
High temperatures on Saturday as predicted by the National Weather Service. (Pivotal Weather)
Triple-digit temperatures aren’t uncommon in California in the summertime, but the first major heat wave of the season is about to push readings toward record territory. Excessive heat watches and heat advisories blanket much of the state from the Central Valley to Orange County, with a few areas set to approach 110 degrees.
The worst of the heat will come between Friday and Sunday, with high temperatures peaking 10 to 15 degrees above average. While humidity won’t be an issue, the hot temperatures alone will be hazardous, especially for the unhoused and other vulnerable populations.
Extreme Texas heat wave to swell across southern, central U.S.
How bad is heat risk near you?
(The Washington Post) We’re tracking dangerous heat waves across the United States daily. Look up your city to see extreme heat risks near you.
“Extreme heat will significantly increase the potential for heat related illnesses, particularly for those working or participating in outdoor activities,” wrote the National Weather Service.
While the hot, dry weather could also make it easier for fires to grow, recent cool weather has allowed some of the moisture from a historically wet winter to linger in the soil and vegetation. That will work to counteract wildfire risk somewhat for now, until deeper in the season when summer’s heat has had more time to desiccate the landscape.
The National Weather Service also cautioned residents against cooling off in area rivers, streams and lakes. Many are still exceptionally cold due to earlier ice melt from the Sierra Nevada, posing a hypothermia risk. The swift currents, the result of a record snowpack, can also easily sweep swimmers away.
Excessive heat warnings stretch from Redding and Shasta Dam south toward Edwards Air Force Base, and include Sacramento, Bakersfield, Tulare and Modesto. A heat advisory is in place just inland from the immediate coastline, and covers King City, San Jose, Napa and Santa Rosa.
While Wednesday will feature seasonable highs, temperatures are expected to lurch on Thursday before peaking Friday, Saturday and Sunday. Sacramento will only be in the mid 90s on Wednesday, which is close to average, but could see highs around 103 on Thursday and between 105 and 107 into Sunday.
The heat dome as simulated by the American GFS model. (WeatherBell)
While that’s about a dozen degrees hotter than average, it won’t come close to breaking the records of 112, 109 and 108 set in 1934, 1950 and 1950 respectively.
In Bakersfield, the existing records are 112 on Thursday, 111 on Friday and 115 Saturday. Highs of 108 degrees are more likely. The average late June high is 96 degrees.
“Probabilities are around 40 to 65 percent for high temperatures of 108 degrees or more at Valley locations,” wrote the National Weather Service in Hanford. “These upcoming temperatures will create widespread moderate to high risk for heat related illness for persons in the San Joaquin Valley, lower foothills and in the desert areas, especially on Saturday and Sunday.”
Redding, in Northern California, could spike to 107 degrees Friday and 110 on Saturday. That could threaten the record of 111 set in both 2015 and 1972.
Instigating the heat will be a ridge of high pressure, known colloquially as a heat dome, that will slide ashore from the eastern Pacific and saunter over central California. Heat domes bring hot, sinking air, which dries out and warms up even more.
Meteorologists gauge the intensity of a heat dome based on how much the atmosphere expands, since warm temperatures make columns of air bulge upward and grow vertically. This heat dome will raise the height of the atmosphere’s halfway point, or the midpoint of the atmosphere’s mass, vertically by about the length of a football field.
The heat wave should relent somewhat into Monday as the heat dome shifts to the east. That would put California on the backside of clockwise-spinning high pressure, with winds out of the southwest bringing a more moderate, cooling flow off the Pacific.
More on extreme heat
Our warming climate: It’s not just you — summers in the U.S. are getting hotter, and experts say heat waves will likely become even more frequent and intense. Look up your city to see your extreme heat risk with our tracker. Take a look at what extreme heat does to the human body.
How to stay safe: It’s better to prepare for extreme heat before you’re in it. Here’s our guide to bracing for a heat wave, tips for staying cool even if you don’t have air conditioning, and what to know about animal safety during extreme heat. Traveling during a heat wave isn’t ideal, but here’s what to do if you are.
Understanding the science: Sprawling zones of high pressure called heat domes fuel heat waves. Here’s how they work. You can also read more about the link between weather disasters and climate change, and how leaders in the U.S. and Europe are responding to heat.
By Matthew Cappucci Matthew Cappucci is a meteorologist for Capital Weather Gang. He earned a B.A. in atmospheric sciences from Harvard University in 2019 and has contributed to The Washington Post since he was 18. He is an avid storm chaser and adventurer, and covers all types of weather, climate science, and astronomy. Twitter
Here are some “ET’s” recorded from around the planet the last couple of days, their consequences, and some extreme temperature outlooks, as well as any extreme precipitation reports:
Here is more climate and weather news from Thursday:
(As usual, this will be a fluid post in which more information gets added during the day as it crosses my radar, crediting all who have put it on-line. Items will be archived on this site for posterity. In most instances click on the pictures of each tweet to see each article. The most noteworthy items will be listed first.)
Wow! This blog post is really eye-opening. I didn’t know that there was such a thing as a Western Heatwave. I’m glad that I’m reading it so that I can be prepared for it.