Comment on this story
comment
More than 80 million Americans remain under heat warnings as very high temperatures grip the Lower 48 through the weekend.
Readings near or above 100 degrees stretch from the Mexican border to the Canadian border on Friday. Over the next week, 85 percent of Lower 48 residents could experience temperatures of 90 or higher, with nearly 20 percent reaching or exceeding 100.
Heat advisories centered on Missouri cover parts of 13 states from the central and southern Plains to the mid-South. Additional warnings are in place for much of the Northeast Urban Corridor. Extreme heat advisories are also in effect Friday for 10 million people in the desert Southwest.
Both Boston and New York City have changed triathlon plans for the weekend. In Boston, it has been postponed until August, and New York’s has been shortened by about half.
Further south, Washington, DC, remains under a heat emergency declared by the mayor until Monday. City pools will be open late, while shelters and cooling centers are also available.
In Texas and much of the Southern Plains, farmers and ranchers are struggling with burned fields and stressed livestock. The persistence of hot and dry conditions is unheard of in parts of the region.
Dozens of record highs have already been broken in recent days, and about three dozen may be under threat over the weekend. Numerous record warm lows are also likely.
An excessive heat warning is in place for much of the desert Southwest on Friday, including Phoenix, Las Vegas and Palm Springs, California.
“Well above normal high temperatures will likely exceed 110 to 115 degrees today for Phoenix and all lower desert communities in the region,” the Weather Service wrote.
This comes after a series of record highs on Thursday. They include Barstow, California, at 112; Bishop, Calif., at 106; and Desert Rock, Nevada, at 108. A record low of 90 was also tied in Las Vegas. In Needles, California, the overnight low was a remarkable 95 Wednesday.
Friday is likely the last of this current bout of excessive heat for the region as temperatures return to normal levels near 100. The moisture associated with the summer monsoon, a change in winds that bring rain in the region is expected to increase, helping them. build clouds and lower temperatures.
In the Southern Plains and Mid-South, temperatures of 100 or more have been the norm for weeks. Long-term drought and the spread of rapid drought only increase the feedback loop between dry and warm conditions.
A slew of record highs fell across Texas on Thursday, including in San Antonio, where it hit 102. It was the fifth-highest record there this month, above eight record highs in June and eight in May. The city has now seen 42 days of 100 or more in 2022, compared to an average of 19 over an entire summer.
San Antonio had 17 days of triple-digit heat in June. The norm is two.
Additional record highs Thursday included Houston (at Hobby Airport) at 100, Austin at 103 and College Station at 105. Numerous places in Texas, including Abilene and Dallas, also set record lows for the date.
Record highs and record lows also occurred Thursday in Louisiana, Arkansas, Oklahoma and Missouri.
Mercury rises in the Mid-Atlantic and Northeast
Although the Northeast has avoided extreme heat this summer, the region is experiencing the hottest weather of the season so far over the weekend.
Boston, Providence and Hartford, as well as coastal areas such as Cape Cod, are under heat warnings Saturday and Sunday. Temperatures inland are expected to reach record highs in the mid-90s to near 100, while colder spots near the coast also soar in the near or upper 90s.
It’s a similar story in New York City and Philadelphia, where a heat advisory runs Friday through Sunday, and each day should see readings reach at least the mid-to-upper 90s.
“There will be a chance that some spots could reach excessive heat advisories on Sunday, and that will need to be monitored in later forecasts,” NWS New York City wrote.
New Jersey City and parts of New York City are most at risk of reaching heat advisory criteria, which include heat index values near 110. Newark, in the middle of a heat island major urban, has reached 100 twice this week.
D.C. heat wave: Could hit 100 for first time in six years Sunday
From the DC and Baltimore metro areas to Richmond, temperatures will climb into the mid-90s on Friday, with upper 90s nearing 100 this weekend. Additional heat alerts seem like a good bet for these areas.
Numerous record highs are in play before a cold front temporarily interrupts the brutal temperatures early next week. Sunday is likely the hottest day of the stretch, and many records may fall.
In addition to the hot daytime temperatures, relief at night will be minimal. Temperatures in urban areas may not fall far below the 80s, as others drop further into the 70s.
We’re getting the Northwest heat back next week
So far this summer has been relatively tame across much of the Pacific Northwest. But high pressure building up in the area from the Gulf of Alaska early next week sets the stage for the hottest weather of the year so far.
“Western Washington will experience an extended period of well above normal temperatures and long-term dry conditions,” NWS Seattle wrote.
2021 Pacific Northwest heat wave ‘virtually impossible’ without climate change, scientists say
The hot weather hits Monday and lasts through much of the work week. With temperatures in the 90s during the days, heat alerts may be issued for parts of the area as the forecast approaches.
A large “heat dome” of high pressure has been anchored over the southern United States for weeks. At times, it has expanded to reach the West Coast and the East Coast.
Sinking high-pressure air tends to hinder cloud development and storms, maximizing the amount of summer sunshine. A little more than half of the Lower 48 is in drought conditions, according to the US Drought Monitor update released Thursday. Almost 70 percent are classified as at least abnormally dry.
Drought and high pressure usually go hand in hand. The extended stay of the heat dome has helped maintain the drought and high temperatures.
Britain’s freak heat broke records. Here’s what happened.
Human-driven climate change is also increasing the heat. Temperatures tend to be several degrees warmer than they might be without it — and this has been underscored in the climate this summer in the United States and around the world.