'Excessive' weather events mark summer solstice in the U.S.

By Bill Chappell

Published June 21, 2023 at 2:15 PM EDT

Red and dark-red blotches cover a map of the United States, as the Climate Protection Center warns of the risk of excessive heat. While the biggest threat is in Texas, areas far north as Iowa and Illinois are also seen in a shade of red.

"Excessive" is the word of the day in the National Weather Service's forecast for the summer solstice — the term appears seven times, describing record heat and torrential rainfall that different areas of the U.S. are experiencing.

Forecasters said extreme weather would hit many parts of the country on the longest day of the year, as the 2023 summer solstice occurred at 10:58 a.m. ET, according to the U.S. Naval Observatory.

"The never-ending excessive heat across Texas and parts of the Southern U.S. will persist the rest of week with dangerous conditions," the NWS said.

People are trying to cope with extreme weather against the backdrop of two longer-term patterns that could combine to make this summer a tough one to endure. Climate change is making once-unthinkable heat waves more likely; and an El Niño pattern of warmer sea temperatures is now in effect, threatening to amplify summer weather extremes even further.

Heat is punctuated by dangerous storms

The heat wave has been searing a large chunk of the U.S., from West Texas to Florida. High humidity has been driving the "feels like" heat index even higher, increasing the health risks. A number of tornadoes have also struck, with several deaths reported in the past week.

"The most recent record fell on Monday when the temperature hit 105 in San Antonio, beating the previous record high of 103 set in 1918 and tied in 2011," Texas Public Radio reports.

An excessive heat warning is in effect through 9 p.m. local time in South Texas. Thursday and Friday promise some relief with "cooler" days," the NWS office in San Antonio said — but, it added, temperatures will get "hotter again this weekend through the end of the month."

With parts of Texas seeing record heat this week, James Hand spent Tuesday afternoon overseeing an asphalt resurfacing job at a parking lot in Richardson, Texas. The asphalt has a temperature of 250 to 300 degrees when it's applied, Hand said.

Oklahoma is an emblem of the challenges many areas face as they're whipsawed by extreme weather. First, severe storms struck over the weekend, damaging hundreds of properties and knocking electricity out for more than 341,000 customers by Sunday morning, according to the PowerOutage.us website. At least one person died, officials in Tulsa said.

Then on Monday, the Tulsa area was placed under its first medical heat alert of 2023, according to Public Radio Tulsa, adding that the heat alert would be in effect from Monday "through at least Saturday." As of Wednesday morning, more than 100,000 customers remained without power.

As the solstice arrives, heat index values are soaring past 110 degrees in southern Oklahoma, with only slightly cooler conditions in central and northern parts of the state, according to the NWS office in Norman.

Other areas see excessive rain and cool temperatures

Much of the Southeast faces the risk of excessive rainfall — unwelcome news in communities that have seen record amounts of rain in the past week. It comes amid unseasonably cool temperatures, with highs in some areas 15 degrees below normal as summer officially begins.

A flash flood watch now covers all of northeast Georgia and the western half of South Carolina's upstate region.

"Soils are already primed for floods with last night's rainfall," the NWS office in Greenville and Spartanburg (S.C.) said on Tuesday. "More rain is on the way and will last through Friday."

Many parts of the Plains region will likely see rain and thunderstorms on the solstice, the NWS said, adding, "Large hail and severe gusts will be the main sensible threats generated by any severe storms that develop."

Other areas in the lower 48 states are seeing different extremes, with freeze warnings and even potential snow forecast in northeastern Nevada and southern Oregon, where people were warned of potential damage to sensitive plants and crops.

"Snow in June!?" the NWS office in Medford said on Sunday.

The region is expected to start seeing more normal temperatures on the solstice, but earlier this week, the Oregon towns of Montague and Medford both set new minimum-high records, of 59 and 56 degrees.