Temperatures soared higher than normal across much of the nation in June and through the first six months of 2020, putting the country on track for what could be another one of its warmest years on record.
July could break records in Phoenix after long stretches of hot days and nights. High temperatures have topped 110 degrees 18 times in July at Sky Harbor International Airport and for seven days mid-month, the temperature never fell below 90 degrees.
With Friday morning’s temperature of 91 degrees, Phoenix has posted daily lows of 90 degrees or higher 16 times this year, which would be a record for Sky Harbor.
HOT: At 118 degrees, Thursday heat in Phoenix breaks daily record set in 1934
Every one of the 48 contiguous states saw above-normal average temperatures during the first half of the year, the National Oceanic and Atmospheric Administration reported in its most recent update on climate conditions in the United States and around the world.
The average temperature for the United States, excluding Alaska and Hawaii, from January through June was 50 degrees, 2.4 degrees above normal. It was the eighth-warmest January-to-June period on record.
In Arizona, the year-to-date average daily temperature on June 30 was 57.9 degrees, 2.7 degrees warmer than normal.
That figure includes temperatures from across the state, from Flagstaff to Yuma. The average temperature in Phoenix for January to June was 72.1 degrees; in Flagstaff the six month average was 43.7 degrees. Both were above the long-term average.
The agency expects that trend to continue.
An intense heatwave gripped much of the country in July, and NOAA’s outlook for the next three months shows above-normal chances for warmer-than-normal temperatures.
Of the 48 states, 38 were hotter than normal in June, setting many records and prompting heat advisories from state and federal officials.
In Arizona, this June’s average temperature — 76.7 — was 2.3 degrees warmer than the previous century’s average. In Phoenix, the average temperature for June was 92 degrees, nearly 2 degrees above the average.
Overall, the country was also dryer than normal in June, said Ahira Sánchez-Lugo, a NOAA climatologist.
In the Arctic, a team with the World Meteorological Organization is working to confirm a temperature reading of 100.4 in Siberia in June. If confirmed, it would be the highest temperature ever recorded north of the Arctic Circle, said Randy Cerveny at Arizona State University.
Globally, five of the warmest years on record have occurred since 2015, and nine of the 10 warmest have occurred since 2005.
“The year 2020 is almost certain to rank among the warmest years on record, with a 35.8% chance of it being the warmest year on record,” said Sánchez-Lugo. The chances of the year being the second-warmest on record are above 40%, she said. The combined average temperature over land and the ocean across the globe for the first six months of 2020 was less than one-tenth of a degree from being the warmest first six months of the year on record.
The biggest departures in normal temperatures for the nation for the first half of the year were in the Northeast.
“The entire region was 3 to 9 degrees above normal,” said Jessica Spaccio, a climatologist at the Northeast Regional Climate Center at Cornell University. It was the warmest June on record in Caribou, Maine. Spaccio said it was the third-warmest January to June on record in New Jersey and fourth-warmest in Massachusetts and Rhode Island.
Retiree Leslie Pearce lives just outside Boston in a home her father built in 1976. The unrelenting heat this summer has Pearce considering replacing the home’s window air conditioning unit.
“It’s been awful,” Pearce said. Most people didn’t install central air conditioning when the house was built, she said. “Times have changed.”
In NOAA’s Southwest region, the average temperature was 2.8 degrees warmer than the mean over the previous century, making it the 11th-warmest January to June on record.
Florida is enduring its warmest year on record.
Conditions have been “just off the charts,” said Brian McNoldy, a senior research associate at the University of Miami’s Rosenstiel School of Marine and Atmospheric Science.
In Miami and Key West, “from one hour to the next, meteorologists are looking to see what record has been broken,” McNoldy said. “It’s hard to keep up with, either some record for the day, for the month, for the year or the year to date. It’s a never-ending stream.”
Other coastal towns throughout the Southeast are experiencing one of their warmest years on record, including New Orleans, Savannah and Cape Hatteras. “With the continued upward trends we’re seeing, it just makes it that much harder to be ‘normal,’ and it makes it that much easier to break record highs because you’re off to kind of a head start.”
Part of the reason for those warm temperatures is likely the warmer-than-normal sea surface temperatures, McNoldy said. That may be especially true in the warm overnight lows.
“Rather than being able to fall to 76 or 77 degrees at night, if you’re surrounded by an ocean that’s 85 degrees, there’s no way you’re going to cool off that much,” McNoldy said. “And, if the sun comes up and it’s already 84 degrees, you’re just going to go up from there.”
Overnight lows experienced a similar trend, with all of the 48 states averaging at least 1.4 degrees warmer than normal. Nightly minimum temperatures in Connecticut, Massachusetts and New Jersey were 4.5 degrees warmer than the normal average.
In Arizona, the average minimum temperature so far this year was 43.3 degrees, 2.5 degrees warmer than normal. In Phoenix, the average low was 59.9 degrees for the first half of the year, and 79 degrees in June.
So far, the average nighttime temperature in Phoenix during July has been 87.8 degrees. The average temperature over 24 hours has been over 100 degrees on 16 days during July.
WHAT’S UP?: Why Phoenix is setting records for nighttime temperatures
Across the country in June, record warm daily low temperature records were set 3,181 times.
The hotter weather has taken a deadly toll. Through July, for example, Maricopa County had already confirmed six heat-related deaths and officials were investigating 151 additional deaths where heat is suspected. The nation averages 702 heat-related deaths a year, according to the Centers for Disease Control and Prevention, and scholars expect that number to rise exponentially as temperatures continue to warm.
It no longer surprises Marshall Shepherd, former president of the American Meteorological Society and director of the atmospheric science program at the University of Georgia, to hear heat records are being broken.
It only underscores the critical issues with climate change, he said, such as “how resilient the nation is and how vulnerable populations are going to continue to bear the brunt of this heat and extreme rainfall events.”
The Arizona Republic contributed to this report.