COLUMBUS, Ohio (WCMH) – Average temperatures in Columbus were 2.4 degrees Fahrenheit above normal this autumn, tied for the 10th-warmest meteorological fall in the capital city’s history.
Most major weather stations in Ohio saw a fall among their top ten hottest this past September through November, while northern cities like Akron, Findlay and Toledo nearly hit records.
|Ohio city||Rank: Avg. daily temp. in Fall ’21||°F above normal|
|Akron||T-2nd-warmest (131 years)||+3.2°F|
|Toledo||3rd (149 years)||+2.7°F|
|Findlay||4th (79 years)||+1.7°F|
|Zanesville||4th (75 years)||+1.9°F|
|Mansfield||8th (101 years)||+2.6°F|
|Cleveland||9th (149 years)||+1.6°F|
|Youngstown||9th (94 years)||+2.7°F|
|Columbus||T-10th (144 years)||+2.4°F|
|Dayton||T-11th (129 years)||+1.7°F|
|Cincinnati||T-29th (150 years)||+1.9°F|
Ohio’s warm autumn was driven by an unusually hot October that bumped up average temperatures and set records for daily lows, said NBC4 meteorologist Liz McGiffin.
“One of the first things that people may have noticed is that the fall foliage took forever to change, it felt like,” she said.
One of cues that leaves look for to change color is a consistent transition to cool, crisp nights. But warm October nights contributed to delaying leaves’ peak fall colors by 2-3 weeks in central Ohio.
“So, that was one of the really visual signs,” McGiffin said of the warm fall, “And another thing, too, is when we got that first snow, it melted right on impact because we had been so warm.”
Seven major Ohio cities saw their warmest-ever average low temperatures for October, including Columbus (+9.1°F), Zanesville (+9.5°F), and Akron (+9.9°F).
In 144 years of recordkeeping, this autumn ranked as Columbus’ ninth-warmest for average low temperatures. It tied at 23rd-warmest for average high temperatures.
Climate change connection
So far this year, average daily temperatures in Columbus have been 1.2 degrees above normal, tying for the city’s 12th-warmest year on record so far. This continues a trend of hotter seasons linked to changes in weather and climate seen in the Great Lakes region and the rest of the world.
As humans emit more greenhouse gases like carbon dioxide, methane and nitrous oxide into the atmosphere, it traps more heat. This climate change warms average air and ocean temperatures, and because a warmer atmosphere also holds more water, it causes more rain to fall.
“When you think back to even 10 years ago,” McGiffin said before Wednesday’s snowfall, “you may not have memories of this late in the season going out to mow your grass, because we’re still dealing with rain instead of snow in the forecast.”
Warmer fall temperatures now and in the future, she said, are pushing back “that first killing freeze” that ends the growing season and pushes away mosquitos and allergies for the year.
“The longer it takes for us to get cold,” McGiffin said, “that means that we could even be setting ourselves up for less snowpack as we head into the winter months.”
More warmth forecasted for December, winter
The National Oceanic and Atmospheric Administration predicts winter across Ohio will likely be warmer and wetter than average as a La Niña pattern moves from the Pacific Ocean to the U.S. mainland for the second straight year.
The cooler ocean surface temperatures of a La Niña impact the jet stream, which flows eastward along the U.S.-Canada border. While Upper Midwest states like Minnesota and the Dakotas may have colder temperatures, more southern states – like Ohio – will see a warmer December through February.
“The next couple of months, it doesn’t mean that every day is going to be 60 degrees,” McGiffin said, but it will extend the trend of “more days than not being continuing to be warmer.”
With a La Niña pattern last winter, NOAA data shows Columbus’ average daily temperatures were slightly warmer than average at 0.5 degrees above normal.
Looking back decades, however, a Climate Central analysis published last month found winter in Columbus has warmed 4.5 degrees since 1970, with winters now seeing 11 more days warmer than normal in the last half-century.