It’s a good bet that 2020 will accomplish what the last four years narrowly failed at – beating 2015 as the hottest on record in Orlando and Florida.
Keeping pace with a roasting planet swaddled in greenhouse-gas pollution, Orlando’s average temperatures for 2016, 2017 and 2018 are among the 10 warmest on record; 2019 is the second warmest. Records for the city and state go back to the late 1800s.
The annual average figure is calculated from the average of daytime highs and nighttime lows. Orlando’s average temperature was 75.6 degrees in 2015, 75.2 degrees in 2019 and is 77 degrees so far this year.
State climatologist David Zierden said Florida’s average temperatures for the last 65 out of 68 months, including the last 28 in a row, have been above normal.
“That’s not luck of the draw,” Zierden said. “The background climate is definitely changing.”
The warm-up is encompassing days, nights, summers and winters.
Orlando has recorded a single, freezing night since 2015: 27 degrees on Jan. 18, 2018. Late into the last century, freezes commonly occurred several times a year. There were multiple freezes in 2010, which were delivered by repeated cold fronts from January to March.
“That was our last harsh winter,” said Zierden, who expects repeats to be increasingly rare. “It’s still the atmosphere. We still have natural variability. We still have big weather events. I’m not ready to say those cold winters are a thing of the past, but it’s going to be less frequent and less likely.”
In Central Florida, plenty of records were broken this year for daytime high temperatures, while nearly twice as many records were broken for warm nights — or the warmest low temperature of a night.
The high ratio of record-warm nights turns up in monthly reporting by Derrick Weitlich, meterologist and climate program leader for the National Weather Service office in Melbourne.
In January, Orlando had four nights that were the warmest on record and one daytime record: Jan. 12 hit 86 degrees.
By the start of spring, Central Florida was sizzling.
“The intense and unrelenting warmer pattern generated monthly average temperatures that were around 5 to 8 degrees above normal, and also ranked as the warmest on record for March at Daytona Beach, Leesburg, Sanford and Orlando,” Weitlich reported.
Orlando’s summer didn’t let up and August was the city’s fifth-warmest, with five nights measured as the warmest on record and three nights tying records.
The nighttime temperature on Aug. 25 dropped to only 80 degrees. That tied the warmest night on record for all of August, matching the mark set Aug. 19, 1909.
September was the ninth-warmest and October was the third warmest on record for Orlando.
October had two nights measuring as warmest on record, with low temperatures of 75 degrees on the 20th and 27th, topping records set for those nights last year.
Weitlich said if the rest of the year cools off to normal temperatures, 2020 would still be on track to tie with 2015 as the warmest on record. Even with cooler-than-normal temperatures, there’s a “high likelihood” the year will finish in the top three warmest.
The expected consequences of the steady rise of global and local temperatures include destructive rises in sea levels, more powerful storms, extreme shifts between flooding rains and prolonged drought and more.
But the price of a warming climate is readily observed already, including by farmers, ecologists, power-plant operators and most everybody else.
Mangroves are spreading from their South Florida strongholds to along the coasts of North Florida.
The exotic and invasive Brazilian pepper trees, not hardy enough to tolerate cold weather, are sprouting inland in Central Florida, including along the conservation lands of north Lake Apopka.
Roger Kjelgren, director of the University of Florida’s Institute of Food and Agricultural Sciences Mid-Florida Research and Education Center near Apopka, said warming temperatures have changed urban suburban scenery.
“I see it in my own front yard and you can see how it has changed the residential landscape with tropical foliage,” Kjelgren said.
He cited, as an example, papaya that “with its papery leaves will get knocked back hard” with a freeze.
Another common landscape plant is allocasia, sometimes called giant taro or elephant ear.
Any temperature 32 degrees or lower will kill the plant to the ground, Kjelgren said. “Seeing large ones around town means we haven’t gotten below freezing for a few years.”
kspear@orlandosentinel.com
