A series of hearty arctic blasts in January “without a doubt” broke Florida’s nearly two-year fever of warmer than normal monthly temperatures — a notorious heat streak that began in March 2016.
Preliminary measurements from the Southeast Regional Climate Center show last month’s statewide average temperature through Tuesday was 57.4 degrees. That’s just slightly below the 122-year average of 57.7, but enough to end the stretch of warm months that helped put 2017 in the record books as the runner-up for hottest year on record. Holding at first place for Florida’s warmest year is 2015.
“Without a doubt, the statewide temperature ranking for January will end up below normal,” said Florida Climatologist David Zierden, who noted that the streak would have been longer if not for two standouts in 2016. “The last 32 out of 34 months have been above normal, with only February 2016 tying the average and January 2016 below average.”
The reason last month’s average temperature was only slightly below normal was likely because of a see-sawing weather pattern that sent temperatures plummeting as the jet stream dove into Florida and shooting back up in its wake.
“This is more typical of what we would think Florida would be like in winter months,” said Robert Molleda, the warning coordination meteorologist for the National Weather Service in Miami. “We get cold air masses that make it down, move out, and then there’s a warming trend ahead of the next system.”
That was evident at the Palm Beach International Airport official weather service gauge where the first week of January averaged temperatures up to 19 degrees below normal, while the second week had above normal temperatures that were as much as 11 degrees warmer than the historical average.
The coldest temperatures were 38 degrees on Jan. 4, and 39 degrees on Jan. 18. No temperatures below 40 were recorded in 2016 or 2017.
“We really have to go back to the winter of 2015 to get something that resembles a true winter,” Molleda said.
Some areas in Florida saw temperatures last month that ranked them in the top 20 coldest Januaries on record, including 15th ranked Tallahassee, which got measurable snow for the first time in nearly three decades on January 4. Jacksonville had its 17th coldest January. Sarasota was 19th coldest.
West Palm Beach had its 52nd coldest January. As of Tuesday, it was 0.1 degrees below normal for the month, but may end up just at normal or even slightly above, Molleda said.
With a La Nina climate pattern influencing weather conditions, the Climate Prediction Center forecast a 40 to 50 percent probability that temperatures would be above normal for Florida this winter, which includes December, January and February.
“We are just talking about a possible range in these longer-term outlooks,” Molleda said. “We can tell fairly well over 5 to 7 days whether temperatures will be above or below normal, but as you increase that, it’s more difficult.”
December ended 3.1 degrees warmer than normal. With January just slightly below normal, February will decide whether the center’s long-term forecast holds true.
“We’re kind of off script a little bit,” Zierden said last month. “But we still have to look at the season as a whole before we decide if the forecast was wrong.”