Spring came early to South Florida. Way early.
When February ends Wednesday, the average temperature for the month is expected to hit 76.4°F, said University of Miami Rosenstiel School of Marine and Atmospheric Science researcher Brian McNoldy. That’s more than six degrees hotter than a typical February, and 1.5 degrees warmer than the previous record — a staggering lead in weather records normally broken by hundredths or tenths.
“This is just way out of the norm,” McNoldy said. “We’re basically two months ahead of par in terms of temperatures. That’s crazy.”
Or to look at it another way: The same temperatures in March would rank as the fourth hottest on record.
“When you can break the next month’s records too,” he said, “that’s pretty high.”
What’s driving the high temps is the lack of seasonal cold fronts. Normally South Florida gets blasts of winter weather as low pressure troughs allow chilly temps to roll through. But a high pressure ridge has been parked over much of the eastern U.S., blocking fronts and keeping temperatures high over the eastern third. It’s not clear why the ridge is stuck, McNoldy said.
“When the whole ridge-trough pattern gets plugged up, it typically affects a decent chunk of the hemisphere and you’re either stuck in one or the other,” he said. “And we’re stuck.”
The high temps have also left ocean waters warmer than normal, a troubling sign in the wake of recent algae blooms and seagrass die-offs that killed seasonal tourism and left the fishing industry struggling long before Hurricane Irma hit. On Tuesday, water temperatures off Virginia Key hovered between 77 and 79 degrees. Temperatures typically average 72 degrees in February and don’t reach the upper 70s until April and May.
In Whipray Basin in Florida Bay, where 60 square miles of seagrass died in 2015 and 2016 and Irma dumped vast mats of dead grass in September, water temps were between 77 and 81 degrees this week. They should be 71 degrees. Scientists have already warned that the dead grass could trigger more blooms.
February’s heat comes on the heels of a record hot year that tied with 2015 for the warmest on record and swung wildly from one extreme to another. During the winter, extreme drought sparked wildfires and led to a state of emergency. By spring, the wettest rainy season to hit South Florida in 86 years left many areas struggling with flooding.
While a warming planet is likely to see more records broken, McNoldy said localized weather events like February’s high cannot be blamed on climate change.
“As the baseline warms up, it’s just easier and easier to break these warm records and harder to break cold records,” he said. “And we’ve seen that. We hardly ever break cold records.”
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