Last month was hottest in more than a century
BY KIMBERLY MILLER
A steadfast carousel of high pressure over Florida last month led to the warmest May in more than a century with an average temperature nearly four degrees above what’s normal for the fifth month of the year.
At 78.8 degrees — 3.7 degrees hotter than normal — May in the Sunshine State earned the top spot for record heat in measurements that date back to 1895, according to a report released by the National Oceanic and Atmospheric Administration.
Florida was the only state in the contiguous United States that ranked hottest in May, but Southeastern states from Alabama to Maryland recorded above average warmth as the same area of high pressure cleared away springtime clouds.
Hundreds of tornadoes
Florida climatologist David Zierden said the May heat was more of a weather phenomenon than something tied to climate change.
“It was just a stubborn deep layer high pressure system that set up over us and was very persistent for two or more weeks,” Zierden said. “We had warm high pressure here and troughing in the west and a battleground in between where there was all the severe weather.”
More than 500 tornadoes were reported in May nationwide. That’s more than double the three-year average of 226 and the most active 30-day tornado period since 2011.
How cities fared
At least seven Florida cities simmered through last month with their highest May temperatures, including Jacksonville, Gainesville, Tallahassee, Melbourne, Punta Gorda, Sarasota and Orlando.
Weather Service figures show Jacksonville with an average monthly temperature of 78.4 degrees with a maximum high of 100.
“We were basically just in a quieter pattern where we had a good ridge of high pressure that was located somewhere in our vicinity over a portion of that time,” said Sean Miller, a meteorologist with the National Weather Service in Miami.
“A lot of times when we have high pressure set up we get an easterly flow which can cool it down a little bit so we might not have been as warm as other areas.”
More rain elsewhere
Miller said a lack of robust cold fronts was to blame for a warm winter.
“We had a decent amount of fronts, but no really strong ones, or very few strong ones,” he said. “We just stayed a little further way from the higher mid-latitude weather that brings us the cooler intrusions.”
Nationwide, May was marked more by rain than heat.
The National Centers for Environmental Information, which issues the monthly NOAA weather summary, said last month was the second wettest May on record and the second wettest month of all months since January 1895.
The national average May rainfall was 4.41 inches, about 1.5 inches above normal.
Although a hefty early-May deluge left South Florida flush with rain for the month, including 6.27 inches in coastal Palm Beach County, North Florida is suffering from drought.
Dry in Panhandle
The U.S. Drought Monitor report released last week showed most of the Panhandle in a moderate drought or with “abnormally dry” conditions.
“This is what they call a flash drought,” Zierden said. “It came on very suddenly.”
Zierden said there has been no measurable rainfall in Tallahassee for about 18 days with high temperatures in the mid to upper 90s.
“Things dried out very quickly,” he said.