ST. PETERSBURG — Ben Daniele stood outside his video production company's office space on Central Avenue with his hands plunged deep into his pockets.
"It's cold," the 35-year-old said as he bounced up and down, trying to stay warm.
But was it really? Lows in Tampa Bay on Friday were in the early 40s. To the Ohio native, that sounded warm — or at least it would be if he was back in his hometown of Cleveland, which was 9 degrees that same day.
Now, he said, 42 degrees feels down right frigid.
"I feel like my body has to have physiologically changed," he said. "I feel different now when I go up north."
The first cold snap of 2018 has left transplants like Daniele wondering: Do Floridians truly get "thinner blood," or is there something about a rare Florida chill that just feels colder?
Doctors and meteorologists agree it mainly comes down to how bodies acclimate to climates — but there are other factors at work, too. There can be circumstances when Florida's humidity does, in fact, make it feel colder than what the thermostat reads.
It's a mixture of temperatures, the moisture in the air and the human body's efforts to keep its core temperature steady, experts say.
Think of the hypothalamus, deep inside your brain, as a thermostat that resets itself around a new climate, said Dr. Tim P. Carlson of Palms Primary Care in St. Petersburg.
"Your hypothalamus performs a range of invaluable roles," he said, "and helps steady your core temperature, usually around that surrounding environment."
Rain preceded this week's chilly blast, meaning there were high dew points that made the region's first taste of the cold feel colder, said National Weather Service meteorologist John McMichael.
"That's what they experience in England," he said. "That's the kind of cold that goes right through you."
Exacerbating the cold were strong wind gusts of 20 to 25 mph, which died down later in the week.
By Friday, Tampa Bay's dew points were as low as they are this time of year up north. Yet, Floridians were still shivering.
Carlson said it usually takes about five days for someone's internal thermostat to reset — so anyone used to Florida's tropical climate would have a hard time quickly adapting to the sudden jolt in temperature.
"If it's just minimally cool then a nice jacket would be ample," Carlson said. "If you have a wind chill, then our bodies are going to react pretty quickly."
And if you're not used to the cold, those reactions will begin sooner: The hairs on your arms stand up, muscles will tighten, blood vessels narrow.
The cold can cause serious problems for Florida's aging population, who have a harder time adapting to sudden temperature changes.
Carlson spent part of his Friday checking on elderly patients at a retirement center. That morning alone he saw 12 people with severe colds. The doctor warned that elderly residents should stay hydrated and layer up.
"All these things people don't think about," he said, "but there's a lot of affects of the cold on the body's systems."
Thankfully, forecasters say warmer days are near.
The high on Monday is 74 degrees.
Contact Sara DiNatale at firstname.lastname@example.org. Follow @sara_dinatale.