Forty-five years ago this week, the polar jet stream twisted into a raging river of powerful winds sweeping south over the warm Gulf of Mexico and into South Florida where climate history was made.
On the morning of Jan. 19, 1977, snow fell in Palm Beach County.
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The snow that day had an icy reach as far south as Homestead Air Force Base -- the farthest south snow has been recorded in the contiguous U.S. It spread west to Freeport on the island of Grand Bahama, which is the only instance of snow being observed in the history of the Bahamas, according to the Florida climate Center.
Previous to Jan. 19, 1977, the farthest south snow had been seen was along a line from Fort Myers to Fort Pierce in February 1899, according to the National Weather Service in Miami.
The snowfall was not a complete surprise to forecasters. It had been a bitterly cold for few days with a front passing through on Jan. 16, followed by a second front two days later. Record-low temperatures were expected, freeze warnings had been issued and spotty rain had meteorologists warning of icy roads.
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Records kept by the National Weather Service in Miami show the first snowfall at Palm Beach International Airport was observed at 6:10 a.m. on Jan. 19.
Joe Vidulich was a 27-year-old meteorological technician at the federal weather office then stationed at the airport. He said he was working the midnight to 8 a.m. shift on Jan. 19, and while snow was expected in Central and North Florida, he didn't think it would make it to Palm Beach County and beyond.
"I went outside to take an observation and I noticed these particles flying by. At first I thought they were bugs, but it was snow," Vidulich said. "I ran back inside so excited and my partner was sleeping in a chair. I said, 'Wake up Bernie, it's snowing.' He said, 'You must be drunk.'"
Vidulich sent a special alert via Teletype -- the first snow recorded in West Palm Beach.
Climatologically, it is not supposed to snow in South Florida. The laid-back tropics are a region constantly gaining energy from the sun, and with Florida's temperatures moderated by warm water on three sides, snow is unusual even in northern reaches of the state.
But in January 1977, all the ingredients for frozen precipitation came together. The high pressure near California forced a mountainous ridge into Canada and a deep trough to dig through Florida, which funneled arctic air south. While winds at the surface were blowing from the north behind the cold front, winds high in the atmosphere at 5,000 feet were out of the west. That westerly wind picked up moisture from the Gulf.
At the same time, the freezing level in the atmosphere was at 1,500 feet above sea level, which is low for South Florida and kept the snow from melting before it hit the ground.
This article originally appeared on Palm Beach Post: Snow fell in South Florida in 1977: Remembering climate history