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As chestnuts roast, we toast

By CRAIG PITTMAN
Published January 3, 2007


If you thought Christmas and New Year's Eve seemed a little on the warm side, even for Florida, you were right.

While other parts of the country were still digging out from blizzards, the National Weather Service announced that last month was the warmest December in the Tampa Bay area in 75 years.

Above-normal temperatures should continue the rest of this week. And because of a combination of global weather factors, the next three months are unlikely to ever get very chilly.

"We just haven't had much in the way of arctic air," said state meteorologist Ben Nelson.

Temperatures in the final three days of December were 10 to 15 degrees above normal throughout Central and southwest Florida.

New Year's Eve tied the record for the highest high temperature in Tampa Bay area history, at 83 degrees. The low temperature on New Year's Eve was the warmest ever for that date - 71 degrees, breaking a record that had been on the books since 1900.

Christmas Eve was equally warm, with a record-breaking high of 83 degrees. The highest high for the month in the region was Dec. 17, when the mercury hit 84 degrees.

Put all the highs for December together and average them out, and the result shows that last month was the warmest since the record was set in 1931, forecasters said.

"We had basically two cool fronts, one on Dec. 6 and 7, and it was still a little chilly on the 8th, and one right after Christmas, after the tornadoes," said Barry Goldsmith, a meteorologist with the National Weather Service in Ruskin. "Take one of those away, and we would probably be rivaling the record."

Part of the reason for such unseasonable highs is El Nino, a warm current of water that appears every three to seven years in the eastern Pacific Ocean, shifting weather patterns around the globe.

Because El Nino pushes the subtropical jet stream over Florida, it tends to produce warmer Decembers, said Daniel Noah, another weather service meteorologist from the Ruskin office. The jet stream blocks cold air from the north from getting into Florida, he explained.

Usually an El Nino produces chillier than normal temperatures in January, February and March in Florida, Noah said. But climate experts are predicting instead that Florida temperatures will be normal for the next three months.

"This hasn't been a typical El Nino," Nelson said.

That's because of a competing weather pattern called the North American oscillation, he said.

The North Atlantic oscillation drives surface winds and wintertime storms from west to east across the North Atlantic, affecting the climate from New England to Western Europe and southward to West Africa.

In Florida's case, the weather pattern "is keeping us locked in a pattern of warmer temperatures," Nelson said.

All that warmth doesn't translate into more rain, however. Even though the central and southern parts of the state need rain desperately, he said, "the storm tracks are all staying just north of the part of the state that really needs the rainfall."

SOURCE: National Weather Service