Brace yourself: Cold, then rainy and more cold as systems collide

6:01 a.m. Thursday, Oct. 26, 2017 Weather
National Hurricane Center

A soggy weekend might be ahead for South Florida with the collision of a simmering tropical system and a second forceful cold front.

While timing is key in this dance of opposites, as much as 3 inches of rain is possible in Palm Beach County beginning Saturday morning into Monday. Higher amounts nearing 5 inches were forecast as of Wednesday for areas of Broward and Miami-Dade counties.

The season’s second cold front will hit South Florida on Sunday and bring temperatures in the 70s in Palm Beach County early next week.

The weekend’s wet weather would follow the season’s first cold front that washed through Wednesday, leaving the daytime high struggling to reach 76 degrees and dropping this morning’s temperature to a forecast 55 degrees in West Palm Beach.

DON’T RELAX YET: Florida remains vulnerable to hurricanes through October

If that forecast of 55 holds true, it’s a full 15 degrees below normal for this time of year and nearing the record low of 52 degrees set Oct. 26, 2010.

“There’s a pretty high confidence at this point that we’re going to see a lot of rain,” said Andrew Hagen, a meteorologist with the National Weather Service in Miami. “The heaviest rains will be farther south, but I think 2 to 4 inches across South Florida is possible.”

The National Hurricane Center was giving the tropical disturbance bubbling in the southwestern Caribbean just a 40 percent chance of development during the next five days. Dubbed Invest 93L, it would be named Philippe if it gained tropical storm strength.

David Zelinsky, a specialist at the National Hurricane Center, said the system’s interaction with Nicaragua and Honduras is inhibiting development, but as it begins a slow trek north, conditions become more favorable for some organization.

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“In another day or two, it’s going to move, and we think there may be a 48-hour window or so when it could develop a little,” Zelinsky said. “It will move north and then east as the front approaches. What is less clear is exactly what form it will be when it does that.”

It’s not unusual for a hurricane to spin up in late October. In 2012, Sandy became a hurricane on Oct. 24, slamming into New Jersey as a post-tropical cyclone with hurricane-force winds five days later. Hurricane Wilma’s Category 3 landfall near Cape Romano occurred 12 years ago Tuesday. In 1998, Mitch reached hurricane strength on Oct. 24, building to a Category 5 storm two days later. Mitch hit near Fort Myers on Nov. 5 as a tropical storm.

But forecasters said there’s no indication 93L will be a Sandy, Wilma or Mitch.

Hagen said he doubts it could even reach to a moderate or high-end tropical storm.

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“We can’t completely rule out a weak tropical storm, but wind shear is going to keep it from getting too strong,” Hagen said.

The system’s northerly path will bump it into that second cold front that is forecast to drape across the Gulf of Mexico on Saturday morning before pushing through South Florida on Sunday.

The weekend cold front is from a deep undulation in the jet stream caused by former Typhoon Lan in the North Pacific. It’s the same atmospheric wave responsible for the 100-plus temperatures at Tuesday’s World Series game in Southern California.

Behind the front, temperatures early next week in Palm Beach County should top out in the mid to high-70s, and fall into the 60s overnight.