Severe weather possible this week with thunderstorms, small hail

Powerful thunderstorms and near record-high temperatures are forecast through Wednesday as the sprawling tail of a cold front whips into South Florida.

Small hail, wind gusts up to 60 mph and frequent lightning are the main concerns with the forecast, which puts Palm Beach County and the Treasure Coast in the marginal threat level for severe weather Tuesday and Wednesday.

While marginal is the lowest level on a five-tier scale, increasing moisture, and a dip in the jet stream that places South Florida under the swift-moving current of air, could make for potentially volatile storms.

Top lightning myths debunked.

“With the warm humid air building, all we need is for the cold air aloft and strong winds aloft to interact with that to cause severe weather,” said Dan Kottlowski, a senior meteorologist with the Pennsylvania-based AccuWeather. “That’s why we believe that Florida is looking to be primed for that potential.”


The Storm Prediction Center in Norman, Okla., gave South Florida a 5 percent chance of severe weather as of Monday.

Tuesday’s temperature could hit 90-degrees, just one degree shy of the record set in 1986. Expected cloud cover could limit Wednesday’s high to 87 degrees.

Afternoon sea breezes are the expected trigger for Tuesday’s storms, which are forecast to mostly hug parts of the coast.

By Wednesday afternoon, the cold front associated with a low pressure system centered over the mid-Atlantic states will swing into South Florida. Speedy winds high in the atmosphere coupled with temperatures of just 14 degrees near 18,000 feet could mean robust updrafts, which are the makers of hail and lightning.

“We’ll assess as we go,” said Robert Molleda, warning coordination meteorologist with the National Weather Service in Miami. “Wind and hail appear to be the two biggest threats, but we can’t rule out anything else.”

The cold front will bring in drier air and force temperatures down a little. Thursday’s high is expected to reach 83 degrees, which is about normal for this time of year. Friday’s daytime temperature will climb only to 80 degrees, four degrees shy of normal.

Some rain will likely be welcomed by parts of parched Palm Beach County, which ended April below normal for rainfall.

An average of just one inch of rain fell last month in coastal areas of Palm Beach County, according to the South Florida Water Management District. That’s two inches below normal for April.

Rain chances Tuesday stand at about 50 percent, increasing to 70 percent Wednesday.

“The timing for this couldn’t be worse for the Palm Beaches,” Kottlowski said about Wednesday’s storm forecast. “It looks like all the ingredients are coming together during the mid to late afternoon hours.”



Storm Prediction Center forecast for Tuesday.