The National Weather Service is forecasting temperatures near 90 and afternoon storms in West Palm Beach today, but things heat up even more Wednesday ahead of an unusually late cool front.
Wednesday’s daytime high could be a scorching 94 degrees.
That’s abnormal even for August in South Florida and a full seven degrees above what’s normal for May 24. The record high temperature for the day is 96 degrees set in 1917.
The late May cool front, which is likely the last of the year, will be switching the winds to the south-southwest on Wednesday, sucking up deep tropical moisture and turning up the heat.
Parts of Palm Beach County from Jupiter southwest to suburban Boca Raton, and including west to Lake Okeechobee, are under a slight threat of severe weather. That means a moderate threat of damaging winds 60 mph or greater, hail up to quarter size and isolated tornadoes.
While the exact timing of the turbulent weather is dependent on how swiftly the front advances, meteorologists were forecasting Wednesday afternoon into Thursday as its likely window of opportunity.
“This is more than the normal Florida thunderstorm,” said Kenneth Clark, an expert meteorologist with AccuWeather. “It’s out of the ordinary kind of stuff because it’s late for something to get this far south.”
And it has an extra spark — a screaming jet stream running at 150 mph over Florida is forecast to smack into deep tropical moisture flowing in from the south-southwest. That warm, buoyant air rising quickly into cold air aloft can cause combustion in the form of thunderstorms.
It also has the making for hail if thunderstorm updrafts are strong enough to suspend raindrops in the upper atmosphere long enough to freeze.
“It’s probably the last front of the year of this magnitude,” said Tim Sedlock, a meteorologist with the National Weather Service in Melbourne. “It has some upper-air support and that’s somewhat unusual for this time of year. We’ll also have deeper moisture across the area with higher precipitation rates.”
Rain chances Wednesday are 40 percent increasing to 70 percent in the evening.
The Weather Prediction Center has southeast Florida getting between 0.50 inches and 1.25 inches of rain Wednesday into Thursday. But meteorologists don’t believe flooding will be a problem because the ground is so dry.