Tuesday’s robust thunderstorms spun up waterspouts, dumped marble-size hail, and sent more rain to Palm Beach County in 24 hours than during all of March.
The storms preceded a late-season cool front that dragged drier air and sunshine into South Florida. Clear skies are expected into Friday when rain chances pick up to 30 percent.
With the potent winter up north finally giving way to more spring-like weather, Tuesday’s cool front may be the last before the rainy season starts in May.
But it was a memorable one.
Four reports of hail in Martin County were recorded by the Storm Prediction Center, including ice chunks the size of quarters in Tequesta. The National Weather Service in Miami also said a trained weather spotter saw hail in Atlantis and Lantana. Video from Jupiter Inlet shows pea-sized hail bouncing off a balcony.
“I’ve been living in this town 50 years and I’ve seen hail before, but I’ve never seen as much hail as I did yesterday,” said Tom Knapp, who lives just north of County Line Road in Tequesta. “You could have gotten a sled and slid down my front lawn there was so much hail.”
The following videos were taken by Knapp’s son, also named Tom, near the Jupiter Inlet. They show small hail and a palm tree that is smoking after being struck by lightning.
Lake Worth received the highest amount of rain at 3.16 inches, with Boynton Beach as runner up with 2.7 inches.
Most of coastal Palm Beach County got just 0.53 inches of rain in March, which was 3.03 inches less than what’s normal for the month, according to the South Florida Water Management District.
Before Tuesday’s rain, coastal Palm Beach County was down nearly 4 inches since Jan. 1, with the 16 county region overseen by the South Florida Water Management District at an average 3.92-inch deficit.
The storms were particularly strong because they hit near peak warming of the day with a very cool upper atmosphere.
Thunderstorms produce hail if they have a particularly strong updraft that can suspend rain droplets in the freezing upper reaches of clouds. The size of the hail depends on the strength of the updraft – stronger updrafts can suspend frozen water droplets longer, allowing them to grow.
How much melt occurs as the hailstones fall to earth also impact size.
While hail is unusual in South Florida, it does happen.
Since 1976, there were 86 days in Palm Beach County where hail was reported.
What’s more rare is large hail. Since 1980, Palm Beach County has seen hail with a diameter of 1.75 inches (about golf-ball size) just 14 times, according to the National Weather Service’s Storm Events Database.
The most recent occurrence on record was on Feb. 24, 2010, when a trained weather service spotter recorded large hail west of Palm Beach International Airport during a thunderstorm that included 40 mph winds.
In late March 1996, hail damaged at least 100 vehicles at the airport and decimated a 60-acre cucumber field, according to the database.
Waterspouts were also spotted off Palm Beach County and in the Florida Keys from Tuesday’s storms.
South Florida’s rainy season typically begins in mid-May, so the really wet weather is still a few weeks away.
While Tuesday’s storms will help lessen drought conditions, they won’t be reflected in tomorrow’s report, which gathers data only through 8 a.m. the Tuesday before release.
This is the drought monitor map from April 19.