An astounding 26 inches of rain fell in Fort Lauderdale on Wednesday, with most of that falling in just seven hours, according to the National Weather Service.
The shocking deluge could break multiple state and even national records for rainfall, once all is said and done. “It was an unprecedented event,” said Shawn Bhatti, meteorologist with the National Weather Service in Miami.
He said that preliminary data on Thursday indicated that there were pockets of Fort Lauderdale, stretching from Fort Lauderdale-Hollywood International Airport up to Edgewood, Tarpon River, and south of the upper Middle River, that were drenched with 20 to 25.91 inches Wednesday, and the broader metro area was pummeled with 10 to 15 inches of rain.
Incredibly, most of that rain fell in a six- or seven-hour period, with some stations reporting up to 20 inches in that time frame. This was on top of several previous days of rain.
Those 24-hour totals have a 1-in-500 chance of happening in any given year, and the six-hour totals have a 1-in-1,000 chance of happening in any given year.
AccuWeather Chief Meteorologist Jonathan Porter said that based on preliminary observations, the 25.91 inches that fell in 24 hours at a location in Fort Lauderdale, if confirmed, will break the all-time Florida record for 24-hour rainfall. The current record is 23.28 inches, which fell in Key West on Nov. 11, 1980.
He said, “It appears that about 1.5 inches of rain occurred in 10 minutes in Fort Lauderdale — which is close to the United States all-time record for rain in that short period of time.”
The rainfall was so intense, he said, that the visibility reported at Fort Lauderdale’s airport was akin to a blizzard. “Multiple times during Wednesday afternoon (the visibility) was 1/8 of a mile — the type of low-visibility report that is typical in cases when very heavy snowfall is occurring and rarely reported with rainfall.”
The dynamic weather also triggered two tornados, the NWS confirms — one west of Dania Beach, just north of Sheridan Street at around 3:30 in the afternoon. It lasted only a minute, and had 65 mph winds. The second twister formed in Dania Beach just south of the Fort Lauderdale-Hollywood International Airport at around 9:40 p.m. and traveled half a mile over the course of three minutes.
A stack of moisture
How did this happen? “The best way to explain it is that winds steer storms and moisture. In the lower 1-3 km (of the atmosphere) we had east-southeast flow with really good moisture coming off the Atlantic water. Then we had good southerly flow in the mid-levels, and above that we had westerly wind.”
He said there was unusually high amounts of moisture stacked high into the atmosphere.
“There was a very deep moisture profile. With atmospheric moisture, we’re not just concerned with moisture at the surface, we’re looking through the whole column of the atmosphere,” which extends 10-11 km in this area.
There was a lot of moisture throughout the column, he said. The boundary layer, near the water surface, was saturated, but that saturation continued up about 3-5 km.
As for the mechanics of the storm, “It’s not like a tropical storm,” he said. “It’s a series of storms that develop within a favorable environment.”
Bhatti warned that today there will be more rain, but it will be more isolated than Wednesday, and along the coast, where the flooding occurred Wednesday. “It’s going to be one of those days where some locations get 2 to 4 inches or rainfall, and other locations don’t get anything.”
The weather service has issued a flood watch through 8 p.m. tonight in the Fort Lauderdale area.
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