It’s been a dry year — most of the region has been in either severe or extreme drought conditions since early spring.
But as of Monday, there’s only a small sliver of northeastern Palm Beach County that remained in moderate drought for the year to date.
South Florida has benefited from a shift in the prevailing winds that allows thunderstorms to soak the east coast instead of the west coast of the state.
“It is much less (of a dry area) than it was a couple weeks ago and even a few months ago,” said Sammy Hadi, a meteorologist at the Miami office of the National Weather Service.
The slow tropics have not been a factor in the drought, Hadi said.
The patterns of the prevailing wind direction have been the source of both the drought and the new surge of rain, he said.
Earlier in the year, there was a very strong ridge of high pressure (the Bermuda High) across the area. It created strong easterly winds, pushing thunderstorms to the west coast of Florida.
“However, within the last month we’ve seen a lot of rainfall on the east coast as well … so we’ve seen an improvement,” Hadi said.
Things changed when a trough settled over the eastern U.S., weakening the easterly Bermuda High winds, and allowing storms to soak the east coast.
“That’s really the main driver as to whether we’re going to have a drought on the east coast or the west coast (of Florida),” Hadi said.
In fact, the west coast has had below-average rainfall for the past 14 days, according to the South Florida Water Management District, while the east coast has had above average rainfall for this time of year.
A fringe benefit of the trough dominating over the east and the Bermuda High weakening has been less risk from hurricanes.
As the Bermuda High pulled away from the east coast, it allowed Tropical Storm Gabrielle and Hurricanes Humberto and Imelda to curve north, away from land.
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