I know what you’re thinking: What happened to fall and spring. It’s a sad story in Florida, but they actually got lost. They somehow slipped away in a tide and, although we’re not a hundred percent sure, we think they are swirling around in a gyre in the mid Atlantic or possibly even washed up on the European shoreline, possibly in Belgium or France.
Joking aside, Florida also has its four celestial seasons. It’s just meteorologically we split the year in two: a six-month wet season from May to October and a six-month dry season from November to April. During the wet season, it rains almost every day, and usually in the form of afternoon thunderstorms. During the dry season, it still rains, but only periodically. Most days are sunny and cloudless, or less clouds. Technically, if you want to split water drops, the wet season doesn’t crank up to high gear until the later part of May and with the exception of tropical events, usually shuts down in early October. But for bookkeeping purposes, we lump May and October into the wet season.
Diagram depicting end of the wet season
Now here’s the tricky part: The term “wet” refers to the regular rains falling from the sky, not the sogginess factor of the water on the ground. Out in the Everglades and Big Cypress Swamp, the ground remains flooded with water for weeks (even months) after the “wet season” has ended.
For me, the term summer “rainy” season — not wet season — is a more accurate description of the season. However, climactically speaking, the term “wet and dry season” climate is the norm. So who am I to argue with the text books?
Final note: The Big Cypress Swamp on average receives around 42 inches of its 53 inch annual rainfall total during the 6-month wet season, or about 80 percent.
Usually means the end of the season that came before.
History of drought in Big Cypress Nat’l Preserve
Well, hold your horses. While Memorial Day Weekend does mark the unofficial start of south Florida’s summer wet season, and to be sure from this point on we can expect the regular build up of afternoon clouds and thunderstorms — it may take a few couple weeks before the swamp starts filling up, or it could happen in a day. Until that time and until that day, the swamp is still in a state of drought. Not as deep as last year. But as you can see on the hydrograph above, it wasn’t until early June that the water table bottomed out. June is soaking in and filling up month. What we do know is that probably by July and definitely by August the swamp will get its water back.
The start of fall is easy to see in the swamp: Look no farther than the needles of the cypress trees turning brown then falling off. But does the swamp have a similar botanical clue that signals the start of the summer wet season?
Why? Up on the continent, the end of summer and Labor Day go hand in hand. Not that you need go immediately from a swim suit to wearing a scarf from one day to the next, but its pretty close — if not like clockwork. Labor Day definitely favors on the summer side of the divide, serving as its de facto “last hurrah.” Then there’s the case of Memorial Day down in south Florida. Just as Labor Day may usher in a freshet of cooler and crisper air Up North, Memorial Day typically is the tropical (not polar) opposite: greeting south Floridians with a chinook of humid air at their door, suddenly giving urgency to the old expression — “Close the door you’re letting the air out!” — and leaving one to wonder if per chance he or she didn’t mistakenly put on a heavy down sweater instead of a T-Shirt. Yes, it’s that warm and humid. There’s another saying in Florida: “It’s not the heat, it’s the humidity.” Between Memorial Day and a solid six weeks after Labor Day, the expression especially applies.
Summer rainfall in south Florida (inches) replacing months with major holidays as the major color-coded intervals
But maybe a better way to frame it is by major holidays. The reason? For one, the rains that come “just before” and “just after” the official wet season (i.e. as defined from June through October) are just as important as the summer rain itself. Timely spring rains can boost the water table just before the summer rain machine turns on in the same way that November Soakers can prolong the summer high water stand. Look no further than last year’s Eta (in November) as proof. I’m not saying to do away with months (yet), but I do believe holidays for nice mile markers for refining our Water Cycle IQ. BTW: The above chart is for south-Florida wide.
Can you guess which basin reliably gets the least amount of rain from May to October? a. Big Cypress Swamp b. Southwest Coast c. Miami-Dade d. Lake Okeechobee e. Water Conservation Area 3 f. a and c only
We cover them all: The Districts, the estuaries, the aquifers and the watersheds. Also the rain, and the dew. Plus the humidity. Did I mention evaporation? The list goes on.
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