Appearances (versus reality)

Considering it wasn’t much of a wet season …

In terms of filling up the swamp.

Pop up shows may appear,
impressive, but don’t deliver
much rain

The skies of recent sure have the look

Of the scenic summer rainy season in full gear.

But don’t be deceived:

The meteorological dry season has begun.

The only thing that can save us now (i.e. in terms of keeping the water table up) is a good couple dousings from a continental-delivered northern front.

Most dangerous swamp

Of the many things people fear

In the swamp …

Is there any more peaceful
a spot than a visitor center
of a national swamp?

And we can run down the list:

Alligators, pythons, panthers, dehydration, getting stranded, mosquitoes, hurricanes and extreme heat (and I could keep going).

Just be careful (and slow down)
when turning in!

Driving (fast) is the most treacherous by far.

Just ask any number of gators or wading birds who have been struck

Or this guard rail (above) if it could talk.

Moral of the story: Please slow down!

“Hill country” mirage

I still remember the first time I flew over the swamp.

“Wow,” I said.  “Look at all those hills!”

Don’t be deceived,
the swamp is actually
quite flat

Soon enough I learned they were actually holes, i.e. depressions, that mimic the look of hills by way of the parabolic shape of the trees that grow within.

Cypress domes and strands are the swamp’s deepest spots.

Can you see the dry season refugia
pool in the center of the dome?

And in spring, the only spots you’ll still find your last refuges of water.

Mixed signals

I remember this cloud well:

It seemed a clear sign the summer rains were about to begin.

Calm before the fire
April 29th 2011

Instead it brought lightning and put the swamp ablaze.

It was the year of our drought of record and the Jarhead Fire.

Moral of story: Never trust a cloud!

Summer drought of the big rains?

Where have all the Big Rain Days (BRDs) gone?

We’ve only had two so far this year (we average six per year) … and have yet to have one since the start of the wet season in May.

Florida has a hyperactive water cycle:
Rains are as big as the sun, i.e., evaporation, is intense.

What exactly is a Big Rain Day?

The calendar graph below shows a full history of south Florida’s Big Rain Days from 1992 to present. BRDs are shown on the chart as the blue dots. The larger the dot the bigger the BRD. Among the biggest were Fay in August 2008 and Mitch in November 1998. But even the smaller blue dots are regionally significant days of rain.

BRDs are formally defined in Webster’s Dictionary* as any day in which 1 inch or more of rain was recorded across all of south Florida. It’s one thing to record multiple inches of rain at a single gage, or a cluster of gages in one basin, but it takes the arrival of a huge weather system to spread a full inch (or more) of rain across all of south Florida from the Kissimmee headwaters on down.

These are overnight hydrologic game changers.

This could be one of the few wet seasons
that misses out on at Big Rain Day:


Do you see the other?

When do Big Rain Days occur?

The natural assumption would be the summer wet season, and to a point that is correct. Over the past two decades, sixty percent of the Big Rain Days have fallen in the wet season months of May through October. Surprisingly, July – smack dab in the middle of our rainy period – is the single most least frequent month. The biggest month is June: It accounts for one of every five BRDs.

Also big are September and October –

Combined, they account for one of every four BRD.

Continental fronts, not tropical weather, bring us our dry season BRDs.

So I wouldn’t count this year out just yet.

And by the way, I just double checked:

Big Rain Days are not included in Webster’s Dictionary just yet, nor in any of my meteorology text books, although – for the record – I think it definitely should be. The term was coined by meteorologists with the South Florida Water Management District in West Palm Beach.