Welcome to Summer

Where Go Hydrology contemplates its longest season

dry season

Summer sputters to end
Who keeps turning on and off the switch?

It’s a long summer in south Florida …

And then suddenly like a flip of a switch the rains stop.

The regular pattern of afternoon rains stops in early October

At least that’s how it seemed a week ago.

The late September slug of air had us convinced the summer rain machine had shut down for the year. Ten days later more humid air has returned, and the rain machine has even shown some signs of life. But the bigger picture is it’s starting to sputter off. Usually by Columbus Day (early-mid October), the winter dry season has begun even if from a monthly book-keeping sense we wait until November 1st to start the official dry season clock.


Change in the air?
Not scarf weather, but definitely fall-ish

Although not an official cold front …

And it’s still possible to overheat in the midday sun:

The cooler morning and evening temperatures are a welcome relief. Daytime highs and still ramping up into the high 80s and nighttime lows are staying above 70, but with daylight hours on the wane and last week’s dose of a drier air front, its as cool an early October as I can remember.

Fall is definitely in the air.

Did summer just end?
Just when it was getting interesting

It was shaping up to be a subpar summer …

And then September kicked into high gear.

The swamp finally peaks, but for how long?

Back to back weeks pushed the swamp to its annual peak.

Then came the recent front of dry air?

Overnight the rain machine shut down.

Or is there still time for it to rev back up?

A flooded marl prairie with periphyton

I‘m never one to complain about the start of fall, but seriously – summer was finally starting to get interesting. It’s good to see the swamp’s sheet of water spreading out.

big weather

Steaming swamp
Think hot asphalt after a cool rain

From the distance it looked like smoke …

Or maybe dust kicked up from the limerock road.

It looked primordial, but it was actually super chilled

Only upon closer inspection did we see it was steam.

The source?

Similar to a hot asphalt road steaming after getting cooled down by an afternoon shower, the wisps of water vapor hovering over the cypress stand were the result of an ice-cold drenching from a super thunder cell.

The super cell, looking north, about 15 mile east of the strand

As good fortune would have it, I actually took a photo of the thunderstorm about an hour before and 15 miles upwind from the steaming strand. The air among the wisps was incredibly cooled and the fragrance from the cypress intense. Landing and walking in the water was further proof.

The water was chilled as if it had hailed.

hydrologic holidays

Florida Groundhog Day
Does the groundhog's shadow portend early fall?

South Florida doesn’t have a winter, therefore by definition it can’t have a Groundhog Day?

Or is it just hiding in plain sight instead?

Groundhog and cloud
Is that a cloud,
or a Giant Groundhog?

Groundhog Day on the continent is a celebration that celestial winter is half way done. By contrast in south Florida we are content to never let winter never end.

Our summer on the other hand is another story.

What continental transplant (me included) hasn’t at some point during Florida’s unending summer craved a little dose of fall air, especially come Labor Day when friends and relatives from “up state” and “off peninsula” are just beginning to rejoice in the first of many rounds of crisp autumnal air. Meanwhile down on the south peninsula we are left to sweat out another six weeks of Old Man Summer. It usually isn’t until Mid October that finally (and at long last) a cold front blasts through.

In my mind that’s what makes Labor Day South Florida’s Groundhog Day equivalent.

Will Summer end soon? Answer: See above

Only south Florida’s groundhog doesn’t emerge from ground to look for his shadow: It appears as giant cloud (see photo above) …

Casting a shadow on us instead.

Summer love affair
Why Floridians ❤ Summer

Summer in Florida gets a bum rap.

Too hot, too humid, too many mosquitoes.

Comparison of air temperatures up the East Coast

And I’m not here to argue that it isn’t inordinately long compared to what anybody is used to up North.

Look at that beauty!

But I will put a plug in for Florida’s summer clouds.

They are by far the best of anyplace I’ve ever been.

Find out more in this podcast why summer is actually Florida’s seasonal gem.


Warm winter days
But save the sweater for summer!

It’s easy to confuse winter …

For summer in south Florida.

Chart showing winter warmth in Naples FLA, 1970 – present

The reason?

Around half the winter rises up to or above 80° F. That qualifies as summer-like weather if you’re from Up North.

This winter only about 40 percent of the days rose above 80° F, markedly down from the previous five winters. But look at the three-year run of cool winters from 2008 to 2010 when only a quarter of the winter days in Naples broke the 80 degree plane. Or the scorching hot winters of the early 70s when the winter mercury mark topped 80 three times as much.

My point?

In south Florida we often mistaken winter for summer, but rarely do we get it confused the other way around. (That doesn’t mean you don’t need a sweater in the summer when the air conditioning is too low!)

70 degree rule

People winter in Florida, as in the verb.

We call them snow birds.

Naples enjoys 3 weeks of winter to 20 weeks of summer

To them, without a doubt …

Winter the noun does not exist in south Florida.

But for us “year rounders” the thermometer couldn’t be more clear. We go by the 70 degree rule. What is the 70 degree rule? Any day that doesn’t rise above 70° F is winter and any night that doesn’t drop below 70° F is summer. That gives us on average 18 days of winter and 130 days of summer. As for the rest of the days, us “year rounders” call those spring and fall; or in the parlance of the northerners, “– that’s ridiculous, it’s all summer!”

Summer – clouds = Very hot!

Humidity and shade …

Usually help stifle back Florida’s high noon sun.

We’re now in the summer plateau:
Daytime highs and lows nineties and
nighttime lows in the high seventies
for the next 3-4 months

Not this week!

A run of mostly cloud-free days allowed the heat to build up and persist.

To make matters worse, Labor Day is still two months away.

Not that Labor Day even matters.

Comparison of Naples
to other places along
the East Coast

Summer’s grip in south Florida won’t relent until mid October.

Suffice it to say, the summer slog is upon us.

Our only hope is for the clouds and rains to return soon!