When is fall in South Florida?

I mean, really! The leaves of our tropical and subtropical trees aren’t really deciduous, so we can’t rely on the glorious fall defoliation as an indicator. This defoliation, which some people like because it’s preceded by a change in color from healthy chlorophyll green to less healthy oranges, browns, and reds, is caused by hormonal changes in the tree which are in turn triggered by shortened day length and cooler weather. These hormonal changes lead the trees to sever the links between their twigs and their leaves; if you look at the leaf stem, you’ll see the typical abscission marks that indicate that the autumn leaf wasn’t ripped from the tree by the force of the wind; it’s more like the tree was pushing the leaf off, and the wind just encouraged it to meet its fate…

No, we here in Florida don’t have this visual cue.

What we have, as you can see in this post from the South Florida Watershed Journal (one of my favorite Florida blogs), is a temperature boundary. Robert V. Sobczak has a fabulous graphic that shows how the 60-degree line advances slowly across the state from north to south. By this definition, fall won’t hit Boca for a few weeks!

We did get an early precursor of its arrival in the middle of October, but we certainly didn’t get the “typical” fall arrival that I predicted (because, you see, I based my prediction on my memory rather than the data). I always tell people that I never thought I’d wind up in Florida, but now that I’m here, I don’t want to be anywhere else between Halloween and Easter. Well, make that Thanksgiving and Easter, now! Fall starts late down here!

This week the weather has begun to moderate somewhat; we’re finally coming down from the record heat (daytime highs from the high 80s to low 90s in November!) to “normal” temperatures, but, as that graphic shows, we have a ways to go before we feel the full blast of fall. Brrr. 60s!