Apr 27, 2015

Seasonal anatomy of drought

Drought in July?

Not in the Big Cypress Swamp.


The above chart shows the monthly distribution of moderate and severe drought in Big Cypress Nat'l Preserve as calculated from 1992 to present.  Moderate drought occurs in the four-month span from February through June. Severe drought only occurs in three months -- April, May and June. That leaves the other seven months -- July through January -- as being virtually drought free. Interestingly, June is our rainiest month but also a high drought month, too. The reason for that is that during deep drought years the severe draw down of the water table by late spring requires time to fill back up. Also factoring in are those years when the wet season is late to start or we have an especially dry May.    


The chart above proves it.

Summer rains by then are guaranteed to have filled up the shallow aquifer and flowed over into the surrounding low lying swamp.   But don't count drought in June out even though traditionally it is our rainiest month.


That's why I often call June soaking in season.

And that's why this year's drought season could still have a ways to go.

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