We may be in autumn, but here is when to expect those cooler temps

RUSKIN, Fla. - Astronomically speaking, Autumn began at 11:09 PM Wednesday (September 22), but across West Central and Southwest Florida, the temperatures are anything but fall-like.

We continue to have high humidity with dew points in the upper 60s to lower 70s during the afternoon hours, along with high temperatures in the lower 90s.

So, when can we expect some significantly cooler temperatures? The National Weather Service in Ruskin gives us a pretty good answer.

They published several charts of low temperatures in various Florida cities. You can find the data at http://www.srh.noaa.gov/images/tbw/TopNews/PDF/WhenCool10.pdf

Looking at the tables, we find the average time of the first cool front appears to be during mid-October. Temperatures generally fall into the mid 50s across inland portions of the nature coast and below 60 degrees elsewhere across west central and southwest Florida. The only exception is near the coast, where the water keeps temperatures higher and these areas take longer to fall below 60 degrees, as seen in the chart for St. Petersburg.  That city usually gets below 60 degrees around October 27, while Tampa gets that cool around ten days earlier.

Another way to look at when it may cool down is to take a look at the graphs of the average (based on 1971-2000 Normals) and record low temperatures during the autumn at a few sites across the region.

From these graphs (see the graph for Tampa above), during some years the first cool down has occurred as early as mid-September. But looking at the average lows we see that for the most part it takes until November before low temperatures fall into the mid 50s north to lower 60s south on a consistent basis.

Take a look at the entire paper at the national Weather Service website. For those itching for more signs of autumn, they included a chart of Fall Foliage Peak Times across the US.

http://www.srh.noaa.gov/images/tbw/TopNews/PDF/WhenCool10.pdf