Florida Will Participate In Autumn If It’s The Last Thing The Other 47 States Do, So Help Us

Florida will soon learn that the terms of autumn are non-negotiable. The Sunshine State will participate in chilly fall mornings even if it’s the last thing the other 47 contiguous states do, so help us. (Alaska can send moose if they want. Hawaii can sit this one out.)

When the state isn’t exporting weird headlines or conducting horrendously-flawed elections, residents spend much of the year looking for ways to keep cool. It’s no surprise that it stays toasty pretty late into the year in Florida. The state is a huge attraction during the winter months because its enduring warmth seems unshakable outside of the biggest, meanest storms that envelop the eastern half of the country.

The heat of late really has been unshakable. Not only has it been unusually warm so far this fall even by Florida standards, but the months-long extension of summer has approached record territory across the peninsular portion of the state.

The period between September 1 and November 14 saw the warmest average daily temperature ever recorded at Miami International Airport. The average of all the daily average temperatures—that is, the high and low temperature averaged together each day, and all those averages then averaged together for the entire 76-day period—came in at 81.8°F, which is the warmest recorded during climatological fall since records at the airport began in 1937.

Here’s a breakdown of temperatures in Miami so far this fall:

You can see that daily highs have been above-average, but they only deviated from normal by a degree or two each day. The difference is in the lows. Most days saw a low temperature dramatically higher than what you’d expect to see for this time of the year. Except for the a couple of days at the end of October, the low temperature in Miami has remained in the mid- to upper-70s almost every day since the end of summer.

Hot and humid days fading into warm and humid nights provides residents no respite from the heat. Warming nighttime temperatures is a noticeable trend across much of the United States. The increase in the number of warm nights is one of the concerning effects of climate change.

Making matters worse is that it’s a wet heat. The Iowa Environmental Mesonet shows that Miami has seen dew points of 76°F or warmer for nearly 1,700 hours so far in 2018, an excessively-muggy length of time that’s second only to 2005. Dew points are generally considered to be oppressively humid once the value rises above 75°F.

I’ve focused on Miami in this post because it’s an extreme example of summerlike heat and humidity lasting well beyond its expiration date, but it’s not just Miami that’s suffering. The average daily temperature since September 1 is also sitting in record territory up at the major airports in Orlando and Tampa. It remains to be seen how much averages for the entire fall will moderate back toward normal with the upcoming cooldown.

Thankfully, things are going to change soon, even if it’s only by a little bit. Look at this GFS model animation of dew points over the next couple of days:

Source: Tropical Tidbits

Ahhhh. That’s nice. Air temperatures are likely going to remain warm for the next couple of weeks—hovering at or slightly above average most days—but the break in oppressive humidity will make it feel nicer and the relatively drier air will allow nighttime temperatures to finally fall back near normal for this time of year.

Communities near Pensacola will likely see a hard freeze on Thursday morning, and morning lows on Friday could dip into the 30s across inland areas as far south as Ocala. Low temperatures in the 40s may even reach the northern shores of Lake Okeechobee on Friday and Saturday.

---