ORLANDO, Fla. – The cold is coming. I will add, unusual cold for Florida’s taste.
I’ve started to notice a few questions being asked on social media as well, regarding whether this is “normal” for the southeast so early into fall.
It’s now officially sweater weather season for a lot of us, especially when you factor in how much cooler a bulk of the U.S. has been compared to what we experienced during the summer.
One other season has yet to wrap, despite having likely fallen to the back of our minds in recent days. Hurricane season is still cranking out there. While the Atlantic is pretty quiet, and some could say the hurricane season for us ended with the departure of Hurricane Melissa, there’s another part of the world still producing those tropical systems we track constantly from June to the end of our November.
In the west Pacific Ocean, there are two typhoons active in their tropical basin. One is now quickly turning into remnant showers and storms as it rolls further inland, and the other is preparing to intensify.
When hurricanes, cyclones or typhoons get strong, they produce their own upper level winds.
Keep in mind each of the different names I listed above are talking about the exact same type of storm: hurricane is the title used for the east Pacific and our Atlantic basin. Typhoon is what they’re called out west, and cyclone is their title if they pop up in the Indian Ocean, or South of the equator!
As they rapidly intensify into powerful tropical features, just as Melissa did the end of October, the upper level exhaust that comes out of the storms center begins to modify their local environment.
The local environment in its simplest definition is whatever happens to be near the hurricane as it starts to strengthen or hits the rapid intensification phase.
The exhaust that comes out of the core of a hurricane, described as “outflow” can be just as powerful as the jet stream that drives our cold and warm fronts over the U.S.
Now combine that racing outflow from the center of a storm with an approaching extension of our jet stream and things can get a little wonky.
Remember last year in October when Hurricane Milton roared through our state? Within a day or two, if not immediately following the storm, we were left with clear skies and cold temperatures? The first cold temperatures, mind you, we’d seen since the departure of winter and spring at the start of the calendar year.
That’s because Milton pushed east along the leading edge of a trough and leftover cold boundary draped from Texas back across Georgia and northern Florida.
Look closely at the satellite image of Milton above. See how behind the hurricane there’s almost no clouds whatsoever? That is the front and dry air being tugged down in hot pursuit of our hurricane.
This same front is what helped knock Milton down a few notches, otherwise we’d have likely received the Category 5 version that spawned in the Bay of Campeche.
As the outflow from a tropical cyclone feeds into our jet stream winds, they tend to “couple.” This can create some enhancements in the wind flow, creating stronger ridges and stronger troughs. Ridges are associated with warmer conditions, and troughs drive colder air south from up north.
Hurricane Melissa was a pre-cursor to where we are now. A cut-off piece of energy was wandering across the Gulf Coast states into Florida just in time to catch Melissa and keep it far away from us. At the same time, Melissa having powered up to such a historic Category 5storm helped feed the flow that was coming down over the eastern U.S.
Now, we also have typhoons doing the same thing in the West Pacific. That energy has to go somewhere, and it moves west to east on the same conveyor from that corner of the world, into ours, and back again.
So while this is unusually cold for Floridians, and we don’t typically see a snap this robust in early November, I promise it isn’t anything bizarre happening with the weather.
The rest of the month could actually be unseasonably WARM once all these tropical shenanigans really settle down and La Nina in the tropical Pacific can do its thing.