79ºF

The tropics stay quiet while South Florida sizzles

July 1, 2020, satellite image of the tropics.
July 1, 2020, satellite image of the tropics. (CIRA/NOAA)

There is no sign of anything developing in the tropics. The atmosphere is dry and dusty from one plume after the other of Saharan Dust. Over the next week, the dust is forecast to spread out over most of the Atlantic from the coast of Africa to Texas and around the Gulf Coast, including across Florida. 

NASA runs a specialized computer forecast model that predicts how the dust will disperse. It shows that the density of the plumes will decrease with time, but for the foreseeable future, more dust will feed into the pipeline. The image is for where the dust will be on July 4th.

As a result, no development is expected in the tropics through the weekend, and likely much longer. 

Weekend dust distribution across the tropics.
Weekend dust distribution across the tropics. (NASA)

We may see another one of those non-tropical-becoming-somewhat-tropical systems off the Southeast coast next week, however. The computer forecast models indicate that it could organize as it moves out to sea early to mid week.

A disturbance will drop down from the Upper Midwest over the next few days, rotating around the giant New England upper low. The upper-level low-pressure system that is forecast over the Southeast over the weekend will finally change the incessantly super-hot weather pattern over South Florida a bit. The change should begin late this week and continue into next week. A better chance of thunderstorms should stop the record-breaking streak of heat.

South Florida’s record heat

Yesterday, the weather pattern evolved into a classic one for South Florida heat. High pressure strengthened over the Gulf of Mexico, which tends to keep the ocean sea breeze from pushing very far inland. With strong June sun, few clouds and a light breeze blowing over the city on the way to the Miami airport thermometer, the temperature soared to 98, tying the highest ever recorded there.

The all-time record for Miami was set on July 21, 1942, but not at today’s Miami International.  At that time, the official readings were taken at Miami Municipal Airport, which was about six miles north on Le Jeune Road, across from Amelia Earhart Park in Hialeah. Ironically, less than two weeks after that record temperature was recorded, the official recording site was moved to the old Miami International Airport terminal on NW 36th Street, just west of Le Jeune Road. Since then, it’s been on the current airport property. 

The NOAA reanalysis of the weather pattern on the record-setting day in 1942 shows a wind flow similar to what we had yesterday and expect to have today and tomorrow. Whether we set another record is an open question because a random afternoon shower over the airport can make a big difference, along with other small factors. In any case, we’re going to be under an extremely hot weather pattern for at least the next couple of days.


About the Author: