The chart above shows plenty of warm surface water to support tropical development in the Gulf, only a small pool of slightly below normal temperatures. Surface water temps are now 84-89F, most of my college textbooks put the formation requirement at 82/83F with 80 the bare minimum.
Other tropical systems like this one have developed as a result of upper level (jet stream or slightly lower) energy (vorticity) dropping from land over the Continental U.S. into the Gulf of Mexico such as Alicia in 1983, Bertha 2002 and Edouard 2008. Bonnie in 1986 and the surprise no-name of 1943 may also qualify.
One benefit of this is that without it we’d be developing a scorcher of a heat wave again, instead it will be worse in the Western and Northern U.S. this week and next week:
Of course the price to pay will be muggy tropical air and some tropical downpours and more clouds.
Here’s an overview of where this has come from and the overall synoptic setting starting July 5th courtesy WeatherSouth:
THUNDERSTORM CLUSTERS AND VORTICITY ALOFT:
FORECAST 500MB JET STREAM PATTERN SETTING:
PROJECTED 850mb HEIGHTS AND VORTICITY 8PM WEDNESDAY:
Whether or not it gets a name and regardless of ultimate intensity ALL areas along and near the Gulf Coast should prepare of days of periodic heavy rain, thunderstorms and flooding.
By Friday a FRONT sinks down from the North and will help “tap into” all the tropical moisture as it stalls across the Southern states through the weekend and into next week:
Thus the tropical system will give an assist or boost to our humidity values enhancing cloud cover and providing isolated heavy downpours at times as we roll through the next 7 days (Above).
By the way, tropical cyclone/tropical low/tropical depression are all the same thing. All tropical storms and hurricanes are tropical cyclones but NOT all tropical cyclones are depressions tropical storms or hurricanes. (because tropical cyclone is a generic term).
Keep in mind that while track forecasts are quite accurate, forecast accuracy for intensity of tropical systems is poor.
With regard to intensity of this system something to note is where it finally develops a closed system. The sooner that happens and the farther South it happens increases the chance it has sufficient time over the bathtub temperatures of the Gulf waters to intensify more, so the farther South and a longer track West would increase odds it reaches hurricane strength (European model and some others).
On the other hand, a formation farther North means less space and time over water for much intensification and a weaker system (American GFS model).
Expect model and track forecasts to continue to wobble in all directions as subtle differences in the systems energy and the jet stream (location strength and timing of high and low pressure ridges and troughs) across the Northern U.S. will exert influence on the Gulf system within the margin of error.
I don’t pay too much heed to our “spaghetti plots” until we have an actual entity over water, but FYI:
Many models suggest at least the POTENTIAL for rapid intensification to at least NEAR hurricane force but uncertain as to when, how much and where.
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