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Tropical Tracker: Hurricane Delta to make history

Storm will become 10th named storm to make landfall in United States

This Wednesday, Oct. 7, 2020 satellite image made available by National Oceanic and Atmospheric Administration shows Hurricane Delta in the Gulf of Mexico at 10:41 a.m. EDT. Delta made landfall Wednesday just south of the Mexican resort of Cancun as an extremely dangerous Category 2 storm. (NOAA via AP)
This Wednesday, Oct. 7, 2020 satellite image made available by National Oceanic and Atmospheric Administration shows Hurricane Delta in the Gulf of Mexico at 10:41 a.m. EDT. Delta made landfall Wednesday just south of the Mexican resort of Cancun as an extremely dangerous Category 2 storm. (NOAA via AP)

ORLANDO, Fla. – Once a storm enters the Gulf of Mexico, it more often than not impacts land.

The Gulf Coast has been battered by the 2020 hurricane season and, unfortunately, that looks to continue in the coming days.

The current forecast has the same areas that were devastated by Hurricane Laura in late August receiving another strike from Delta, a strong hurricane, on Friday.

Delta is forecast to impact some of the same areas Laura devastated just weeks ago.
Delta is forecast to impact some of the same areas Laura devastated just weeks ago.

Delta rapidly intensified in the Western Caribbean going from a tropical depression to a Category 4 hurricane in just 30 hours. Wind shear helped to "weaken' the small but intense core of Delta prior to making landfall as a Category 2 storm in the Yucatan Peninsula early Wednesday morning.

Delta’s rapid intensification

This is the part of the basin where rapid intensification really tends to occur.

You may recall Wilma in 2005 underwent ultra rapid intensification in this part of the Caribbean. Wilma still holds the record for fastest intensification for a storm in the Atlantic.

Wilma holds the record for fastest intensification in a 24 hour period in the Atlantic.
Wilma holds the record for fastest intensification in a 24 hour period in the Atlantic.

In a 24-hour period, Wilma’s wind speed increased a whopping 105 mph, from a tropical storm to a monster Category 5 hurricane.

Wilma holds the record for fastest intensification in a 24 hour period in the Atlantic.
Wilma holds the record for fastest intensification in a 24 hour period in the Atlantic.

Not only is there extremely warm water in the Caribbean, it is also very deep. Where a lot of times cooler water is churned up and that upwelling of cooler waters sometimes caps the strengthening, in this scenario, warmer water is pulled up, leading to a never-ending fuel supply while the storm is in that area.

The warmth and depth of that warmth is measured by the tropical cyclone heat potential. We talked a lot about this in the last Tropical Tracker of September.

Darker red equals more fuel, higher heat potential. Blue represents less fuel, low heat potential.
Darker red equals more fuel, higher heat potential. Blue represents less fuel, low heat potential.

The darker red indicates where there is an abundant amount fuel for tropical systems. This is exactly what Delta used to gain so much strength so fast. The blue color represents where there is cooler water and less fuel present. This will impact Delta on approach to the North Gulf Coast. More on that to come.

In addition to the extremely warm waters of the Caribbean there was also an area of high pressure basically sitting on top of Delta. This helped keep wind shear low and aided in Delta’s breathing, which assisted in Delta’s intensification.

Another Louisiana strike?

High pressure over Florida is steering Delta north and west. That area of high pressure is also helping to keep Delta away from the Sunshine State.

High pressure is protecting Florida from Delta.
High pressure is protecting Florida from Delta.

Laura rapidly intensified right up until landfall, but it is unlikely that Delta will do the same. Delta currently is over warmer water, not nearly as warm as the Caribbean, but will be moving over water that is in the 70s closer to the coast.

Water temperature in the Gulf of Mexico with the current forecast of Hurricane Delta.
Water temperature in the Gulf of Mexico with the current forecast of Hurricane Delta.

The cold front that supplied the fall feel to Florida last week is responsible for cooling down the Northern Gulf. This region now has below normal sea surface temperatures.

The water is below normal in the northern Gulf of Mexico
The water is below normal in the northern Gulf of Mexico

Typically, tropical systems like the water temperature 80 degrees or above. Delta will also encounter increased wind shear during its last few hours over water.

Conditions are favorable for intensification through Thursday , but become less favorable closer to landfall.
Conditions are favorable for intensification through Thursday , but become less favorable closer to landfall.

With that said, Delta could still strike the North Gulf Coast as a category 2 or 3 hurricane. The storm will also be growing in size, which will enhance the impacts.

Rewriting the history books

Delta will become the 10th named storm to make landfall in the U.S., breaking the current record of nine. Three of those storms, Isaias, Laura and Sally have caused at least 1$ billion in damage.

Nine named storms have made landfall in the U.S. in 2020.
Nine named storms have made landfall in the U.S. in 2020.

Meanwhile, 2005 currently holds the record for most named storms, when we reached Zeta.

2020 names
2020 names

In intensity, however, we aren’t close to records but are much above average.

The current accumulated cyclone energy, the measurement of intensity and longevity of an individual storm and season currently sits at 116.4. The average is 87.7. The hyperactive 2005 season generated an ACE of 245.3.

Of course, hurricane season doesn’t end until Nov. 30. Let’s hope we don’t add any more to that number.


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