09 July 2020

Fay becomes earliest 6th named storm on record

A low pressure system that tracked over the southeast U.S. the past few days emerged over the ocean on Wednesday, and finally gained enough organization to get upgraded to Tropical Storm Fay.  Fay is the 6th named storm of the 2020 season; it formed 12 days before the previous record-holder (Franklin on July 21, 2005) and 8 *weeks* ahead of the average 6th named storm formation.

Of course, having a bunch of named storms is one thing, but it's important to keep them in perspective. So, far, the six of them have been around for a total of 10 days, and the strongest one topped out at about 58 mph (mid-range tropical storm).  This is nothing like 2005 which already had a Category 4 hurricane and a Category 5 hurricane was in the making on this date! 

Fay is centered just 40 miles off the North Carolina coast, and has peak sustained winds of 45 mph, though those are found offshore to the east of the center.  It is moving toward the north at 7 mph and that motion is expected to continue. That will bring it to landfall near NJ/NY on Friday afternoon.  As such, tropical storm warnings have been issued for coastal NJ, NY, and CT.

In terms of timing and planning, the graphic below shows the most likely arrival time of tropical storm force winds (lines), and the probability of a location receiving those winds (shading). Coastal areas can expect elevated tides and some flooding.

The rainfall outlook for the next couple of days is shown below:

Elsewhere in the basin, no activity is expected in the foreseeable future, but the next name on this year's list is Gonzalo.

06 July 2020

Edouard forms south of Newfoundland

Tropical Depression 5 formed on Saturday morning southwest of Bermuda, then tracked northeast.  It was upgraded to Tropical Storm Edouard on Sunday night when it was located in the open north Atlantic, south of Newfoundland. 

Edouard is the earliest fifth named storm on record in the Atlantic, beating Emily (2005) by six days. The similarities end there: Emily was a long-track hurricane in the Caribbean Sea and Gulf of Mexico that made landfall on Mexico twice, while Edouard is a brief messy tropical storm that won't affect land.

This storm has a very brief window to exist as a tropical cyclone... it is expected to transition to an extratropical cyclone on Monday night into Tuesday morning as it passes over much colder water temperatures and encounters strong vertical wind shear. Edouard is racing off to the northeast at nearly 40 mph!

Elsewhere in the basin, the National Hurricane Center is giving a 40% probability of a tropical cyclone developing off the coast of the Carolinas in a few days, and a 10% probability of a tropical wave developing in the deep tropics today. The model guidance has not been showing much hint of anything to be concerned about with the Carolinas system, but it's worth paying attention to. The next couple of names on this year's list are Fay and Gonzalo.

23 June 2020

Dolly forms south of Nova Scotia

The tropics have sparked back to life, sort of. Subtropical Depression 4 formed on Monday afternoon north of Bermuda. By Tuesday afternoon, it had consolidated and strengthened enough to get upgraded to Tropical Storm Dolly, the fourth named storm of the season. As of 5pm EDT on Tuesday, Dolly has peak sustained winds of 45 mph and is forecast to weaken as it heads northeast over cooler water. It has had the benefit of the warm Gulf Stream water up until now.

Zooming out of that first satellite image a bit, we see Dolly located south of Nova Scotia, and we also see the spectacular plume of Saharan dust that has been making its way across the tropical Atlantic for the past week or so. It now covers Puerto Rico, Hispaniola, Jamaica, and Cuba. It will reach south Florida on Wednesday. This is a very common thing to happen in June and July, but this plume happens to be more dusty/dense than most, so it's getting more attention than most.

We're already on the fourth named storm on June 23. Over the past 50 years, the average date of fourth named storm formation is AUGUST 21! Only two other years have had four named storms by this date: 2016 and 2012. Those years ended up with 143% and 133% of the activity in an average year, respectively (defined in terms of ACE, or Accumulated Cyclone Energy).

Once this big Saharan Air Layer outbreak settles down, the tropical Atlantic should become more conducive for activity (another 1-2 weeks?)... and the next two names on the list are Edouard and Fay.

P.S. If anyone wants an excursion, 2008's Dolly was a very interesting hurricane!