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"The Joker" transforms intoTropical Storm Fay

By: Dr. Jeff Masters, 9:29 PM GMT on August 15, 2008

The true nature of the storm I've been calling "The Joker" has been exposed--"the Joker" is really Tropical Storm Fay, the sixth named storm of this busy 2008 Atlantic hurricane season. Fay moved ashore over the eastern Dominican Republic early this afternoon, after pounding Puerto Rico with heavy rains and high winds. I got this report from wunderground member isla2, who lives on the island of Vieques, just off the east coast of Puerto Rico:

I live on Vieques. I just wanted you to know that where I live mid-island (Monte Santo) we got NAILED last night by invest Fay. I cannot imagine it was not a named storm! I have been through a Cat #1 and this was just as bad. It seemed like around 10pm the constant lightning, thunder, sideways rain and strong winds began in earnest and hammered us till around 3 am. {My three dogs were glad to be inside - two vying to be closest to my bed and one hiding under the draped dining room table.} I was very glad I had put up our hurricane shutters!

I suspect that we were hit harder than the radar showed. If anyone had been here they would know that this was no mere Invest!!


Fay may not technically have been a tropical storm earlier today, but this trick of not having a closed surface circulation hid the fact that this storm had the same winds and rain as a tropical storm. Two Hurricane Hunter aircraft found sustained surface winds of 40-50 mph both north and south of the center of Fay this afternoon. Satellite intensity estimates at 2 pm today put Fay at tropical storm strength (40 mph). Despite the fact the center is over land, visible satellite loops show a well-organized system with a steadily increasing area of heavy thunderstorms. Upper-level outflow is fair on three sides, and spiral banding at the low levels is increasing. San Juan, PR radar shows the storm's rains have ended over Puerto Rico, but are hammering the eastern Dominican Republic.


Figure 1. Total estimated rainfall from Fay.

Links to follow
Wundermap for Hispaniola
Punta Cana, Dominican Republic radar

The forecast for Fay
Wind shear is a low 10 knots over Fay, and is expected to remain below 10 knots for the remainder of Fay's life. An upper-level anticyclone has set up on top of Fay, allowing the air lifted from the surface by the storm's heavy thunderstorms to be efficiently spewed out to the sides, ventilating the storm and promoting even more intense thunderstorm activity. This favorable upper-level wind environment is expected to last at least through Sunday.

The latest (8 am EDT) model runs have shifted the track for Fay considerably further west, maximizing the time Fay will spend over land. Fay will be passing over the high mountains of both Hispaniola and Cuba, which may force sudden jumps in the center position as the storm reforms closer to its heaviest thunderstorm activity. As a result, the track forecast for Fay has an unusually high level of uncertainty. "The Joker" will continue to keep us guessing!

If Fay does hit South Florida, the storm is likely to be a tropical storm or Category 1 hurricane, since it will not have enough time over water to reorganize much. I think the models are overdoing the intensification of Fay once it does pop off the coast of Cuba. We saw in 2006 that Ernesto popped off the coast of Cuba as a weak tropical storm, and took a full 36 hours to get its act together. If Fay misses South Florida and veers either to the east or west of the Peninsula, the storm could easily reach Category 2 status before a potential landfall either on the Gulf Coast or in North Carolina/South Carolina.

I'll have an update Saturday by noon EDT.

Jeff Masters

The views of the author are his/her own and do not necessarily represent the position of The Weather Company or its parent, IBM.