Dean intensifying, near Category 5 strength

Hurricane Dean is intensifying. The latest Hurricane Hunter data and satellite intensity estimates both show an intensifying storm, and the 3:54pm EDT eye report showed a 6 mb pressure drop in less than two hours, which is a big fall. The pressure now stands at 918 mb, which is the lowest pressure Dean has attained thus far. The storm is over waters with very high heat content, and is under light wind shear, so continued intensification is probable. Landfall is expected near Chetumal, Mexico, just after midnight local time. Dean will be a tremendously destructive storm for southern Mexico. Dean is powerful enough to be able to survive the crossing of the Yucatan as a hurricane, and hurricane advisories have been posted for cities on the western coast of the Yucatan Peninsula. The only hurricanes on record that survived crossing this portion of the Yucatan and maintaining hurricane intensity were Hurricane Roxanne of 1995, which hit just south of Cozumel as a Category 3, and emerged near Campeche as a Category 1; and Hurricane Janet of 1955, which hit near Chetumal as a Category 5 storm, then weakened to a Category 2 storm when it popped out into the Gulf of Mexico south of Campeche. We can expect Dean will carve out a path of great destruction all the way across the Yucatan Peninsula, then potentially re-intensify before hitting Mexico again along the Gulf Coast in the Bay of Campeche.

Jamaica and Haiti
News is still slow to emerge from Jamaica due to blocked roads and lack of electrical power. It does appear that the north coast, including Montego Bay, did not suffer extensive damage. News reports now indicate four people died on Haiti, and 150 homes were destroyed.


Figure 1. Current satellite image of Dean.

Links to follow today:
GOES rapid scan satellite loop
Radar from Cancun, Mexico.
Chetumal, Mexico observations.
Cozumel, Mexico observations.
Belize City observations.
Campeche, Mexico observations.
Morphed microwave animation.

Disturbance 92L needs to be watched
An area of disturbed weather associated with a tropical wave a few hundred miles northeast of the Lesser Antilles Islands, "Invest 92L", has changed little in organization today. Wind shear is about 5-10 knots in this region, and an upper-level anticyclone has formed over 92L. This is a very favorable environment for intensification, should 92L start to get organized. The disturbance has the potential to develop into a tropical depression by Wednesday. It is moving west to west-northwest at 15-20 mph, and will be near the central Bahamas by Wednesday, and the east coast of Florida by Friday. It does not appear that any troughs strong enough to recurve 92L will swing by until Saturday at the earliest.

Tropical wave approaching the Lesser Antilles
A tropical wave approaching the southern and central Lesser Antilles islands will bring showers and gusty winds to the islands Tuesday. Wind shear has dropped to 5-10 knots over the wave, and there is some potential for it to develop as it moves west to west-northwest into the Caribbean Sea.

I'll have a full update Tuesday morning at about 10am EDT.

Jeff Masters