To be notified of news about this storm and others through the season:

For computer model forecasts, visit our charts page.

Dean Preparing to Strengthen Significantly (UPDATE: NOW CATEGORY THREE)
August 17, 2007 - 4:28 PM UTC (subtract 4 hours for EDT)

UPDATE 2:01PM EDT: The latest advisory from the National Hurricane Center updates Hurricane Dean to Category THREE with winds of 125 mph and notes a continued pressure drop to 961 mb. Additionally, Dean is looking much stronger and has a better defined eye as can be seen in the below images. I expect he will shape up and begin to look more his strength soon with a well-defined eye and gain nicer outflow.


Visible Satellite

Water Vapor Satellite

Hurricane Dean had been stalling his intensification for almost 24 hours, hovering between 970mb and 979mb of central pressure but has now broken away from the dry air that was inhibiting his growth. The latest USAF Hurricane Hunter to fly through Dean noted central pressure of 964mb and an increased wind speed to 105mph making Hurricane Dean a Category 2 Hurricane.

We haven't been able to see much of an eye in quite a while, but NHC is reporting a closed eyewall and you can just barely see it in this satellite image. Dean is looking slightly more ragged than he did about an two hours ago (1315z vs 1515z) but is still looking much more healthy than he did yesterday at this time. Moving into the warmer Caribbean waters with less dry air around him have done promising things for further intensification as the models have been indicating for several days.

IR Satellite
The latest model runs continue to show astounding congruity between the models, tracking Dean almost on top of each other WNW directly over Jamaica until just south of the Caymans where they begin to diverge with some models bringing Dean over the Yucatan and some bringing him in a more Wilma/Ivan track between Cuba and the Yucatan and into the central Gulf of Mexico. Our ability to predict beyond 3 days (beyond just past Jamaica) is very suspect though, as there are many variables that we just cannot control. All interests in the Gulf of Mexico from Texas to Florida should keep a close watch on Hurricane Dean.

If, as currently indicated, Dean tracks directly over Jamaica, we will have to reevaluate everything. Jamaica has quite large mountains in the center of the island and Hurricanes do very poorly when passing over high elevations. Jamaica could do quite a number on our storm and knock his strength down significantly with the right conditions.


Tracking Models

The intensity models (which are notoriously inaccurate) are almost uniformly calling for extreme intensification into a Major hurricane, possibly a category 4, but are slightly less aggressive than earlier today and yesterday. It is important to note that intensity forecasting is not very well understood and we can only look at what data we have to make a judgement.

Tropical Storm Warnings and Hurricane Watches are up for most of Hispaniola, Puerto Rico and much of the eastern Caribbean, but look for those easternmost warnings to be dropped soon as Dean continues his trek westward at the speedy clip of 21mph.


NHC 5-Day Cone

As always, you can get the latest model runs from the Dean Charts Page or our general Charts Page and keep checking TheStormTrack.com or subscribe to our RSS feed or Twitter feed for the latest Dean updates.


Posted by Jordan Golson | Permalink