Dry air impairing Gustav's development

[phantom power]

Jamaica is feeling the full force of Tropical Storm Gustav, as torrential rains and near-hurricane force winds pound the island. At 1:55 pm EDT, the Hurricane Hunters found the eye of Gustav on the eastern tip of Jamaica. Gustav's central pressure had dropped another 2 mb, to 983 mb, and the surface winds were at 70 mph, just below hurricane strength. Kingston, Jamaica recently reported sustained winds of 35 mph, and the pressure falling, at 995 mb.

It's a surprise the Gustav is here at all, because the atmosphere pulled a major trick out of The Joker's book last night. The ridge of high pressure that was forcing Gustav to the west shifted positions to be oriented southwest-to-northeast. This pushed Gustav to the southwest, and pumped in some dry air into the northwest side of Gustav. As a result of this dry air, and the weakening of the circulation due to interaction with Haiti's mountains, Gustav was forced to form a new center under heavy thunderstorms on its south side, away from Haiti and the dry air. As a result, Gustav is now pounding Jamaica. The ridge that forced Gustav southwest has now re-oriented itself, and is pushing Gustav due west again. Rainfall will be the main threat from Gustav in Jamaica, as it was when the storm hit Hispaniola. Gustav's torrential rains accumulated to over 12 inches in southern Hispaniola, triggering floods and landslides that killed 22 people. It appears now that eastern Cuba will not get much rain from Gustav.

Visible satellite loops show that Gustav has already suffered from its impact on Jamaica. A large Central Dense Overcast (CDO) of high cirrus clouds has become asymmetric, and the eye that appeared briefly before landfall has disappeared. Radar from Gran Piedra, Cuba still shows several well-formed spiral bands on the east and south sides of the storm. However, the northwest side of the storm shows evidence that dry air is interfering with Gustav's organization.

http://www.wunderground.com/blog/JeffMasters/comment.html?entrynum=1047&tstamp=200808

[GoesTo11]

1. Great news.

[Javaman]

2. so it's one of those dry hurricanes, huh?

:rofl: