Caribbean disturbance struggling again

Once again, the tropical disturbance in the western Caribbean sea southwest of Jamaica has fallen on hard times. It's refreshing for a change to see a system that doesn't develop when conditions seem to favor devlopment; this is typical behavior in most hurricane seasons, but certainly has been lacking in the Hurricane Season of 2005! The disturbance's deep convection has decreased considerably since last night, despite warm water beneath the system and somewhat favorable wind shear overhead. Wind shear remains in the 5 - 10 knot range, and has not decreased as forecast. Upper level outflow is poor, and the upper-level anticyclone overhead that was observed yesterday has grown weaker. The reconnaissance flight scheduled for this morning was moved to this afternoon, and they are currently investigating the system. There is some increased thunderstorm activity building on the southwest side of the disturbance this morning, and we may see a reapeat of yesterday, when the disturbance got better organized through the day, only to fall apart at night.

None of the computer forecast models develop the system, although they do still forecast a more favorable upper-level wind pattern to develop Friday and Saturday. However, the disturbance is approaching the Yucatan Peninsula, and development will probably be hampered by passage over the Peninsula. Dry air being pulled off of the Yucatan may also be a problem. The disturbance is unlikely to develop into anything more than a minimal tropical storm through Saturday. It may have a better chance for development once it enters the Gulf of Mexico early next week, although this is not assured--wind shear and more dry air may be problems for it.


Figure 1. The BAMM model takes the Caribbean disturbance into the Yucatan Peninsula. The GFDL model disippates the system immediately.

Southeast U.S.
Several of the global computer models have been persistently forecasting for the past three days that a tropical storm may form in the waters east of the Carolinas or Florida early next week. Any system forming in this region would be forced westward or west-southwestward into the Southeast Coast by a strong ridge of high pressure building in. There is as yet no sign of this development occurring, but we should watch the waters off of the Southeast coast the next few days.

Africa westward
The ITCZ is active in the region extending from the African coast westwards for 1000 miles. There are currently no suspect areas to focus on.

Hawaii
Hawaii is watching Tropical Storm Kenneth, which is expected to pass though the Islands Friday and Saturday as a tropical depression, and may bring heavy rains and the threat of flash flooding to the islands. Tropical depressions that have passed though the islands in previous years have caused serious flooding problems.

Baja
The Baja Peninsula is watching newly-formed Tropical Tropical Storm Otis, which may strike the central Baja Peninsula on Sunday. Otis is also a threat to bring heavy rains and flooding to Arizona and northern Mexico early next week.

China
Super Typhoon Langwang, a small but intense typhoon with 150 mph sustained winds, is headed towards China and may hit northern Taiwan as a Category 4 storm on Sunday. Longwang is expected to gradually weaken but still hit mainland China on Monday as a Category 3 storm.

Jeff Masters