31 July 2007

Bermuda disturbance upgraded to Tropical Storm Chantal...

At 03Z this morning (11pm EDT), the disturbance I mentioned yesterday near Bermuda was upgraded to TD3, then to TS Chantal just twelve hours later.  The latest intensity estimate is 45kts and 999mb.  It's located at 40.2N 62.7W, or about 1000 miles east of New Jersey, and heading NE at 25kts.
It is forecast to continue zipping off to the northeast as a tropical storm, but gradually lose its identity over the next 24 hours as it gets absorbed by an encroaching trough.

The tropical wave approaching the Lesser Antilles is looking much less organized today, with minimal convection and only a poorly-defined mid-level circulation presently located around 12N 51W.  It's tracking W at 12kts and still has a fairly good chance at further development.  The central pressure is estimated at 1010mb but is in a very favorable environment for intensitification.

The wave behind the aforementioned one is still notable in the satellite imagery and surface analyses, and is now at about 12N 36W, tracking W at 12kts.  And lastly, an easterly wave with some mid-level vorticity is just exiting the African coast now.

Please visit my tropical Atlantic headquarters.

30 July 2007

Three areas to watch...

There is an area of disturbed weather that migrated northward from Cuba and is now just west of Bermuda.  It's moving NE at 12kts and will only have a brief time to get organized before getting absorbed by an approaching trough and SSTs plummet below 20C.  The present structure suggests that it's subtropical, and a transition to tropical is possible, but not likely.

There is also a potent easterly wave near 11N 47W.  It's moving W at 10kts and has a 1009mb Low embedded within it.  It left the African coast about a week ago, and has not been terribly impressive until today.  SSTs are around 27-27.5C and will be increasing with time as the wave heads westward (up to 28-28.5C). It's in very little vertical shear, and cloud tops over the center have been sustained at -60C.  This has the potential to become the season's first hurricane later this week.

In addition, a second easterly wave at about 29W is on the heels of the first... it left Africa earlier this weekend.  I was unable to find a single model that forecast development of this wave, but it still bears watching.

Should any or all of these get named, the next names on the list are Chantal, Dean, and Erin.

Please visit my tropical Atlantic headquarters.

03 July 2007

Disturbance in deep tropics...

An African Easterly Wave that left the coast of Africa on June 28 has been making its way across the deep tropical Atlantic, presently at about 11N 40W.  It's heading WNW at 12kts, is over 26.5C SST, and there's little vertical wind shear.  The MSLP is estimated at 1014mb.

Over the next few days, the system is expected to continue tracking WNW toward the Lesser Antilles.  If a closed circulation and persistent central deep convection exist, it will be upgraded to TD3, and if sustained winds in the circulation reach 35kts, it will become TS Chantal.  For reference, TD3 formed on this date in 2005 (became Cindy).  2005's season was memorable for its FOUR Category 5 hurricanes: Emily (formed July 11), Katrina (formed August 23), Rita (formed September 18), and Wilma (formed October 15).

Please visit my tropical Atlantic headquarters.