05 November 2010

Tomas re-intensifies as it passes between Haiti and Cuba...

Since my last update on Monday, Tomas behaved pretty much as expected, and continues to do so.  Copying directly from that update: "By later in the week, Tomas is forecast to regain hurricane status and very slowly make its way northward toward Haiti".  Well, Tomas has become a hurricane again, and is currently near the tip of Haiti's southern peninsula.  At 15Z, the intensity was 75kts/987mb and tracking NNE at 10kts.  By far, the biggest concern with this storm is the very heavy rainfall over Haiti, eastern Cuba, and the Dominican Republic.  There are many locations with Hurricane Warnings, please check http://www.nhc.noaa.gov/storm_graphics/AT21/refresh/AL2110W5+gif/ for the latest.

By early next week, Tomas will become entangled with a mid-latitude trough and become extratropical.  But impressively, it's already been around as a numbered system for nearly 7 days, and probably will be around for another 3-4.  My colleague Phil Klotzbach pointed out that "it would be the second most NSD [Named Storm Days] generated by a storm forming on or after October 29 since aircraft recon began in 1944.  The most NSD generated by a single storm forming after October 29 is Hurricane Lili back in 1984, which generated an impressive 11.75 NSD".  So, yet another anomaly for this incredibly active season that will go into the record books with the company of 1933, 1995, and 2005.

Please visit my tropical Atlantic headquarters.

01 November 2010

Tomas weakens in the central Caribbean...

For a brief period early Sunday morning, Tomas reached an intensity of 85kts (Cat 2), but has since weakened significantly in the face of hefty vertical shear.  In fact, the low-level circulation is completely exposed and the convection is displaced well to the east.  As I write this, there is a resurgence of deep convection over the center, but it's still getting pushed off to the east.  At 15Z today, the intensity is 40kts/1005mb (a weak tropical storm) and is forecast to remain weak for another day or so until the shear relaxes and the storm can regain its organization.  By later in the week, Tomas is forecast to regain hurricane status and very slowly make its way northward toward Haiti.

Reaching the 19th named storm is extremely rare, but having a named storm in November is not so rare.  In recent years, November storms include Ida '09, Paloma '08, Noel '07, Gamma '05, Delta '05, Otto '04, Nicholas '03, etc, etc, etc.  The end of the official hurricane season is the end of November, but nature doesn't always obey that arbitrary limit... recent post-November storms include Olga '07, Epsilon '05, Zeta '05, Odette '03, and Peter '03. 

Please visit my tropical Atlantic headquarters.