By:
Dr. Jeff Masters,
3:21 PM GMT on December 19, 2006
The
hurricane season of 2006 has a new tropical storm. No, it's not one of those rare December tropical storms. The new storm occurred back in July, according to a post-season analysis
released by the National Hurricane Center Friday. The unnamed storm formed about 240 miles southeast of Nantucket, Massachusetts on July 17 from the remains of a cold front that had pushed off the East Coast on July 13. The unnamed storm started off as an extratropical storm, then passed over the warm 28-29 C waters of the Gulf Stream, which helped it make the transition to a warm-cored tropical storm. At its peak intensity, the unnamed storm had winds of 50 mph at the surface. As it moved northeastward, it passed into much colder waters, and died 24 hours after becoming a tropical storm. There were no reports of damage or injuries.
Figure 1. Unnamed tropical storm of July 17, 2006 (labeled "Extratropical (subtropical?) low" in my blog from July 17).
It is often difficult to be certain in real time if a short-lived storm is fully tropical and deserves a name. If the storm is not a threat to land, NHC will usually play it conservative, and rely on an end-of-season post-analysis using data that is not available in real time to determine if a borderline system was a tropical storm or not. In
my blog from July 17 of this year, I noted, "To my eye, the system is probably a subtropical storm, and technically should be classified as Subtropical Depression Two. However, is it difficult to tell for sure, and the NHC is conservatively not naming it, since it is headed towards colder water and has little chance of becoming a full tropical storm." This is the second year in row NHC has analyzed a new tropical storm after the season was over. Last year, "Should have been Tammy" got rooked out of name; this year's storm--"Should have been Beryl"--brings the statistics for the 2006 Atlantic hurricane season exactly to average for named storms--ten--and one below normal for hurricanes, five.
For information about
Tropical Cyclone Bondo near Madgascar, which is near Category 5 intensity, see Margie Kieper's excellent
View From the Surface blog. The cyclone passed only 37 km south of
Agalega, Mauritius, today.
Jeff Masters