Tuesday, November 24, 2015

Hurricanes: Why the wait

Still waiting for that first Atlantic hurricane - so what's not going on down there?

Hurricanes: Why the wait


Humberto still was a few puffs away from becoming the first hurricane of the Atlantic season, weighing in with peak winds of 70 m.p.h. as of 4 p.m. – 4 m.p.h. shy of the  minimum threshold for qualifying as a Category 1.

What was forecast to be a wild season has been a coastal resident’s dream so far.

In the era of satellite reconnaissance – and that’s a critical distinction – this already has become the second-longest wait for a hurricane to form in the Atlantic Basin, consisting of the Atlantic, Caribbean Sea, and Gulf of Mexico.

“We’re way behind the curve,” said Dennis Feltgen, a meteorologist at the National Hurricane Center who deals with the media, pointing out that typically by now three hurricanes would have formed.

All the major preseason outlooks had called for an active season with well-above normal numbers of tropical storms – those with winds of at least 39 m.p.h. – and hurricanes.

Tropical-storm numbers are close to normal, but the hurricane lull is a puzzling one, since Atlantic sea surface temperatures are warm, and no El Nino has formed in the Pacific. During El Nino warming, winds from the west tend to shear off hurricanes.

“This is a head scratcher,” said Feltgen.

Typically, the season picks up in mid-August as the Cape Verde gets cooking, but that hasn’t happened.

Waves bounding off Africa have encountered dry air and haven’t been able to get the spin they need to become dangerous, said Feltgen.

Closer to the United States, an area of lower pressure over the Southeast has generated winds that have sheared off potential storms.

Although storms can form in the western part of the basin into November, coastal residents and property owners should be glad to learn that the Cape Verde season typically fades during the third week of September.

The modern record for the latest-forming first hurricane is Sept. 11, 1967, and Humberto still is forecast to finish second.

The all-time record was Oct. 8, 1905, however that needs an *. Before satellite monitoring began in the 1960s, any number of hurricanes could have formed without detection.

It is impossible to say what the rest of the season, which ends Nov. 30, will bring. But evidently it is providing yet another lesson in humility for the long-range forecasters.

Inquirer Weather Columnist
We encourage respectful comments but reserve the right to delete anything that doesn't contribute to an engaging dialogue.
Help us moderate this thread by flagging comments that violate our guidelines.

Comment policy:

Philly.com comments are intended to be civil, friendly conversations. Please treat other participants with respect and in a way that you would want to be treated. You are responsible for what you say. And please, stay on topic. If you see an objectionable post, please report it to us using the "Report Abuse" option.

Please note that comments are monitored by Philly.com staff. We reserve the right at all times to remove any information or materials that are unlawful, threatening, abusive, libelous, defamatory, obscene, vulgar, pornographic, profane, indecent or otherwise objectionable. Personal attacks, especially on other participants, are not permitted. We reserve the right to permanently block any user who violates these terms and conditions.

Additionally comments that are long, have multiple paragraph breaks, include code, or include hyperlinks may not be posted.

Read 0 comments
comments powered by Disqus
About this blog

Tony Wood Inquirer Weather Columnist
Also on Philly.com
letter icon Newsletter