Stormier Days May Lie Ahead
Aug 6, 2008
Hurricane season’s early activity has 2 forecasters upping their predictions
By Anna Scott
Herald Tribune--August 6, 2008
Florida has so far been spared from being hit in an active early hurricane season.
But as the season peaks over the next 10 weeks, the conditions that fueled the early-season storms could mean Florida and other coastal areas will be threatened by more hurricanes than experts earlier predicted.
One of the leading forecasting groups on Tuesday increased its prediction of named storms to 17 from 15 and its predicted number of hurricanes to 9 from 8.
Forecasters at Colorado State University say rainfall over western Africa has been above average, meaning there are more storms reaching the ocean that could potentially become hurricanes. Those storms are encountering water that is several degrees warmer than normal, which provides fuel for them.
And a low-pressure system stretching across the tropics, the region between the west coast of Africa to the outer edge of the Caribbean, is creating an unstable environment conducive to storms.
"We had a very active early season," said Phil Klotzbach of Colorado State University, who issued the updated report Tuesday. "Usually that doesn’t correlate with the rest of season unless it happens in the tropics, and that’s what we’ve seen."
Klotzbach said Hurricane Bertha was the most troubling sign this season. The storm formed off Cape Verde in early July, making it the earliest hurricane on record to form so far east in the Atlantic.
Only in four other years has a storm formed in the tropics in July: 1926, 1961, 1996 and 2005.
There were least six major hurricanes in each of those years.
Also, at two and a half weeks, Bertha broke the record for the longest-lasting storm. That, too, is a sign the atmosphere is prepared to incubate more storms.
In total, five named storms, including two hurricanes, formed before Aug. 1 — an above-average count.
While the forecasters point to a likely increase in expected hurricanes, they point out that the season still does not bear the markings of the record-breaking 2004 or 2005 seasons. And, unlike those years when hurricanes slammed Florida, so far this year, unpredictable steering winds have pushed storms elsewhere.
John Cangialosi, forecaster at the National Hurricane Center, said each of the five named storms this season steered clear of Florida because of a different factor — and that cannot be counted on to protect the state through the end of the season, Nov. 30.
The subtropical ridge, an area of pressure, generally steers storms toward or away from Florida. It is what pushed Bertha back out to sea before the storm could set a path to the east coast, and it is what forced Hurricane Dolly to move southwest into Texas and Mexico.
"While it might be favorable in some cases, it might hurt you in other cases," Cangialosi said. "It really depends on where the storm is."
Most major hurricanes have hit Florida in September, when 18 storms have landed with at least Category 3 strength over the years. In October, nine major hurricanes have landed in Florida
In addition to the Colorado State update, forecasters at the London-based Tropical Storm Risk, one of the biggest private forecasters in the insurance industry, have been raising their predictions for the season since December, releasing their highest number yet on Tuesday.
They are calling for more than nine hurricanes for the total season, about seven more in the remaining four months of storm season.
Kenneth Reeves, forecasting director for AccuWeather.com, said the season had already brought one more storm than expected.
Federal forecasters plan to release their update on Thursday, and National Hurricane Center specialists said the large amount of storm activity in July would be a factor.
In June NOAA said there was a 90 percent chance of an above-average season of 11 named storms.
With five named storms already, NOAA is likely to raise its hurricane forecast, too.