for National Geographic News
As a strengthening Hurricane Dolly heads for landfall today near the Texas-Mexico border, some meteorologists see indications that the rest of this year's hurricane season could be very active.
As of noon eastern time today, the center of Hurricane Dolly was about 35 miles (48 kilometers) northeast of Brownsville, Texas.
The storm's strongest winds were blowing at about 96 to 110 miles (154 to 177 kilometers). That makes Dolly a Category 2 storm on the Saffir-Simpson scale, which rates hurricanes from 1 to 5 based on the damage they are likely to cause.
Dolly's winds could increase before the storm comes ashore around 1 p.m. eastern time, said Christopher Juckins, a meteorologist at the National Hurricane Center in Miami, Florida.
The storm is over warm water in the Gulf of Mexico—which could allow it to intensify—and there are no upper-level winds that would inhibit its development.
Experts believe Hurricane Dolly's impact will be minimal, because it likely will go ashore in an area that is not heavily populated. Other July hurricanes in past years have been much more powerful than Dolly.
Still, the formation of Hurricane Dolly—as well as Hurricane Bertha and tropical storm Cristobal earlier this month—make July 2008 unusual, meteorologists say.
On July 19, Bertha, Cristobal, and Dolly were all active tropical weather systems, noted meteorologist Jeff Masters of Ann Arbor, Michigan, founder of the commercial forecasting Web site Weather Underground.
That's the first time three named systems have been active on the same day since the practice of naming hurricanes began in 1950, he said.
The two seasons during which July was more active—1933 and 2005—ended up being the two most active hurricane seasons on record.
"All three years—1916, 1933, and 2005—had five major hurricanes. I'd say the odds of more than one major hurricane hitting us are enhanced this year."
Phil Klotzbach, a meteorologist at Colorado State University in Fort Collins, said early-season activity usually isn't an indicator of how the rest of the season will develop—unless storms are already forming in the so-called deep tropics east of Puerto Rico.
And that's what is happening this year, he said.
"When you have storms like Hurricane Bertha—which formed in the deep tropics—that tells you that things are trying to go very early," Klotzbach said. "That tells you that prior to the first of August, things are ripe for formation."
Masters of Weather Underground also noted that Hurricane Bertha was a bizarre storm. It was named on July 3, became a Category 1 hurricane on July 7, and retained its status as a named system until July 20.
Bertha also surprised meteorologists by suddenly intensifying to a Category 3 only a few hours after it reached hurricane status.
In addition, Bertha also developed near the Atlantic Ocean's Cape Verde Islands, the birthplace of some of the most severe storms on record.
These so-called Cape Verde hurricanes don't usually develop until later in the season—making Bertha the earliest Cape Verde storm on record, Masters said.
Also: Hurricane Forecasters Stick to "Busy" 2008 Prediction