Irma could become a Category 4 or 5 storm before reaching the Antilles Islands next week. But it's too early to know whether the storm will make landfall.
Hurricane Irma is intensifying as it makes its way across the Atlantic. It's now a major Category 3 storm, according to the National Hurricane Center.
It's too early to know whether the storm will make landfall in the Caribbean, Mexico, or the US, though some models suggest it could head toward the Eastern seaboard or Gulf of Mexico.
"It's way too early to say for sure if Irma is going to have any impacts on the United States, but anytime the forecast models are predicting a potentially strong hurricane headed northwest across the tropical Atlantic, I'd pay attention," Phil Klotzbach, a meteorologist at Colorado State University who specializes in Atlantic hurricane forecasts, told Business Insider.
An analysis of Irma early Thursday morning showed 70 mph winds, making it a tropical storm. But by 11 a.m., sustained wind speeds had jumped to almost 100 mph with some higher gusts, causing it to become a Category 2 hurricane. By 4:30 p.m., Irma had sustained winds at 115 mph, making it the season's second major hurricane — a term used for storms that reach Category 3 storms or above.
Michael Ventrice, a meteorological scientist at The Weather Company (the group behind the Weather Channel and Weather Underground) told Business Insider that "it could be the strongest hurricane of the year."
Projections for where Irma will go from here vary greatly — if it turns north, it could veer off into the Atlantic, away from the US.
But certain projections show that a more direct path toward land is possible. A few models suggest Irma could head towards the East Coast. But Ventrice said that "some of the better performing models that are correctly handling [Irma's] initial formation are more favorable towards the Gulf of Mexico" — the region that is still suffering from Harvey.
A combination of conditions — including a warm tropical Atlantic, a weak wind shear, and a change from drier to wetter weather — made it easy for Irma to pick up strength, according to Klotzbach. The storm could put us far ahead of the average accumulated cyclone energy (a measure of the energy of tropical cyclone systems) for this time of year, he said.
Both CSU and The Weather Company predicted an unusually active hurricane season this year. Irma is the fourth hurricane of 2017, but the average date of the fourth hurricane in a year is September 21. The peak of the season is around September 10.
Klotzbach said half of the season's cyclone energy usually occurs in September, meaning major hurricanes are likely still to come.
Big hurricanes are usually defined by their wind force, but as we saw with Harvey — which made landfall as a Category 4 hurricane but caused most of its damage due to heavy rain — the number doesn't always accurately predict a storm's impact.
Since Irma formed so far to the east, it's a real test for weather prediction, according to Ventrice. Forecasters will have a better idea of what to expect from the hurricane b the middle of next week.
At the same time, meteorologists are also monitoring a disturbance in the southwestern Gulf of Mexico that could bring additional rainfall to the already flooded Texas and Louisiana coasts sometime early next week.