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Irma intensifies to an ‘extremely dangerous’ Category 5 hurricane on its track toward the U.S.

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September 5, 2017 at 8:55 a.m. EDT

Hurricane Irma strengthened overnight to a dangerous Category 5 as it barrels toward the Greater Antilles and Southern Florida. It’s likely that Hurricane Irma will affect the U.S. coast — potentially making a direct landfall — this weekend.

Tuesday morning, NOAA Hurricane Hunters found the storm’s maximum wind speeds are 175 mph. It now ranks among the strongest hurricanes ever recorded in the Atlantic Ocean. Forecasts suggest it will reach southern Florida and the Gulf of Mexico this weekend.

Hurricane warnings have been issued for portions of the Leeward Islands and the Greater Antilles, including Puerto Rico.

The National Hurricane Center called Hurricane Irma an “extremely dangerous” storm Tuesday morning. “Preparations should be rushed to completion in the hurricane warning area,” the forecasters wrote in their 8 a.m. update. Devastating winds, a major storm surge and flash floods are all likely in the Leeward Islands and Puerto Rico in the next 48 hours.

Over the weekend, the forecast track for this potentially devastating hurricane shifted south and west. It seems likely now that the storm will affect or strike the U.S. coast early next week, although meteorologists don’t know exactly where. Florida and the Gulf Coast continue to be at risk. The East Coast, including the Carolinas and the Delmarva Peninsula, are also potential candidates for landfall — or, at the very least, heavy rain, strong winds and coastal flooding.

At 8 a.m. Tuesday, Irma was located about 280 miles east of the Leeward Islands and moving to the west at 14 mph, the hurricane center said.

Unfortunately, Irma remains in a favorable environment for strengthening, with warm sea surface temperatures and favorable upper-level winds allowing the storm to stay very strong in the coming days. The National Hurricane Center predicts the storm will strengthen even more — to 180 mph — making it the second-strongest hurricane on record in the Atlantic Ocean, behind Hurricane Wilma in 2005.

Late Sunday afternoon, Hurricane Hunters began regular flights into Irma, providing extremely valuable data that has improved forecasts. The immediate track of Irma through the middle of the week is not much of a question at this point; an area of high pressure is firmly in place over the central Atlantic, preventing Irma from recurving and escaping out to sea. That high won’t move much over the next several days, steering Irma due west into the Leeward Islands by midweek.

Florida declares state of emergency as Hurricane Irma intensifies to a Category 5 storm

Both the American and European models have started to show more consistency in a forecast track for Irma that increases the chances of impacts on the U.S. coast. Irma will probably continue to be suppressed by the strong Atlantic high pressure beyond Wednesday, keeping the storm at major hurricane status and on a trajectory that places the storm in close proximity to Florida by next weekend.

Potential U.S. impacts

Forecasts beyond the five-day mark are still full of uncertainties, but the trend in both the American and European ensemble members is concerning.

It remains difficult to pinpoint if and where Irma will make landfall in the United States, but Florida is becoming the likely target. There is strong agreement in Irma’s path through Friday, at which point Irma will probably be a major hurricane located just to the south of the Bahamas.

The National Hurricane Center is forecasting tropical storm conditions to begin affecting Florida by Friday evening. All of the usual hazards are at play here; strong winds, heavy rain and dangerous storm surge. Storm surge may become the largest concern over the next few days, given the amount of time that Irma is spending over open water combined with the low-lying topography of southern Florida.

Again, it should be noted that the forecast track for Irma will continue to change as we start to receive more aircraft data on the storm and as the large-scale environment features become more clear. At this point, residents from the gulf all the way to Maine should take special interest in forecast updates for Irma throughout the week.

Brian Murphy contributed to this report.