Irma Weakens To A Tropical Storm, But Danger Persists

Irma, which made landfall in the Florida Keys yesterday as a Category 4 hurricane, has now been downgraded to a tropical storm. The system, which is now 644km wide, may have lost some strength, but it's continuing to produce heavy winds and rain as it marches northwards towards Georgia.

GOES-16 satellite image of Hurricane Irma, taken on Sunday 10 September 2017 at 6:00PM ET (Monday 11 September 2017 at 8:00AM AEST). (Image: NOAA/GOES)

As of 8:00AM local time (10:00PM AEST), Irma's centre was about 169km north-northwest of Tampa and about 48km north-northeast of Cedar Key. The storm came ashore on Sunday afternoon in southwest Florida as a Category 4 hurricane, causing extensive damage to the Florida Keys, Miami, Naples and several other areas. Incredibly, Irma was a hurricane for 11.25 days, which is the most since Ivan in 2004.

But Irma isn't done yet. Now a tropical storm, the system is still capable of producing hurricane-strength gusts, and maximum sustained winds of about 113km/h. The storm has a particularly large wind field, extending across the entire Florida peninsula.

"Irma is moving toward the north-northwest near 18 mph (30 km/h) and this motion is expected to continue through Tuesday," noted NOAA's National Hurricane Center in a public advisory. "On the forecast track, the center of Irma will move near the northwestern coast of the Florida Peninsula this morning, cross the eastern Florida Panhandle into southern Georgia this afternoon, and move through southwestern Georgia and eastern Alabama tonight and Tuesday."

A street is flooded near the ocean after Hurricane Irma passed through Naples, Florida, on Saturday local time. (Image: AP)

From here, the storm will likely weaken further still, and it will probably be downgraded to tropical depression by Tuesday afternoon local time, according to NOAA.

Damage in Marco Island, Florida. (Image: AP)

Several storm surge warnings are still in effect, the most urgent extending from South Santee River to Fernandina Beach (1.2 to 1.8m) and Clearwater Beach to Ochlockonee River (1.2 to 1.8m).

Heavy rains are predicted for northern Florida and southern Georgia, which could see an additional seven to 15cm with total amounts reaching between 20 to 38cm. Tornadoes are possible in northeast Florida, and southeastern portions of Georgia and South Carolina through today.

Officials in Jacksonville issued a flash flood emergency yesterday. Heavy rains are causing rivers to swell, and significant flooding is possible over the next five days, both along the Florida peninsula and in southern Georgia.

An incredible shot of Irma's eye as seen from the Sentinel-2A satellite on 9 September 2017. (Image: Antti Lipponen/Flickr)

As daylight returns to Florida, the damage inflicted by Irma is becoming clear. At least four people were killed by the storm in Florida, and 3.3 million people are currently without power. In Miami, streets were turned into rivers as water poured in from the storm surge, and construction cranes collapsed under the force of 180km/h winds. The Florida Keys were hit particularly hard by Irma, with reports of massive damage caused from a combination of wind, rain and surge. A huge airborne relief mission was dispatched yesterday to assist with recovery efforts.

A tropical disturbance has emerged a few hundred km west of the Cabo Verde Islands. (Image: NOAA)

As all this is happening, meteorologists are nervously watching a newly formed disturbance in the east Atlantic that has a 30 per cent chance of developing into a cyclonic storm in the next 48 hours. Sigh.

[NOAA National Hurricane Center, New York Times, Miami Herald, Florida Key News]