Sun Sentinel Palm Beach Edition
Impact odds increase
Latest projections make South Florida a prime target
Hurricane Irma increased the odds it will make landfall on the southern part of the Florida peninsula Sunday as a “dangerous major hurricane,” although it remains unclear where the main blow will fall, the National Hurricane Center said.
The hurricane maintained its 175-mph strength and is expected to remain a major hurricane for the next three days. A major hurricane is one of at least Category 3 strength, which means winds of at least 111 mph, capable of causing “devastating damage,” according to the hurricane center.
The forecast track shifted slightly to the west in the hurricane center’s 5 p.m. Thursday advisory and held that course in the 8 p.m. advisory. Although South Florida is no longer at dead center, it is just east of the
center. The reach of hurricane-force winds grew to a width of 140 miles, reducing the chance that areas in the hurricane’s path could escape with a glancing blow from tropical-force winds.
“It has become more likely that Irma will make landfall in southern Florida as a dangerous major hurricane, and bring life-threatening storm surge and wind impacts to much of the state,” the hurricane center said.
South Florida residents should take shelter by tonight and stay there, with the outer bands of Hurricane Irma expected to arrive Saturday morning, bringing hazardous winds and the risk of tornadoes, the National Weather Service said.
Arriving at the front of the storm will be tropicalforce winds, with speeds of 39 mph or more and much higher gusts, capable of causing damage and injuries.
“It becomes very, very dangerous to be outside,” said Kevin Sharfenberg, science and operations officer for the National Weather Service in Miami. “People should be sheltered at that point. A lot of emergency services stop operating for the safety of their crews when we get to these winds.”
“We’re really telling folks to be ready and be where they’re going to ride out the storm by Friday night. As we get into Saturday, those outer bands will starts to rotate over South Florida, and that’s a favorable situation for some tornado activity.”
A hurricane watch was issued for South Florida late Thursday morning, as the state faced its gravest hurricane threat in a generation.
Evacuations in coastal areas, places prone to flooding and mobile homes were ordered in Miami-Dade, Broward and Palm Beach counties.
The watch extends from Jupiter Inlet in northern Palm Beach County around the peninsula to Bonita Beach, just north of Naples, as Hurricane Irma maintained a course that could bring devastating winds, rain and waves to South Florida as early as Saturday. The watch includes the Florida Keys and Lake Okeechobee.
The latest forecast from the National Weather Service calls for South Florida to experience wind speeds greater than 110 mph, with wind speeds higher to the south and lower inland. But the weather service said the entire southern part of Florida at risk and that no one should consider one area safer than another.
“The threat is pretty equal right now across all of South Florida, west coast, central and east coast and into the Keys,” Sharfenberg said. “We don’t want to try to slice the baloney too thin here and say it’s more this side of the state or that side of the state. This is a large and very dangerous hurricane and should be treated as such.”
Coastal Palm Beach County can expect winds of 105 to 125 mph, with gusts to 160 mph; coastal Broward can expect winds of 110 to 130 mph, with gusts to 155 mph; and coastal MiamiDade can expect winds of 115 to 135 mph, with gusts to 170 mph.
Inland areas are forecast to see lower wind speeds, although much depends on the hurricane’s course. Inland Palm Beach County could see wind speeds of 90 to 110 mph, with gusts to 140 mph; inland Broward could see winds speeds of 95 to 115 mph, with gusts to 155 mph; and inland Miami-Dade could see wind speeds of 100 to 120 mph, with gusts to 155 mph.
A storm surge of up to nine feet is possible along the southern Florida coast, with the risk worst in Collier County and southeastern Miami-Dade County, although the threat extends through northern Palm Beach County. Although this storm surge threat doesn’t approach the monstrous surges of up to 20 feet feared in some Caribbean islands, it could still cause substantial flooding and damage.
“The deepest water will occur along the immediate coast in areas of onshore winds, where the surge will be accompanied by large and destructive waves,” the hurricane center said.
The rain threat appears worst on the southeast coast, with eight to 12 inches of rain possible, and up to 20 inches in isolated areas, according to the weather service. Although this isn’t on the scale of what Harvey brought to Texas, it’s enough to cause serious flooding.
Thousands of South Florida residents are fleeing north, generating heavy traffic on Interstate 95 and Florida’s Turnpike.
Meanwhile, South Florida started shutting down. Sawgrass Mills mall announced it would close at 6 p.m. Thursday.
The weather service said South Florida could face “structural damage to sturdy buildings, some with complete roof and wall failures. Complete destruction of mobile homes. Damage greatly accentuated by large airborne projectiles. Locations may be uninhabitable for weeks or months.”
Gov. Rick Scott called up an additional 3,000 members of the Florida National Guard on Thursday, making the announcement immediately after the watches were posted.
“We are expecting our state to have major impacts from Hurricane Irma and we are taking aggressive actions to make sure Florida is prepared,” he said.
A hurricane watch, which is typically issued 48 hours before the storm hits, means hurricane conditions are considered possible within that time frame. If they are considered likely, the condition is upgraded to a hurricane warning.
The timing of the hurricane’s possible arrival is also uncertain. Tropical storm conditions, which means winds of 39 to 73 mph, are possible in South Florida starting late today or Saturday, according to the National Weather Service in Miami. If the hurricane comes close enough to deliver-hurricane-force winds, they could arrive Saturday or Sunday.
Although South Florida lies within the center of the forecast cone, the hurricane center stressed that the forecast of the storm’s likely path has become less clear at the three-day mark, when it could be near South Florida, due to a lack of certainty about the an upperlevel trough over the southeastern United States. The storm is currently being held on a western course by a zone of high pressure to the north. But this highpressure zone is expected to be eroded in next few days, as the low-pressure trough moves in, allowing the hurricane to hook to the north.
The average forecast error at four days out is 175 miles, and at five days out it’s 225 miles.
The storm could produce eight to 10 inches of rain this weekend, generating local flooding but nothing on the scale of the catastrophic floods experienced by Houston, according to the South Florida Water Management District, which handles flood control from Orlando to the Keys.
The district is lowering the water levels in drainage canals to accommodate the rain, said John Mitnik, chief engineer for the district.
President Donald Trump declared an emergency for Florida, freeing up federal funding to help the state defend itself against the huge storm. Among possible emergency measures would be shoring up beach dunes, building emergency berms and planning for potential evacuations, according to a news release from the governor’s office.
“Our state emergency management officials are working with our federal and local partners to prepare for any potential impacts from this dangerous storm,” Scott said. “And it is crucial that we have access to every available resource to protect our families and communities.”