Latest Projections Show Hurricane Irma Headed For Florida

As Hurricane Irma continues to move  west as a Category three storm, in what still is said to be an indeterminate path, according to the latest projections from Met Scientist Michael Ventrice, it now looks like Florida has the highest probability of a US landfall…

Latest 12Z Calibrated ECMWF Ensembles indicates that Florida now has the highest probability to see Hurricane #Irma impacts/landfall ???? pic.twitter.com/YVgjueeKYx

— Michael Ventrice (@MJVentrice) September 3, 2017

…though that doesn’t mean the Gulf of Mexico can rest easy. Hurricane forecasting is notoriously inaccurate one or two weeks out...

Not a shift in guidance anyone wanted to see. Looks like #Irma threat growing again for Gulf States. Forecast remains extremely difficult https://t.co/sZs5t2ppHJ

— Michael Ventrice (@MJVentrice) September 3, 2017

Before it nears the US, however, the storm is headed toward the Northern Caribbean, threatening to bring flooding rain and damaging winds to the Leeward Islands. Preparations for the storm should already be taking place in these areas, according to Accuweather.com.

“Rain and gusty winds may start as early as Tuesday,” AccuWeather Senior Meteorologist Rob Miller said.

According to Accuweather, Irma’s intensity has vacillated over the past few days. But the storm is expected to strengthen to a category four hurricane with sustained winds of 130-156 mph as it approaches the islands. Thereafter, the storm will turn to the north and west over the coming days. This track will put Antigua and Barbuda, Montserrat, St. Kitts and Nevis, Anguilla and the British Virgin Islands, in the brunt of the storm"s rain and wind spanning Tuesday and Wednesday.

Hurricane watches issued for portions of the Leeward Islands. Latest information on #Irma available at https://t.co/tW4KeGdBFb pic.twitter.com/BPiAPelf3D

— NHC Atlantic Ops (@NHC_Atlantic) September 3, 2017

Cruise and shipping vessels in the hurricane’s path will need to reroute.

Later in the week, Irma will move close to Puerto Rico and Hispaniola with the worst of the storm expected to miss the islands to the north. Even so, rough surf, gusty winds and heavy rain will increase.

Experts are concerned that the Turks and Caicos Islands and the Bahamas could face dangerous conditions at the end of the week and into the weekend as Irma passes nearby or possibly through the islands. Impacts will be severe if Irma maintains its strength and passes over them.

Ultimately, the storm could land in Florida, Georgia, the Carolinas or even closer to the Delmarva Peninsula. Or it could curve northward and miss the east coast entirely.

“The eastward or northeast progression of a non-tropical system pushing across the central and eastern U.S. this week will highly impact the long-range movement of Irma,” AccuWeather Hurricane Expert Dan Kottlowski said.

How fast or slow this non-tropical system moves will determine whether Irma takes a west-northwest path toward the southern Atlantic Seaboard or gets steered north and away from land.

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Readers may be wondering, if the storm slams southeast Florida, as is looking increasingly likely. Well, the Miami Herald spoke with one engineer who built a “dynamic” weather forecasting model that incorporates data like rainwater evaporation rates and how much of a given surface area is paved.

“Omar Abdul-Aziz, an engineer and assistant professor at West Virginia University, has done just that with a new model he built while at Florida International University as part of a state-funded project to improve hurricane loss models. At the request of the Herald, he agreed to run three rainfall scenarios that might resemble Hurricane Harvey.

The maps he produced stretch from Homestead north to Port St. Lucie, not including barrier islands which are separate land masses, and depict flooding after 48 hours from 20 inches of rain, 30 inches of rain, and 40 inches of rain.

Because the maps cover a large area, they don’t show flooding at street level. But Abdul-Aziz said they do provide a far more accurate picture of what would happen across the region.”

If his models are accurate, residents of densely populated cities like Miami might want to start bracing for floods. Abdul-Aziz found that floodwaters in parts of Miami, Hialeah, South Dade and Fort Lauderdale could rise between nine and 17 inches at least with this amount of rain. And with 40 inches of rain, flooding in those same neighborhoods, as well as many more, rises to between 23 inches and more than three feet — enough to begin damaging houses and partially submerge cars.

“Because of the flat land and low elevation, water does not move fast. It goes slow and the drainage capacity is not designed to take that much rainfall,” he said.

To build the model, funded with $533,000 from the state, Abdul-Aziz used the Environmental Protection Agency’s latest stormwater management model, which has been used since the 1970s to help communities plan water and sewer systems. They include local hydrology, land cover, ground level and local climate, but cover a smaller area.

Abdul-Aziz mapped out three different flooding scenarios below:

To be sure, the storm is still at least a week away. Depending on atmospheric conditions, it could menace a wide stretch of the US east coast. If it’s still a powerful category 3 or 4 storm when it hits – as projections suggest it would be – the US could be bracing for its second major natural disaster in two weeks.

5 Charts Showing Where Hurricane Irma Might Land

For anyone wondering why meteorologists can’t say for certain where Hurricane Irma – now a category 3 storm – might land in the US, Jonathan Erdman, a senior meteorologist at Weather.com, has an explanation. First, let’s look at the National Hurricane Center current forecast cone, a five-day forecast.

According to NHC statistics, the average error in a five-day forecast path of the center in 2016 was about 194 miles. While NHC track forecasts have improved over the years, this is still a sizable error at five days, roughly the distance between Miami and Cape Canaveral, or from midtown Manhattan to Martha"s Vineyard.

A basic tenet of numerical weather prediction is that small errors grow with time. If the five-day track error is already almost 200 miles, imagine what a 10-plus-day track error would be?

So, in the spirit of offering a more comprehensive assessment of where the hurricane might land, Erdman recommends looking at what’s called an ensemble model. Instead of using one set of parameters, economists use a range of initial conditions.

The ensemble forecast from the European Centre for Medium-Range Weather Forecasts can be seen below, in grey. The data are current as of Aug. 31 at 8 p.m. EDT. As Weather.com notes, readers can hardly see the US map below the mess of possible tracks, extending from south of Newfoundland to the Gulf of Mexico…

…And here’s another set of projections from NOAA.

Of course, forecasting the path of a hurricane with complete certainty is impossible. All meteorologists can say with some degree of accuracy is that the US East Coast and the Gulf of Mexico should be paying attention.

While it’s difficult to neatly sort a hurricane into a series of scenarios, meteorologists at Weather.com created illustrations showing what an east-coast landfall – as well as a near miss – might look like.

Ultimately, whether Irma hits the East Coast will depend on the Bermuda-Azores high, the primary steering wheel for Atlantic tropical cyclones.

“When this high is strong and expansive in west-to-east extent and/or there"s little or no southward plunge of the jet stream anywhere near the eastern U.S., an approaching hurricane would be steered westward into the Caribbean Sea, Gulf of Mexico or East Coast.”

While the path and precise landfall of the storm is still unclear, at least one metereologist has described Irma"s 180-mph winds as "the highest windspeed forecasts I"ve ever seen in my 10 yrs of Atlantic hurricane forecasting."

These are the highest windspeed forecasts I"ve ever seen in my 10 yrs of Atlantic hurricane forecasting. #Irma is another retiree candidate. pic.twitter.com/e6nMsp1myY

— Michael Ventrice (@MJVentrice) August 31, 2017

Meteorologists should have a clearer picture of what to expect in a few days. After seeing photos of the flooding in Texas, we imagine homeowners along the Atlantic seaboard, not to mention the Gulf of Mexico, will be nervously awaiting more news.

Irma Turning Into Monster Hurricane: "Highest Windspeed Forecasts I've Ever Seen"

Hurricane Irma continues to strengthen much faster than pretty much any computer model predicted as of yesterday or even this morning.  Per the National Hurricane Center"s (NHC) latest update, Irma is currently a Cat-3 storm with sustained winds of 115 mph but is expected to strengthen to a devastating Cat-5 with winds that could top out at 180 mph or more.  Here is the latest from the NHC as of 5PM EST:

Irma has become an impressive hurricane with intense eyewall convection surrounding a small eye.  Satellite estimates continue to rapidly rise, and the Dvorak classifications from both TAFB & SAB support an initial wind speed of 100 kt.  This is a remarkable 50-kt increase from yesterday at this time.

Irma continues moving west-northwestward, now at about 10 kt. There has been no change to the forecast philosophy, with the hurricane likely to turn westward and west-southwestward over the next few days due to a building ridge over the central Atlantic.  At long range, however, model guidance is not in good agreement on the strength of the ridge, resulting in some significant north-south differences in the global models.  I am inclined to stay on the southwestern side of the model guidance, given the rather consistent forecasts of the ECMWF and its ensemble.  In addition, the strongest members of the recent ensembles are on the southern side on the consensus, giving some confidence in that approach.

FORECAST POSITIONS AND MAX WINDS

INIT  31/2100Z 17.3N  34.8W  100 KT 115 MPH

12H  01/0600Z 17.8N  36.2W  105 KT 120 MPH

24H  01/1800Z 18.2N  38.3W  105 KT 120 MPH

36H  02/0600Z 18.3N  40.7W  105 KT 120 MPH

48H  02/1800Z 17.9N  42.9W  105 KT 120 MPH

72H  03/1800Z 16.8N  47.5W  110 KT 125 MPH

96H  04/1800Z 16.0N  52.0W  115 KT 130 MPH

120H  05/1800Z 16.5N  56.5W  120 KT 140 MPH

As of now, Irma remains in the far eastern Atlantic ocean and is moving west at roughly 11.5 mph.  Based on current projections, the storm will make its first landfall in the eastern Caribbean sometime toward the middle of next week.

Longer term computer models still vary widely but suggest that Irma will make landfall in the U.S. either in the Gulf of Mexico or Florida.  Meteorological Scientist Michael Ventrice of the Weather Channel is forecasting windspeeds of up to 180 mph, which he described as the "highest windspeed forecasts I"ve ever seen in my 10 yrs of Atlantic hurricane forecasting."

These are the highest windspeed forecasts I"ve ever seen in my 10 yrs of Atlantic hurricane forecasting. #Irma is another retiree candidate. pic.twitter.com/e6nMsp1myY

— Michael Ventrice (@MJVentrice) August 31, 2017

In a separate tweet, Ventrice had the following troubling comment: "Wow, a number of ECMWF EPS members show a maximum-sustained windspeed of 180+mph for #Irma, rivaling Hurricane #Allen (1980) for record wind"

The Weather Channel meteorologist also calculated the odds for a landfall along the eastern seaboard at 30%.

Up to a 30% chance via the 12Z Calibrated ECMWF EPS for a landfalling Major Hurricane somewhere along the eastern seaboard #Irma pic.twitter.com/nUmZkPGJpY

— Michael Ventrice (@MJVentrice) September 1, 2017

Meanwhile, the Weather Channel has the "most likely" path of Irma passing directly over Antigua, Puerto Rico and Domincan Republic toward the middle of next week.

pic.twitter.com/XTQtUur1PH Nuevo análisis del huracán #Irma por The Weather Channel

— Roberto F. Pardo A. (@robertofaridp) August 31, 2017

As Harvey Moves Inland, A New Hurricane Is Forming Over The Atlantic

Update: According to the NHS, Atlantic Tropical Storm Irma has formed, and could be a Hurricane by Friday. With top winds of 50 miles (80 kilometers) per hour, Irma formed 420 miles west of Cabo Verde moving west at 13 mph, the U.S. National Hurricane Center in an 11 a.m. N.Y. time advisory.

According to Jeff Masters, co-founder of Weather Underground, computer forecast models disagree on its ultimate track but a U.S. strike later in September cannot be ruled out.

Irma is the ninth named storm of the Atlantic hurricane season, which also produced Harvey that devastated southeastern Texas, including Houston, and disrupted energy facilities and supplies and destroyed crops. Irma could become a Category 1 hurricane on the five-step Saffir-Simpson scale by Friday and gradually get stronger through Monday.

If its current track holds, Irma would still be bearing down from the east on the Leeward and Windward Islands in the Caribbean Sea Monday

* * *

The National Hurricane Center (NHC) will be initiating advisories at 11 AM AST, as the new area of low pressure in the eastern Atlantic Ocean will develop into Tropical Storm Irma. Tropical Storm Irma will become the 9th storm of the 2017 Atlantic hurricane season as it moves towards the Gulf of Mexico region.

NHC will be initiating advisories at 11 AM AST on Tropical Storm Irma, located west of the Cabo Verde Islands.

— NHC Atlantic Ops (@NHC_Atlantic) August 30, 2017

Per Weather Channel,

In the near-term, future Irma will bring locally heavy rain and gusty winds to the Cabo Verde Islands through Wednesday.

South Florida Weather Management District (SFWMD) reports various pathways for Irma.

National Weather Service (NHS) reports Global Tropics Hazards and Benefits Outlook for the next 1-2 weeks. First week, Irma is labeled as a ‘tropical cyclone formation’  heading towards Caribbean Sea and the Gulf of Mexico. Second week, passing inland and over Central America.

"There is the potential to ramp up to a powerful hurricane in the coming days," according to AccuWeather Hurricane Expert Dan Kottlowski.

Irma will take about a week for the system to make its trek westward across the Atlantic Ocean. Meteorologists will likely be tracking this storm through the middle of September.

"All interests in the eastern Caribbean will need to monitor the progress of this evolving tropical cyclone, especially next week," Kottlowski said.

"It is way too soon to say with certainty where and if this system will impact the U.S."

Meanwhile, Texas and now southwestern Louisiana are still dealing with Tropical Storm Harvey. The weather disturbance has caused a great deal of destruction and cannot afford another storm such as Irma.

Conclusion

Luckily, Irma’s models via the major weather agencies provided above show current trajectories missing the devastated region. We all know in weather forecasting just like stock market forecasting models tend to be wrong – just ask Dennis Gartman.