Avian Flu Diary: Irene Targets Caribbean As Florida Waits

# 5767

Tropical Storm Irene, the 9th named storm of the 2011 Atlantic Tropical season, formed several hundred miles east of the Lesser Antilles late yesterday and is now lashing the Northern Leeward Islands with squalls and heavy rains.

It’s forecast path puts Puerto Rico, the island of Hispaniola, and Cuba under the gun over the next 96 hours, and most models have it posing a threat to South Florida five days from now.

The solid white area depicts the track forecast uncertainty for days 1-3 of the forecast, while the stippled area depicts the uncertainty on days 4-5.

Forecasts can change, and the cone of uncertainty is hundreds of miles wide 5 days out. Still, Floridians need to be making plans now for how they will deal with Irene should she come our way.

For the beleaguered residents of Haiti and the Dominican Republic, this will be the second tropical system to visit in less than a month. You’ll recall that a disheveled T.S. Emily dropped more than 20 inches of rain on parts of that island earlier this month, causing heavy flooding and several fatalities.

Conditions are somewhat better now for storm intensification, and Irene is forecast to reach hurricane strength before crossing the coastline of Hispaniola . . . either late Monday or early Tuesday.

The mountainous terrain of Hispaniola and Cuba are both famous for taking the punch out of tropical systems, and so Irene’s strength after passing these natural barriers is likely to be somewhat diminished.

How much, and how well can it recover once back over the warm waters of the Florida straits, is the question on a lot of Floridian’s minds right now.

The 5am discussion from the National Hurricane Center suggests that Irene will likely regain hurricane strength rapidly after clearing the islands of the Caribbean.

THE UPPER-LEVEL ENVIRONMENT IS EXPECTED TO BE QUITE FAVORABLE FOR STRENGTHENING THROUGHOUT THE FORECAST PERIOD AS A RESULT OF LOW SHEAR AND A MID-OCEANIC TROUGH TO THE EAST ACTING AS A MASS SINK
FOR THE OUTFLOW IN THE EASTERN SEMICIRCLE.

HOWEVER...THE INTENSITY FORECAST IS HEAVILY DEPENDENT ON HOW MUCH INTERACTION IRENE HAS WITH THE MOUNTAINOUS TERRAIN OF HISPANIOLA AND WHAT THE INNER CORE OF THE CYCLONE BECOMES AFTER IT EMERGES OFF THE NORTHEAST COAST OF CUBA IN ABOUT 4 DAYS.

ONCE OVER THE FLORIDA STRAITS...HOWEVER... IRENE WILL HAVE AT LEAST 24 HOURS OVER SOME OF THE WARMEST WATER IN THE ATLANTIC TO TAP INTO. THE OFFICIAL FORECAST REMAINS ON THE CONSERVATIVE SIDE DUE TO LAND EFFECTS AND IS CLOSE TO A BLEND OF SHIPS AND LGEM STATISTICAL INTENSITY MODELS.

FORECAST POSITIONS AND MAX WINDS

INIT 21/0900Z 16.4N 61.3W   45 KT 50 MPH
12H 21/1800Z 17.0N 63.7W   50 KT 60 MPH
24H 22/0600Z 17.5N 66.7W   60 KT 70 MPH
36H 22/1800Z 18.0N 69.2W   70 KT 80 MPH
48H 23/0600Z 18.6N 71.5W   50 KT 60 MPH ... INLAND
72H 24/0600Z 20.3N 75.3W   50 KT 60 MPH... INLAND
96H 25/0600Z 22.8N 78.2W   60 KT 70 MPH... OVER WATER
120H 26/0600Z 26.1N 80.7W   75 KT 85   MPH ... INLAND

With the exception of the UKMET and GFDL models, most of the computer runs are in close agreement as to the future path of Irene.

A Hurricane watch has been issued for Puerto Rico and surrounding islands, and it seems likely that Hispaniola will be dealing with a strong tropical storm or minimal hurricane in less than 48 hours where flooding and mudslides are always a major concern.

There also remain tens thousands of people who still live in scores of flimsy tent-and-tarp settlements that sprang up after Haiti’s 7.0 Earthquake in early 2010.

For Haiti, and to a lesser extent the Dominican Republic, heavy rains may further exacerbate their recent Cholera outbreaks, and could also help increase the number of mosquitoes that carry Dengue fever.

Other Interests in the Caribbean, and in the Southern United States, need to keep track of this storm’s progress as well. As always, the National Hurricane Center is your best source of information.