National Hurricane Center Update – Irene About to Re-emerge Over Atlantic Waters, August 27, 2011 (Update 5 PM EDT)

Miami, Florida—(ENEWSPF)—August 27, 2011.

Summary of 5 PM EDT (210 UTC) Information

The National Hurricane Center reports that Hurricane Irene is currently located 36.2 N (76.0 W), about 50 miles (80 km) SSE of Norfolk, Virginia, about 350 miles (545 km  SSW of New York City.  Maximum sustained winds are 80 mph (130 km/h). Present movement is NNE or 15 degrees at 13 mph (20 km/h). Minimum central pressure is 950 mb (28.05 inches).

Watches and Warnings

Changes in Watches and Warnings With This Advisory

The Hurricane Warning has been discontinued south of Cape Fear, North Carolina.

Summary of Watches and Warnings in Effect

A Hurricane Warning is in Effect For

  • Cape Fear, North Carolina northward to Sagamore Beach, Massachusetts, including the Pamlico, Albemarle, and Currituck Sounds, Delaware Bay, Chesapeake Bay south of Drum Point, New York City, Long Island, Long Island Sound, Coastal Connecticut, and Rhode Island, Block Island, Martha’s Vineyard and Nantucket.

A Tropical Storm Warning is in Effect For

  • Chesapeake Bay from Drum Point northward and the Tidal Potomac  
  • North of Sagamore Beach to Eastport, Maine  
  • United States/Canada Border northeastward to Fort Lawrence including Grand Manan  
  • South Coast of Nova Scotia from Fort Lawrence to Porters Lake

Interests elsewhere in Eastern Canada should monitor the progress of Irene.

For storm information specific to your area in the United States, including possible inland watches and warnings, please monitor products issued by your Local National Weather Service Forecast Office.

For storm information specific to your area outside the United States, please monitor products issued by your National Meteorological Service.

Discussion and 48-hour Outlook

At 500 PM EDT (21:00 UTC), the center of Hurricane I was located near latitude 35.2 north, longitude 76.0 west. Irene is moving toward the north northeast near 13 mph (20 km/h) and this motion accompanied by a faster forward speed is expected during the next day or so.  On the forecast track, the center of Irene will move near or over the Mid-Atlantic coast tonight, and move over southern New England on Sunday. Irene is forecast to move into Eastern Canada Sunday night.

Maximum sustained winds are near 80 mph (130 km/h) with higher gusts. Irene is forecast to remain a hurricane as it moves near or over the Mid-Atlantic Coast and approaches New England. The hurricane is forecast to weaken after landfall and become a post-tropical cyclone Sunday night or early Monday.

Irene is a large tropical cyclone. Hurricane-force winds extend outward up to 85 miles (140 km) from the center, and tropical-storm force winds extend outward up to 290 miles (465 km).

A National Ocean Service observing site at Oregon Inlet, North Carolina recently reported a sustained wind of 59 mph, with a gust of 81 mph. A sustained wind of 58 mph with a gust to 74 mph was recently measured at Manteo, North Carolina.

The latest minimum central pressure reported by an Air Force Reserve hurricane Hunter Aircraft was 950 mb (28.05 inches).

Hazards Affecting Land

Tropical-storm-force winds will spread northward along the Mid-Atlantic Coast this evening with hurricane conditions expected tonight. Tropical Storm conditions are expected to reach southern New England late this evening with hurricane conditions expected by Sunday morning. Winds affecting the upper floors of high-rise buildings will be significantly stronger than those near ground-level.

An extremely dangerous storm tide will raise water levels by as much as 5 to 9 feet above ground level in the hurricane warning area in North Carolina, including the Albemarle and Pamlico Sounds. Storm surge will raise water levels by as much as 4 to 8 feet above ground level within the hurricane warning area from the North Carolina/Virginia Border northward to Cape Cod including southern portions of the Chesapeake Bay and its Tributaries. Near the coast, the surge will be accompanied by large, destructive, and life-threatening waves. Higher than normal astronomical tides are occurring this weekend. Coastal and river flooding will be highest in areas where the peak surge occurs around the time of high tide. Storm tide and surge values are very location-specific, and users are urged to consult products issued by their Local National Weather Service Offices.

Irene is expected to produce rainfall accumulations of 6 to 12 inches, with isolated maximum amounts of 20 inches, from eastern North Carolina northward through the Mid-Atlantic States into eastern New York and interior New England.  These rains, combined with heavy rains over the past few weeks, could cause widespread flooding, life-threatening flash floods, and significant uprooting of trees due to rain-softened grounds.

Large swells generated by Irene are affecting much of the East Coast of the United States.  These swells will cause life-threatening surf and rip current conditions.

Isolated tornadoes are possible along the coast of Maryland, Delaware, and New Jersey through tonight.

Surface Wind Field

Click image to zoom in [Image of initial wind radii]
About this product:

This graphic shows the areas potentially being affected by the sustained winds of tropical storm force (in orange) and hurricane force (in red). The display is based on the wind radii contained in the latest Forecast/Advisory (indicated at the top of the figure). Users are reminded that the Forecast/Advisory wind radii represent the maximum possible extent of a given wind speed within particular quadrants around the tropical cyclone. As a result, not all locations falling within the orange or red shaded areas will be experiencing sustained tropical storm or hurricane force winds, respectively.

In addition to the wind field, this graphic shows an approximate representation of coastal areas under a hurricane warning (red), hurricane watch (pink), tropical storm warning (blue) and tropical storm watch (yellow). The white dot indicates the current position of the center of the tropical cyclone, and the dashed line shows the history of the center of the tropical cyclone. 

source: nhc.noaa.gov