1. There is the danger of life-threatening storm surge inundationalong portions of the immediate coastline and adjacent waterways ofthe North Carolina coast, including portions of Pamlico and Albemarle Sounds. Residents in these areas should follow advice given by local emergency officials.

2. Isaias is expected to bring widespread sustained tropical stormforce winds and wind gusts to hurricane force to the mid-Atlanticcoast, including portions of the Chesapeake Bay region, throughthis afternoon, which could cause tree damage and power outages.Tropical storm conditions are expected to spread across New Englandtonight.

3. Heavy rainfall along the East Coast, near the path of Isaias,will result in flash flooding, some of which may be significant inNorth Carolina through the Mid-Atlantic and Northeast throughtonight. Potentially life-threatening urban flooding is possible in D.C., Baltimore, and elsewhere along and just west of the I-95 corridor today. Widespread minor to moderate river flooding is likely across portions of the Carolinas and the Mid-Atlantic. Quick-responding rivers in Northeast will also be susceptible to minor river flooding.

4. Tornadoes have already occurred over portions of northeastern North Carolina and southeastern Virginia overnight. The threat of tornadoes will spread northward along the mid-Atlantic coast today and then across New England by tonight.

CHANGES WITH THIS ADVISORY:

All warnings have been discontinued for the coast of North Carolina south of Surf City.

The Storm Surge Watch south of Surf City has also been discontinued.

SUMMARY OF WATCHES AND WARNINGS IN EFFECT:

A Storm Surge Warning is in effect for...
- Pamlico and Albemarle Sounds, including the Neuse and Pamlico Rivers
- Ocracoke Inlet North Carolina to the North Carolina/Virginia border

A Storm Surge Watch is in effect for...
- Surf City to Ocracoke Inlet North Carolina

A Tropical Storm Warning is in effect for...
- North of Surf City North Carolina to Eastport Maine
- Pamlico and Albemarle Sounds
- Chesapeake Bay
- Tidal Potomac River
- Delaware Bay
- Long Island and Long Island Sound
- Martha's Vineyard, Nantucket, and Block Island

A Storm Surge Warning means there is a danger of lifethreatening inundation, from rising water moving inland from the coastline, in the indicated locations. For a depiction of areas at risk, please see the National Weather Service Storm Surge Watch/Warning Graphic at hurricanes.gov. This is a lifethreatening situation. Persons located within these areas should take all necessary actions to protect life and property from rising water and the potential for other dangerous conditions. Promptly follow evacuation and other instructions from local officials.

A Storm Surge Watch means there is a possibility of life threatening inundation, from rising water moving inland from the coastline.

A Tropical Storm Warning means that tropical storm conditions are expected somewhere within the warning area, generally within 36 hours.

For storm information specific to your area, including possible inland watches and warnings, please monitor products issued by your local National Weather Service forecast office.

Key messages for Isaias can be found in the Tropical Cyclone Discussion under AWIPS header MIATCDAT4, WMO header WTNT44 KNHC, and on the web at www.hurricanes.gov/text/MIATCDAT4.shtml.

STORM SURGE: The combination of a dangerous storm surge and the tide will cause normally dry areas near the coast to be flooded by rising waters moving inland from the shoreline. The water could reach the following heights above ground somewhere in the indicated areas if the peak surge occurs at the time of high tide...

Little River Inlet SC to Surf City NC...12 ft Surf City to Ocracoke Inlet NC...24 ft Ocracoke Inlet to the North Carolina/Virginia border including Pamlico Sound, Albemarle Sound, Neuse and Pamlico Rivers...35 ft

North of the North Carolina/Virginia border to Martha's Vineyard including the Chesapeake Bay, the Tidal Potomac River, Delaware Bay, Long Island Sound, Block Island Sound, Narragansett Bay, Buzzards Bay, and Vineyard Sound...13 ft

The deepest water will occur along the immediate coast in areas of onshore winds, where the surge will be accompanied by large waves. Surgerelated flooding depends on the relative timing of the surge and the tidal cycle, and can vary greatly over short distances. For information specific to your area, please see products issued by your local National Weather Service forecast office.

WIND: Widespread tropicalstorm conditions are expected in the tropical storm warning area from coastal North Carolina through the midAtlantic states, including portions of the Chesapeake Bay region today, with wind gusts to hurricane force possible. These winds could cause tree damage and power outages.

Tropical storm conditions are expected to reach southern New England this afternoon and northern New England tonight.

Galeforce winds are expected to spread into southeastern Quebec tonight and Wednesday. See products issued by Environment Canada for more information.

RAINFALL: The following rainfall accumulations are expected along and near the track of Isaias: Central and eastern North Carolina into the MidAtlantic: 3 to 6 inches, isolated maximum totals 8 inches. Eastern New York into Vermont: 2 to 4 inches, isolated maximum totals 6 inches. Western Connecticut, western Massachusetts, New Hampshire and western Maine: 1 to 3 inches. Heavy rainfall along the East Coast, near the path of Isaias, will result in flash and urban flooding, some of which may be significant in North Carolina through the MidAtlantic and Northeast through tonight. Potentially lifethreatening urban flooding is possible in D.C., Baltimore, and elsewhere along and just west of the I95 corridor today. Widespread minor to moderate river flooding is likely across portions of the Carolinas and the MidAtlantic. Quickresponding rivers in the Northeast will also be susceptible to minor river flooding.

TORNADOES: Tornadoes are most likely through midday from southeast Virginia to New Jersey. Tornadoes will remain possible this afternoon and evening from southeast New York across New England.

SURF: Swells generated by Isaias are affecting portions of the southeast coast of the United States and will spread northward along the MidAtlantic and Northeast coasts of the United States today. These swells are likely to cause lifethreatening surf and rip current conditions. Please consult products from your local weather office.

At 500 AM EDT (0900 UTC), the center of Tropical Storm Isaias was located over northeastern North Carolina near latitude 36.3 North, longitude 77.5 West. Isaias is moving toward the northnortheast near 28 mph (44 km/h), and this general motion accompanied by some additional increase in forward speed is expected through today. On the forecast track, the center of Isaias will to move into southeastern Virginia early this morning, near or along the coast of the midAtlantic states today, and across the northeastern United States into southern Canada tonight.

Maximum sustained winds are near 70 mph (110 km/h) with higher gusts. Only gradual weakening is anticipated while Isaias moves northnortheastward near the midAtlantic coast today. A faster rate of weakening is expected to begin tonight, and the system is forecast to become posttropical tonight or early Wednesday. Tropicalstormforce winds extend outward up to 140 miles (220 km) from the center. Sustained winds of 48 mph (78 km/h) and a gust to 63 mph (102 km/h) was recently reported at Duck, North Carolina. Sustained winds of 39 mph (63 km/h) and a gust to 56 mph (91 km/h) were also reported at Poquoson, Virginia.

The estimated minimum central pressure is 993 mb (29.33 inches).

Isaias made landfall near Ocean Isle Beach, North Carolina, a fewminutes after the previous advisory package was issued. Sincethat time, the center of Isaias has been moving quicklynorth-northeastward across eastern North Carolina. Now that theinner core of Isaias has moved inland, the peak surface winds havedecreased despite Doppler radar data still showing an area of75-85 kt winds aloft. The latest surface observations indicatedthat strong winds are occuring over the North Carolina Sounds andOuter Banks. Based on a blend of the available data, the initialwind speed is set at 60 kt for this advisory.

As the tropical storm moves northward near the Mid-Atlantic coast,interaction with a strong jet stream is likely to result in aslower-than-typical weakening rate. The global model guidanceindicates that Isaias is likely to produce widespreadtropical-storm conditions, with hurricane-force wind gusts possiblealong the mid-Atlantic coast through this afternoon. As a result,the gust factor at 12 h has been increased above the standard 20percent in the Forecast/Advisory (TCMAT4). Isaias is forecast toweaken more quickly tonight as it moves into eastern Canada andbecomes post-tropical. The post-tropical cyclone is forecast to beabsorbed by a larger extratropical low in 2-3 days, if not sooner.

Isaias is moving north-northeastward or 020/24 kt. The cyclone isforecast to continue accelerating north-northeastward today as itis embedded in strong south-southwesterly flow ahead of a deep-layertrough over the Great Lakes region. After 24 h, the post-tropicalcyclone is expected to decelerate before it is absorbed by theextratropical low. The updated NHC track forecast is near thecenter of the tightly clustered guidance envelope.

In addition to the storm surge and wind threats, Isaias is expectedto produce heavy rainfall along and just west of the I-95 corridor today, and the Weather Prediction Center has placed a portion of this area in a high risk for life-threatening flash flooding. There is also a risk of tornadoes from southeast Virginia to New Jersey through midday. The risk of tornadoes will spread northward into southeastern New York this afternoon and across New England bytonight.