1. Tropical storm force winds that could cause tree damage and power outages will continue to spread across New England tonight.

2. Heavy rainfall near the path of Isaias, through the Hudson River Valley, is likely to result in flash flooding, particularly through urban areas and the surrounding terrain of the Catskills, Adirondack and Green Mountain Ranges through Tuesday night. Scattered minor to moderate river flooding is likely across portions of the Mid-Atlantic. Quick-responding rivers in the Northeast will also be susceptible to minor and possible moderate river flooding.

3. The threat of tornadoes will spread into New England this afternoon and evening.

CHANGES WITH THIS ADVISORY:

The Tropical Storm Warning has been discontinued south of Manasquan Inlet, New Jersey, including all of the Chesapeake Bay, the Tidal Potomac River, and Delaware Bay. The Tropical Storm Warning has also been discontinued north of Stonington, Maine.

SUMMARY OF WATCHES AND WARNINGS IN EFFECT:

A Tropical Storm Warning is in effect for...
- Manasquan Inlet New Jersey to Stonington Maine
- Long Island and Long Island Sound
- Martha's Vineyard, Nantucket, and Block Island

A Tropical Storm Warning means that tropical storm conditions are expected somewhere within the warning area, in this case within the next 6 to 12 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 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...

Sandy Hook NJ to Martha's Vineyard MA including Long Island Sound, Block Island Sound, Narragansett Bay, Buzzards Bay, and Vineyard Sound...12 ft

WIND: Widespread tropicalstorm conditions are expected in the tropical storm warning area in eastern New York, Long Island, and southern New England, with wind gusts to hurricane force possible. These winds could cause significant tree damage and power outages.

Tropical storm conditions are expected to reach southern New England by late afternoon, and reach 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:

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. Southern Quebec: 1 to 3 inches.

Heavy rainfall near the path of Isaias, through the Hudson River Valley, is likely to result in flash flooding, particularly through urban areas and the surrounding terrain of the Catskills, Adirondack and Green Mountain Ranges through Tuesday night. Scattered minor to moderate river flooding is likely across portions of the MidAtlantic. Quickresponding rivers in the Northeast will also be susceptible to minor and possible moderate river flooding.

TORNADOES: A couple of tornadoes are possible across southern New England late this afternoon. A risk for tornadoes may continue and spread across parts of northern New England through this evening.

SURF: Swells generated by Isaias 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 PM EDT (2100 UTC), the center of Tropical Storm Isaias was located by NOAA Doppler weather radars and surface observations near latitude 42.7 North, longitude 74.2 West. Isaias is moving toward the northnortheast near 40 mph (65 km/h), and this general motion is expected through tonight. On the forecast track, the center of Isaias will continue to move farther inland over eastern New York and Vermont this afternoon and evening, and over southern Canada tonight.

Data from Doppler weather radars along with surface observations indicate that maximum sustained winds have decreased to near 65 mph (100 km/h) with higher gusts. Gradual weakening is expected this afternoon and evening, followed by a faster rate of weakening tonight. Isaias is forecast to become posttropical tonight or early Wednesday.

Tropicalstormforce winds extend outward up to 205 miles (335 km) from the center. During the past hour, a NOAA NOS observing site at Sandy Hook, New Jersey, reported a sustained wind 41 mph (67 km/h) and a gust to 50 mph (80 km/h). Wind gusts in excess of 50 mph (80 km/h) have also been reported at multiple sites in southeastern New York, Connecticut, Rhode Island, and Massachusetts during the past hour. The estimated minimum central pressure based on surface observations is 995 mb (29.39 inches).

NOAA Doppler radar data from Islip, New York (KOKX), indicated 70-kt winds just off the surface south of Long Island earlier this afternoon, along with buoy reports from New York Harbor Inlet (44065) that supported lowering the intensity to 55 kt, so that value is used for this advisory.

The motion remains north-northeastward or 020/35 kt. Isaias will continue moving north-northeastward through tonight, accompanied by a gradual decrease in forward speed. In 12 hours or, the cyclone is expected to interact with a larger extratropical over southeastern Canada and degenerate into a post-tropical cyclone near western Maine. By 24 hours, Isaias is expected to transition to an extratropical low, and dissipate or become absorbed by the aforementioned larger extratropical low. The new NHC track forecast is just an extension of the previous advisory, and lies very close to the tightly clustered consensus track models.

Isaias will continue to gradually spin down and lose its tropical characteristics. The precipitation has decreased in size and also has become more stratiform in appearance, which are indications that the cyclone is gradually weakening. This downward trend should continue until Isais becomes an extratropical low in 12-24 hours.

There also remains a risk of tornadoes across portions of New England this afternoon and evening