BULLETIN
Tropical Storm Isaias Advisory Number 31…Corrected
NWS National Hurricane Center Miami FL AL092020
500 PM EDT Tue Aug 04 2020
Corrected Watches and Warnings summary.
…ISAIAS RACING NORTH-NORTHEASTWARD ACROSS EASTERN NEW YORK…
…STRONG GUSTY WINDS…HEAVY RAINFALL…AND THE THREAT OF
TORNADOES WILL SPREAD NORTHWARD ACROSS SOUTHERN AND CENTRAL NEW
ENGLAND…
SUMMARY OF 500 PM EDT…2100 UTC…INFORMATION
———————————————-
LOCATION…42.7N 74.2W
ABOUT 20 MI…35 KM W OF ALBANY NEW YORK
MAXIMUM SUSTAINED WINDS…65 MPH…100 KM/H
PRESENT MOVEMENT…NNE OR 20 DEGREES AT 40 MPH…65 KM/H
MINIMUM CENTRAL PRESSURE…995 MB…29.39 INCHES
WATCHES AND WARNINGS
——————–
CHANGES WITH THIS ADVISORY:
The Tropical Storm Warning has been discontinued south of
Sandy Point, 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…
* Sandy Point 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.
DISCUSSION AND OUTLOOK
———————-
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 north-northeast 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 post-tropical tonight or early
Wednesday.
Tropical-storm-force 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).
HAZARDS AFFECTING LAND
———————-
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…1-2 ft
WIND: Widespread tropical-storm 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.
Gale-force 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
Mid-Atlantic. Quick-responding 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
mid-Atlantic and Northeast coasts of the United States today. These
swells are likely to cause life-threatening surf and rip current
conditions. Please consult products from your local weather office.
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