Tropical Storm Isaias Wreaks Havoc

646 

WTNT34 KNHC 041759

TCPAT4

BULLETIN

Tropical Storm Isaias Intermediate Advisory Number 30A

NWS National Hurricane Center Miami FL       AL092020

200 PM EDT Tue Aug 04 2020

...ISAIAS RACING NORTH-NORTHEASTWARD ACROSS EASTERN PENNSYLVANIA 

INTO SOUTHEASTERN NEW YORK...

...STRONG GUSTY WINDS...HEAVY RAINFALL...AND THE THREAT OF 

TORNADOES WILL SPREAD NORTHWARD INTO SOUTHERN NEW ENGLAND...

SUMMARY OF 200 PM EDT...1800 UTC...INFORMATION

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LOCATION...40.9N 75.1W

ABOUT 65 MI...105 KM w OF NEW YORK CITY

MAXIMUM SUSTAINED WINDS...65 MPH...100 KM/H

PRESENT MOVEMENT...NNE OR 20 DEGREES AT 40 MPH...65 KM/H

MINIMUM CENTRAL PRESSURE...994 MB...29.35 INCHES

WATCHES AND WARNINGS

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CHANGES WITH THIS ADVISORY:

The Tropical Storm Warning has been discontinued south of 

Chincoteague, Virginia, and south of Smith Point in the Chesapeake 

Bay.

SUMMARY OF WATCHES AND WARNINGS IN EFFECT:

A Tropical Storm Warning is in effect for...

* North of Chincoteague Virginia to Eastport Maine

* Chesapeake Bay north of Smith Point

* Tidal Potomac River

* Delaware Bay

* 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 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 200 PM EDT (1800 UTC), the center of Tropical Storm Isaias was

located by NOAA Doppler weather radars and surface observations near

latitude 40.9 North, longitude 75.1 West. Isaias is moving toward

the north-northeast near 40 mph (65 km/h), and this general motion

accompanied by some increase in forward speed is expected through

tonight. On the forecast track, the center of Isaias will continue

to move near or along the coast of the mid-Atlantic states today,

and move across the northeastern United States into 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. Only slow weakening is expected this 

afternoon, 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 140 miles (220 km)

from the center. The New York Harbor Entrance buoy (44065) recently 

reported a sustained wind of 56 mph (91 km/h) and a gust to 72 mph 

(117 km/h).

The estimated minimum central pressure based on surface

observations is 994 mb (29.35 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.

WIND:  Widespread tropical-storm conditions are expected in the

tropical storm warning area in the mid-Atlantic states and 

southern New England, including portions of the Chesapeake Bay 

region today, 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 this afternoon and 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:

Central and Northern Mid-Atlantic: Additional 2 to 4 inches,

isolated maximum storm totals of 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 the mid-Atlantic and Northeast through tonight. Potentially

life-threatening urban flooding remains possible Philadelphia, and

elsewhere along and just west of the I-95 corridor today. 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 river flooding.

TORNADOES:  A few tornadoes are possible across northern New Jersey

and southeastern New York, through southern New England, by late

afternoon.  A risk for tornadoes may continue across 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.

NEXT ADVISORY

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Next complete advisory at 500 PM EDT.

$$

Forecaster Stewart/Roberts