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Tropical Storm Isaias Timeline: What to expect from the storm in the tri-state area

Isaias timeline Tuesday
Tracking Tropical Storm Isaias
Posted at 9:14 PM, Aug 03, 2020
and last updated 2020-08-04 09:19:24-04

NEW YORK — Isaias made landfall Monday night in North Carolina as a hurricane, but was downgraded to a tropical storm before making its way to the tri-state region on Tuesday.

Tropical storm warnings, flash flood watches and even a tornado watch have been issued for the city and surrounding area as this storm is expected to pound the region with heavy rain and strong winds, and will cause coastal flooding.

The biggest threat from Isaias will be torrential downpours expected to create flash flooding, especially for areas west of the city.

Toward the middle part of the day, we will start to see the effects of the storm with the winds being on the increase.

Steadier downpours will develop during the afternoon and it will be the likeliest time for flash flooding to develop. The Storm Prediction Center has put the region on a "slight risk" for scattered severe storms. The circulation of Isaias could help spin off an isolated thunderstorm in any of the bands of heavy rain that passes through the region.

Most of the heavy rain should quickly end early in the evening and winds will gradually subside as we continue into the overnight hours on Tuesday.

NYC, Western Long Island and North New Jersey:
Heaviest rain: 11 a.m. to 2 p.m.
Strongest winds: Noon to 4 p.m.

Eastern Long Island:
Heaviest rain: 2 p.m. to 5 p.m.
Strongest winds: 2 p.m. to 5 p.m.

Hudson Valley, Connecticut:
Heaviest rain: 3 p.m. to 6 p.m.
Strongest winds: 3 p.m. to 6 p.m.

South New Jersey:
Heaviest rain: 9 a.m. to noon
Strongest winds: 10 a.m. to 1 p.m.

Expected rainfall totals, wind speeds, flooding and more:

Broadly speaking, expect 2 to 4 inches of rain from the city and points west. Some spots that may even get 5 or more inches of rain. East of the city, rainfall amounts will quickly drop off with an inch or less possible in some cases.

While areas west of the city will get heavy downpours, points east will be getting the strong winds. The winds may gust to over 50 mph at times. There are indications that some spots may even exceed 60 mph. The winds will continue through the early evening hours before it subsides as Isaias travels into New England. Power outages are likely as the strong winds will bring down tree limbs onto power lines.

Along the coast, watch for a storm surge that could reach 1 to 3 feet. Moderate coastal flooding is a possibility for Tuesday evening's high tide cycle. The tides are already running higher than normal, as a full moon occurred on Monday.

If there is some uncertainty with Isaias, it will be the location of where the heaviest rainfall occurs. The latest forecast models have indicated a westerly shift. That would bring the heavier downpours further inland and bring down rainfall amounts from the city and points east. This will ultimately depend on how Isaias tracks through the region on Tuesday