3 Reasons Tropical Storm Isaias Was So Damaging in the Northeast

Here's a look at what happened.

1. Fast Track Northward

Isaias' forward speed acceleration is one reason the storm was so damaging all the way through the Northeast.

The storm was moving north-northeast at over 30 mph as it tracked near the East Coast. That allowed less time for Isaias to weaken as it moved farther inland.

Isaias' fast movement was propelled by an unusually strong southward plunge of the jet stream over the Midwest and interior Northeast. A computer model analysis showed the jet stream's strength over the Northeast was roughly two times the average for this time of year. Therefore, it's a type of weather pattern more common as we head closer to fall instead of early August.

The Northeast was also in the right front quadrant of Isaias' wind field. The storm's wind speeds in this area are enhanced since air is moving in the same general direction of the storm's movement.

2. Jet Stream Interaction Gives a Boost

Strong jet stream winds can help intensify coastal storms like nor'easters in winter. It's likely Isaias received a similar boost of energy as it began its transition into a non-tropical low-pressure system over the Northeast, and that meant it weakened at a slower pace than usual.

"Interaction with a strong jet stream suggests that Isaias should weaken more slowly than normal as it moves through the eastern United States, and this should produce very strong wind gusts along the mid-Atlantic coast tomorrow," the National Hurricane Center said in a forecast discussion Monday.

3. Dense Population Struck

Isaias was so damaging because it took a near-perfect track up the densely populated Interstate 95 corridor. That meant many trees and power lines were in its path of strong winds.

The track just inland from the East Coast also caused Isaias' strongest winds to blow from off the ocean into areas near and inland from the coast. Winds coming from off the ocean as opposed to land areas encounter less friction as they funnel into the coastline, allowing them to remain stronger.

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