Soaking Tropical Rains Mean End to Lovely Weather for East Coast

  • Three systems will bring flowing water to the U.S. East Coast
  • Rains will help ease drought that holds East in its grip

The bill is about to arrive for last week’s run of sunshine and mild temperatures along the northern East Coast.

Or, to put it another way, Mars won’t be the only place that has flowing water. Soon, it will be in New York, New England and much of the mid-Atlantic.

Three tropical weather systems will ensure a big chunk of the seaboard is awash in rain through the heart of the week, and then there’s a chance for a soaking at week’s end.

“It’s certainly going to be wet,” said Patrick Burke, a senior branch forecaster at the U.S. Weather Prediction Center in College Park, Maryland. “There are a lot of things that are converging to make it a wet week, especially late Tuesday into Wednesday night.”

Atlantic Storms

National Hurricane Center map shows potential tropical storm activity in the Atlantic as of 2 p.m. Sept. 28, 2015

High-level moisture from Tropical Storm Marty in the eastern Pacific Ocean is streaming northeast across the Gulf of Mexico. There, it’s joining with a disorganized patch of showers and thunderstorms that the National Hurricane Center has been watching for the past few days.

Storm Growth

The Miami-based center thought there was a chance the Gulf cluster could grow into an Atlantic tropical system. However, the odds of that happening have been falling.

The moisture from these two systems will merge and get dragged north by a dip in the jet stream. In the meantime, Tropical Storm Joaquin will add to the mix. All of this will ensure that New York’s week will be as cloudy and rainy as last week was sunny and dry.

On Tuesday, the National Weather Service posted flash flood watches from Maine to North Carolina. The prediction center called for as much as 5 inches (13 centimeters) of rain to fall across parts of northern New England through Thursday with more than 3 inches from Maine to Pennsylvania.

Joaquin could bring another round of heavy rain from New York into New England through the weekend, said Rob Carolan, a meteorologist with Hometown Forecast Services Inc. in Nashua, New Hampshire.

NYC Outlook

This could spell trouble for New York and its surrounding metropolitan area.

“All those rivers that go through urbanized areas,” Carolan said, assessing the flood risk to northern New Jersey and the lower Hudson River Valley. “That is a big concern.”

Even if Joaquin doesn’t ruin the weekend, another low-pressure system might develop off the East Coast later this week, bringing more rain, Burke said.

Rain is what the region needs. All of Connecticut is either abnormally dry or in drought, according to the U.S. Drought Monitor in Lincoln, Nebraska. Well over 85 percent of New Jersey, Massachusetts and Rhode Island are in the same shape, and about 63 percent of New York is parched. Drought or dry conditions touch each of the 48 contiguous states.

For reversing the drought, the rain is “good news,” said Thomas Downs, a meteorologist with WeatherBell Analytics LLC in New York.

The speed of the rain could bring about flash-flooding, Burke warned. But the dryness in the area will probably ensure it won’t be widespread because rivers, streams and ponds have room to absorb the deluge.

So, when you are dodging cabs under that umbrella this week, musing about the news that NASA found evidence of liquid water on Mars, remember the rain is for a larger good.

“You knew we had to pay for all of this beautiful weather at some point,” said Todd Crawford, principal scientist at WSI in Andover, Massachusetts.

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