National Weather Service issues hurricane warning for Connecticut and Gov. Lamont declares a state of emergency in advance of Hurricane Henry. Up to 50% of Eversource customers may lose power.

The National Weather Service has issued a hurricane warning from New Haven to Rhode Island, as Hurricane Henri heads for a direct hit on Connecticut, bringing the likelihood of severe flooding, high winds and widespread power outages across the state.

“With the current forecasted track of Henri, we can expect heavy rainfall and high winds, with the potential for a significant amount of coastal flooding and urban flooding across Connecticut,” said Gov Ned Lamont, who will return Saturday morning to the state from his vacation home in Maine. “I will be declaring a state of emergency in advance of the storm making landfall, which will enable the state to take any actions necessary to respond and protect the people of the state.”

A storm surge warning is in effect from Greenwich to Cape Cod, with powerful ocean flooding potentially inundating shoreline communities.

Lamont said the state’s Emergency Operations Center will be fully activated by Saturday morning. “We’ll have the relevant state agencies there, as well as utility company representatives, to monitor and manage any issues that may arise.”

The governor is calling 200 Guardsmen and women to state active duty beginning on Saturday morning to prepare teams and specialized equipment in support of the state’s response. Lamont said he is asking President Biden for a pre-landfall emergency declaration to provide the state with federal assistance in anticipation of the impacts of the storm.

Eversource is warning of widespread power outages that could last up to 10 days.

“Henri has the potential for significant and lengthy outages. Customers should be prepared for multiday restoration, up to 5 to 10 days,’' said Eversource spokesman Mitch Gross.

Eversource President and CEO Joe Nolan said the company predicts between 30% and 49% of its customers will lose power as a result of the storm. The company has brought in thousands of extra workers to respond to expected power outages.

Tropical Storm Henri, currently located in the Atlantic Ocean off the coast of the Southeastern United States, is forecast to become a hurricane by Saturday and reach Connecticut by Sunday, causing significant rainfall and potential flooding.

If it makes landfall in Connecticut, it will be the first hurricane to do so since Hurricane Gloria in 1985.

“We only have so many threats of this magnitude that ever crop up during a year or even a decade,” said Bob Maxon, a meteorologist at NBC Connecticut. “People in their 20s and 30s have never experienced anything like the potential that’s there for Sunday and Monday.”

What can Connecticut expect this weekend?

Rain is expected to start early in the day Sunday, intensify Sunday afternoon and evening and then continue into Monday. The impact, Maxon said, could be similar to what Connecticut experienced with Superstorm Sandy and Hurricane Irene, which did not make landfall in the state but still caused extensive flooding and damage.

“When a tropical system sits, the rainfall can be epic, biblical,” Maxon said.

The National Hurricane Center on Friday morning issued a storm surge watch for the entire Connecticut coastline, plus much of Long Island, Rhode Island and Cape Cod. Additionally, the center issued a tropical storm watch for all of Connecticut’s southern counties.

“Heavy rainfall may lead to flash, urban and small stream flooding, along with the potential for widespread minor and isolated river flooding, over portions of Southern New England Sunday into Monday,” the National Hurricane Center said in an 11 a.m. advisory.

The storm is expected to make landfall along the border between Connecticut and Rhode Island.

Joe Furey, co-chief meteorologist at WNTH News 8, said the storm is highly unlikely to blow out to sea and that it could instead keep creeping further west.

“You plan for the worst, hope for the best, but the trend is not in our favor,” Furey said. “The more we look at it the worse it looks. Everyone’s got to get prepared. Everyone’s got to get the generators gassed up and do what you need to do, knowing you could be out of power for a week.”

Is the state ready?

Nolan said Friday that Eversource’s response would be “all hands on deck,” with more than 4,000 crews from across the country.

“You will see a massive presence of utility people in this state like you’ve never seen before,” Nolan said. “We’ll do everything we possibly can to get everyone back [in power] and get them back safely.”

The Connecticut Division of Emergency Management and Homeland Security tweeted Friday morning that it “is working with [its] partners to monitor & prepare for impacts from Tropical Storm Henri.” The agency recommended that residents in affected areas prepare and review emergency plans.

Max Reiss, a spokesperson for Gov. Ned Lamont, said the state is “gathering information” and will share details about a multi-agency response plan Friday afternoon.

All state campgrounds will close on Saturday at 4 p.m. through at least Monday afternoon, the DEEP said, and state parks and forests may also close for day use this weekend.

Michael Passero, mayor of New London, said the city has been testing emergency equipment, prepping an emergency shelter and attempting to track homeless people to ensure their safety during the storm. Passero said all residents are encouraged to shelter in place Sunday.

“Keep your phones charged, stock up on bottled water, make sure that you’re putting away anything that could become a flying projectile in heavy winds,” he said. “Most importantly, during the storm stay off the roads and shelter in place.”

What’s causing the extreme weather?

Connecticut has had an eventful summer of weather, with several heat waves, a wave of storms in mid-July and now a potential hurricane.

“June was third-hottest June in 116 years, July was the third-wettest July in 116 years, so you went from the heat to the wetness,” Furey said. “We just had flooding rains yesterday and now we’re going to bring Henri in.”

Maxon said the heavy rainfall in July, plus the storm Thursday, could exacerbate the threat posed by Tropical Storm Henri.

“You throw [the storm] in with the saturated soil because of the rainy July we had, the third-wettest July on record, we had substantial and significant flooding yesterday, and we’re going to try to throw four-to-six inches of rain into this situation?” Maxon said. “That can lead to a lot of freshwater flooding, power outages and tree damage.”

Experts say extreme weather events are likely to become more common in Connecticut due to the effects of climate change.

Alex Putterman can be reached at aputterman@courant.com.

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