Gov. Phil Murphy said Friday he is declaring a state of emergency across New Jersey, effective noon Saturday, as a winter storm is expected to wallop the state.

Murphy also announced a travel restriction barring tractor trailers, car-pulled trailers — anything attached to your car that gives you more than two axles — recreational vehicles, and motorcycles on roads north of Interstate 95. But that does not include the New Jersey Turnpike and Garden State Parkway.

“If there is ever a weekend to stay in and binge-watch something, this may be it,” Murphy said during a late-afternoon news conference at the State Police’s Regional Operations Intelligence Center in West Trenton.

Murphy said this is a “really challenging system” that could drop up to a foot of snow in parts of North Jersey.

But he said the “bigger culprit” will be the potential for ice as the temperature drops Sunday, causing slick, dangerous roads and possible widespread power outages.

A governor’s state of emergency declaration typically comes with stern warnings for people to stay off the roads, although law enforcement officers don’t have the authority to ticket drivers.

But the order does empower first responders to close roads, evacuate homes, and commandeer equipment or other resources to protect public safety.

Plus, after a high-impact storm, state officials seek financial assistance from the federal government to make repairs, and the emergency declaration is a required step in that process.

The state of emergency Murphy announced Friday covers all 21 of the state’s counties.

This storm comes just hours after after a lighter storm dropped caused delayed openings for some schools and state offices Friday morning. But state officials are urging residents not to be fooled into thinking the second storm will be as timid.

The National Weather Service has issued a winter storm warning for Hunterdon, Morris, Somerset, Sussex, and Warren counties from Saturday afternoon to Sunday evening.

The service has also declared a winter storm watch for Bergen, Essex, Hudson, Passaic and union counties from noon Saturday until 6 p.m. Sunday.

Forecasters are still unclear where the snow will mix with sleet and rain in the central part of the state. Conditions in South Jersey are expected to be more mild.

Murphy said the state is coordinating with regional transportation agencies, and the State Police is preparing its emergency operations center.

State Transportation Commissioner Diane Gutierrez-Scaccetti said New Jersey Transit is expected to run on its normal weekend schedule, but bus service could change depending on how the storm plays out.

State officials urged residents not to travel during the storm, both to remain safe and not stymie plows and emergency vehicles.

“If you do have to go out, be safe, be patient, be prepared,” State Police Superintendent Col. Patrick Callahan said.

Callahan said those that do go out should carry emergency items like a cell phone, charger, a bottle of water, and a blanket.

Murphy said it’s a blessing that the storm is happening on a weekend, followed by a state holiday, Martin Luther King Day, on Monday.

“Our aim is to have New Jersey fully ready for the work week,” the governor said.

State officials said crews have already begun brining roads and plows will be deployed early Saturday.

Murphy joked at an earlier news conference Friday in Woodbridge that he’s OK with the state over-preparing after the November snowstorm that unexpectedly crippled the state — and led to residents lambasting the rookie governor for not being better prepped.

“I’m going to be the chairman of the over-prepare club,” Murphy said.

Monitor the social media accounts for the Office of Emergency Management and the N.J. State Police for updates:

NJOEM on Facebook: www.facebook.com/READYNEWJERSEY

NJOEM on Twitter: www.twitter.com/ReadyNJ

NJ State Police on Facebook: www.facebook.com/NewJerseyStatePolice

NJ State Police on Twitter: www.twitter.com/NJSP

You may also sign up for text and email alerts:

NIXLE - www.nixle.com.

NJ Alert - www.njalert.gov.

NJ Advance Media staff writers Jeff Goldman, Kelly Heyboer, and Susan K. Livio contributed to this report.

Brent Johnson may be reached at bjohnson@njadvancemedia.com Follow him on Twitter @johnsb01

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