Have you bought a shovel yet? Officials urge Seattleites to prepare for possible snow.

Mayor Jenny Durkan urged residents Thursday to make sure they have supplies on hand that may not be a given for Seattleites: snow shovels and salt.

“The bottom line is we don’t know what’s going to hit us,” Durkan said.

Seattle officials say they’re readying plows and salt as the forecast shows a possibility of snow in the coming days.

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The National Weather Service in Seattle predicts some snow this week in places like the Issaquah Highlands and Everett, but isn’t certain yet whether an Arctic front headed for the region will bring snow to Seattle early next week.

The area will see bitter cold next week, with temperatures in Seattle expected to drop Sunday night. The weather service is forecasting highs of around 30 degrees during the workweek, with temperatures as low as 18 degrees on Tuesday, which is expected to be the coldest day of the week. Other parts of Western Washington will see even colder temperatures.

Along with stocking up on supplies, check on your neighbors to see who may need help if the weather takes a turn, Durkan and Seattle Department of Transportation (SDOT) Director Sam Zimbabwe urged the public Thursday.

Record-breaking snow storms hit the region last February, disrupting school, traffic, garbage pickup and bus service. Overall, Seattle Times readers offered local officials relatively high marks for their response.

But for some, the storms proved deadly or isolating. At least four people in King County died of hypothermia-related causes, including a 59-year-old man who was believed to be homeless and was found at the Sodo light-rail station. Disability-rights advocates also highlighted stories of people trapped in their homes because of uncleared sidewalks.

Severe-weather shelters will open in King County Sunday night in preparation for freezing temperatures.

For clearing snow on city streets, Seattle uses “emerald” and “gold” designations to prioritize major routes for plowing. “Don’t expect your neighborhood will be plowed immediately,” Durkan said.

SDOT is responsible for some sidewalks and paths that are not immediately adjacent to homes and businesses, like overpasses and public stairways. Otherwise, adjacent property owners or residents are responsible for clearing sidewalks.

“If you see that snow, do your job [to clear it] and if you can’t, get people to help you,” Durkan said.

Residents who don’t clear their sidewalks may get warnings. Although city code allows for fines starting at $50 for failure the clear the sidewalk of snow and ice, an SDOT spokesman said the department will prioritize educating people over fines.

Members of the disability-rights group Rooted in Rights welcomed the new focus on sidewalk clearing. “Hopefully the rest of the city listens,” said Rooted in Rights producer Clark Matthews.

Program Director Anna Zivarts urged people to remember that clearing only a narrow path on the sidewalk may still not make it passable for someone using a wheelchair. Clear the full width of the sidewalk to make sure anyone can use it.

King County Metro has restocked its snow-chain supply and is asking riders to sign up for email or text alerts to be updated if snow affects bus service, said spokesman Jeff Switzer. Riders should also check MetroWinter.com for more information. Emergency alerts are also available at alert.seattle.gov and from ALERT King County.

When snow is severe enough, Metro downgrades service to about 65 routes known as the Emergency Snow Network. The agency has added several routes to the network, Switzer said, including part of Route 60 serving Beacon Hill, the 67 in North Seattle, part of the 106 in Rainier Beach and several DART routes, which operate mostly in suburban areas and allow people to request customized rides.

Under new county policy, fare enforcement will be suspended when the Emergency Snow Network is activated.

Switching from driving to taking transit during the snow could be complicated for some by light-rail service disruptions underway now as Sound Transit connects rails under construction to Bellevue. Trains are running less frequently than usual and riders have to switch trains at Pioneer Square Station to continue north or south.

Due to the construction, light rail won’t run through some stations on the weekends of Feb. 8-9 and March 14-15, with buses instead shuttling riders on the surface to stops between Capitol Hill and Sodo.

Snow response last February cost SDOT about $7 million, about half that in labor costs including overtime, according to SDOT. Equipment and related expenses cost about $2.4 million, and salt and de-icer cost about $1.2 million, according to SDOT.

Regional and state officials have also been preparing for snow, ordering thousands of tons of salt.

Seattle Times staff reporter Asia Fields contributed to this story. This story was updated to include newly available figures about the cost of SDOT’s response to last year’s storms.