Lowland Snow Likely As Arctic Front Settles In Washington

SEATTLE, WA — Temperatures are expected to take a nosedive Sunday, bringing a hard freeze to Western Washington that will carry on through the week. According to the National Weather Service, cold air will begin to filter into the lowlands Sunday afternoon into Sunday night, turning precipitation from rain to snow for many, as snow levels potentially dip down to sea level.

LATEST: Lowland Snow, Frigid Temperatures Arrive Sunday Night

NWS Seattle has issued a Winter Storm Watch for much of the lowlands, including the Seattle metro area, effective through Sunday evening.

Forecasters said two periods will offer the best chance for lowland snow this week: Sunday night into Monday morning and Wednesday afternoon into Thursday. On Sunday, accumulation is expected to be heaviest in northern towns, but totals elsewhere could get a boost if a convergence zone develops. Snowfall accumulations between 1 and 4 inches are possible throughout Western Washington.

What is a convergence zone? The National Weather Service explains:

"A Puget Sound Convergence Zone (PSCZ) forms when strong westerly winds flow around the Olympic Peninsula and converge over Puget Sound. It generally forms north of Seattle, and may move southward to as far as Boeing Field or SeaTac Airport. A PSCZ can cause a narrow band of convective precipitation along it, which can include rain showers, thunderstorms, or snowfall."

On Wednesday, the heaviest snow is expected in the South Sound, and totals could range between 1 and 6 inches.

NWS Seattle said there was increasing confidence of a dry streak between Tuesday and Wednesday morning.

With or without the snow, the temperature outlook for the region shows frigid conditions through the week ahead. Lows around Seattle and Olympia could hit the teens by Tuesday, and Bellingham may see single digits at night between Monday and Wednesday.

Early estimates show afternoon highs in Seattle in the low 30s or high 20s throughout the week.

NWS meteorologists said predictions regarding precipitation amounts and the exact timing of any snowfall in the week ahead are still uncertain. More updates on the weather outlook will be released as conditions evolve.