A second snowfall this December swept across the Washington, D.C., metropolitan area early Sunday as an Arctic air mass delivered wintry precipitation and ushered in bitterly cold conditions.

Snow fell mostly before dawn, coating grass, roads and vehicles and creating slick side streets, though major thoroughfares remained largely passable without major disruptions.

Official weather observations at Reagan National Airport recorded around four-tenths of an inch of snow, adding to earlier accumulations from the first December event to bring the month’s total close to but still below the long-term average for December.

Snow amounts increased outside the core of the capital, with northern suburbs and counties to the north and northeast receiving higher totals.

In parts of northern Montgomery and Frederick counties, between two and five inches were reported, and some areas experienced thunder during the early-morning precipitation.

The light coating in the city itself makes this the first season since two thousand thirteen that Washington has recorded two distinct accumulating snow events this early in December.

Following the snowfall, temperatures plunged sharply as Arctic air settled in.

Wind chills were expected to dip toward zero degrees Sunday night and Monday morning, with sustained cold through the start of the workweek.

Forecasters warned that lingering slush and moisture would freeze, making secondary roads and sidewalks hazardous.

A gradual warming trend later in the week is forecast to boost daytime highs into the forties and fifties, although any remaining snow will melt before the holiday period.

This second December snow reinforces an active but modest snowy pattern for the region, where overall snowfall totals so far remain below what is typical for the season, and signals the transition to deeper winter conditions as cold air dominates the mid-Atlantic outlook.