An Arctic blast of frigid air is arriving and people across the northern US and northeastern US should prepare for its impacts.

The jet stream will allow bitterly cold air from the region near the North Pole to ooze down over the US, bringing temperatures to well-below normal for many.

The cold air will also push through windy conditions; winds may exceed 40mph in parts of Pennsylvania, New York, Delaware, Maryland, and New Jersey Thursday night. When the low temperatures and strong winds are combined, dangerously low wind chill factors will also become likely.

A disturbance following the surge of cold air may also trigger snow showers from Washington, DC to Boston, MA late Wednesday night to Thursday.

This arriving cold air will also create weather problems for many around the I-95 cities at the end of this week and the start of the weekend. With cold air firmly in place, precipitation associated with a new area of low pressure will push into the Mid Atlantic and Northeast, producing plain snow.

But as milder air works its way in above the surface, the snow will change to rain. During that transition period, there could be a prolonged period of freezing rain. With accumulating ice possible for some, travel may become extra-hazardous early Saturday during that icy transition period.

Here’s our thoughts to precipitation types and timing:

Washington, DC: Snow arrives during Friday late afternoon hours; wintry mix of freezing rain and sleet by Saturday morning, with plain rain likely after lunchtime.
Philadelphia, PA: Snow arrives late Friday; icy mix before sunrise; rain likely after sunrise.
New York, NY: Snow arrives after midnight on Friday night; icy mix begins around sunrise; plain rain likely by lunchtime.
Boston, MA: Snow arrives around midnight Friday night; snow mixing with sleet and rain Saturday mid-morning; precipitation changing back to snow during Saturday afternoon, changing back to rain Saturday evening. Plain rain likely after dinner.