Please see below notice from Roadrunner:

Dear Valued Customer,

A winter storm will spread heavy snow across the Central Rockies through Friday, with snow expanding into the Southern Rockies today.

At Roadrunner, safety is always our #1 priority.

Please be advised that linehaul, pickups, and deliveries in Denver may be impacted causing delays. We will provide additional updates as we receive.

To track your shipments, click here or reach out to your Roadrunner representative.