Winter Weather — Copper River Basin, Alaska

2023-10-12 to 2023-10-13 · Copper River Basin, Alaska

Event narrative

The Alaska Department of Transportation reported at 4:50 AKST that up to 11 inches of snow had fallen overnight along portions of the Edgerton Highway near Kenny Lake.

Wider weather episode

A low pressure trough lifting north from the Gulf approached the Copper River Basin on the evening of 10/12 as a shield of precipitation spread north ahead of the trough axis from the Gulf coast into the southern Copper River Basin. Numerical models were slow to catch on to the amount of cold air holding on in place over the basin, and many solutions depicted a quick transition from snow to rain shortly after precipitation onset as warmer air began to filter in with southeast winds ahead of the approaching trough. Instead, colder air than expected held on away from the coastline for most of the night of 10/12, lasting into the early morning hours of 10/13. Up to 11 inches of new snowfall was reported along parts of the Edgerton Highway near Kenny Lake by the early morning of 10/13.

Source: NOAA Storm Events Database, event_id 1134986. Narrative written by the NWS forecast office that issued the report.