Traffic backed up in the snowy weather outside the Department of Public Safety after a collision Thursday. /Credit: Zac Schasteen, UDPS

Update, 6 p.m. Thursday: A blizzard warning is in effect for the Eastern Aleutians until tomorrow, and a Category 1 travel advisory remains in place in Unalaska.

The winter weather is making for some treacherous driving conditions in town. A two-vehicle collision took place on the roadway below the Department of Public Safety this afternoon. Public Safety couldn't release any further details on that crash on Thursday.

Public Safety is authorizing the use of tire chains for tractor-trailers, and they say drivers must turn their headlights on.

They says blowing snow and snow accumulation are causing intermittent whiteout conditions and slippery roads.

The blizzard warning lasts through Friday at 3 p.m.

Update, 10 a.m. Thursday: The Category 1 travel advisory remains in effect today. The Department of Public Safety says they'll renew it this afternoon unless conditions change.

Update, 6 p.m. Wednesday: A Category 1 travel advisory is in effect due to treacherous winter weather in Unalaska.

The Department of Public Safety issued the advisory Wednesday around 5:45 p.m. They say blowing snow is causing intermittent whiteout conditions. They also say roads in town may be icy. 

A Category 1 advisory means drivers should use caution. Category 2 means to only drive if necessary. Category 3 indicates road closures. 

A blizzard watch will be in effect for the Eastern Aleutians on Thursday and Friday.