UPDATE: Frost advisory for Southwest Washington for Thursday, says the NWS

The creation of this content included the use of AI based on templates created, reviewed and edited by journalists in the newsroom. Read more on our AI policy here.

On Wednesday at 10:50 a.m. the NWS Portland OR issued an updated frost advisory valid for Thursday between 1 a.m. and 9 a.m. The advisory is for Cowlitz County Lowlands, North Clark County Lowlands and South Washington Cascade Foothills.

The NWS informs, "Temperatures of 32 to 36 degrees will result in frost formation."

"Frost could harm sensitive outdoor vegetation," explains the NWS. "Take steps now to protect tender outdoor plants from the cold. Consider temporarily moving outdoor potted plants indoors if they are sensitive to cold temperatures, or temporarily covering sensitive plants with a lightweight cotton fabric (i.e., bedsheets, thin blankets), as this will help retain heat and provide frost protection for your plants."

This advisory is in effect until Thursday at 9 a.m.

What to do if there is a frost advisory

Frost advisories are issued from May to October (but can be extended if necessary) when temperatures, winds, and sky cover are favorable for frost development. This is most likely to happen when the temperature is 36 degrees or less. In some cases, the frost is severe enough to end the growing season and is then referred to as a 'killing frost'.

According to the NWS, if a frost advisory is issued for your area, cover up sensitive plants before the sun sets so that it can help retain heat near the plants, or move the plants indoors for the night, if possible.

Source: The National Weather Service

United Robots Washington

This story was originally published April 15, 2026 at 12:45 AM.