* WHAT...Temperatures as low as 34F to 36F under mostly clear skies will result in frost formation.
* WHERE...In Oregon, North Oregon Coast Range Lowlands and Central Oregon Coast Range Lowlands Counties. In Washington, North Clark County Lowlands and South Washington Cascade Foothills Counties.
* WHEN...From 3 AM to 9 AM PDT Sunday.
* IMPACTS...Frost could harm sensitive outdoor vegetation. Sensitive outdoor plants may be killed if left uncovered.