Oregon – A crisp chill hangs in the Willamette Valley this morning as temperatures dip to around 37°F, leaving patches of frost across parts of Eugene before sunrise. Cold air pooling in the valley could make grassy areas sparkle briefly before clouds begin to increase later in the day.
According to the National Weather Service in Portland, areas of frost may develop early before skies turn mostly cloudy with afternoon temperatures climbing to about 55°F. Winds remain calm, allowing the cool morning air to linger across the southern Willamette Valley.
Conditions change quickly as the week begins. Sunshine returns Monday and temperatures jump to around 71°F, delivering a noticeable burst of spring warmth across Eugene and nearby communities including Springfield, Junction City, and Cottage Grove.
Drivers heading out early along Interstate 5, Highway 126, and Beltline Road should remain cautious where frost lingers on bridges or shaded pavement during the morning hours.
By St. Patrick’s Day Tuesday, clouds increase again as the next Pacific system approaches the Pacific Northwest. Temperatures remain mild near 69°F, but a slight chance of rain could develop later in the day.
Unsettled weather continues through midweek. Wednesday brings another slight chance of rain with highs near 70°F, while clouds dominate the sky across Lane County.
A more organized system may bring better rain chances by Thursday, returning the familiar damp spring pattern to western Oregon.
Meteorologists say the shifting pattern reflects a typical March transition as warmer spring air battles incoming Pacific moisture.
Five Day Outlook for Eugene, Oregon
Today: Areas of frost early, then mostly cloudy. High near 55°F.
Monday: Mostly sunny and warm. High near 71°F.
Tuesday (St. Patrick’s Day): Mostly cloudy with slight rain chance. High near 69°F.
Wednesday: Slight chance of rain. High near 70°F.
Thursday: Chance of rain with highs near 69°F.
