High temperatures close to 70 degrees possible

PORTLAND, Ore. (KOIN) — It has been 170 days since Portland felt a temperature of 70 degrees (October 2, 2021).

On Tuesday in the Portland metro area, we have an early spring surprise in our weather forecast: the possibility of a 70-degree day.

Temperatures have hovered around 50 this month. There were a few days where we also made our way into the lower 60s. It’s a bit earlier than our average, but it looks like we’re about to explode, opening the door to 70 degree temperatures this year. The first average 70-degree day occurs on April 2. This is based on the last 30 years in Portland at the airport. We may have a 20 degree rise from Monday’s high to Tuesday’s high this week. This is the type of change that is noticeable right from the start.

We won’t be discussing 80 degree or 90 degree weather for a while, but if you’re curious, you can find a graph in the slideshow below. We are still counting on more 70 degree days in the forecast before moving to the next level.


A massive ridge pushing up clouds and rain this evening. This is expected to form over the Pacific Northwest (PNW) on Tuesday afternoon. The weather graph in the slideshow below will represent these outlooks. This will draw in some warmer air, also turning the wind seaward around the valley. This mechanism tends to warm the surface of the valley due to the air coming down from the mountains. The combination of this event should help create a warm spring day, peaking at nearly 70 degrees. It will be a large ridge that won’t hang around for very long. Portland’s recent temperatures barely hit 60 degrees in the past 10 days. Temperatures mostly fluctuate between the lower 50s and upper 50s. That’s typical for this time of year, even with the normal high in the upper 50s now. The hottest day this month so far was 62 degrees. We also had several 40 degree days this month due to the gloomy and rainy weather.

If you look at the temperature trend for the rest of the week (slideshow), you’ll see that temperatures then bounce back into the upper 50s and lower 60s on Wednesday and beyond. Long-term forecasts may change, but it looks like we will remain near or below average at the end of the month. We’ll have to keep an eye out for the last days of March to see if we can bring in a bit more heat. The powerful, but short-lived ridge will move eastward on Wednesday. This will bring our early spring treat back to the closet for a little while.

Choose the temperature in your community from the graph below. You can give or take a few degrees depending on your location relative to the nearest town below. Temperatures in the valley to jump into the upper 60s in the afternoon. Most places are warming up to the 60s today. For those of you checking this out from the northwest coast of Oregon, you might be a little cooler. Highs are forecast in the upper 50s for Astoria in the afternoon. If you fancy taking a trip south on Highway 101, you’ll find the hottest temperatures of the day.

Today’s highs can be suppressed to the 50s for parts of central and eastern Oregon.

Dale D. Schrum