PORTLAND, Ore. (KOIN) – Record rain events in Portland can be tough to tackle. We are known for rain and we are known for a lot of rain. Even on the days that it feels like we should be marking a new record in the record books, we fall short. That hasn’t been the case this year.
We are five months in and we have already established six record rainfall events. Most records depend on timing. It takes some good timing to fall on a day that has an achievable record. It usually takes an event that falls in the 24-hour window of a day, not split between two days. It also depends on the time of the year. Let me tell you, not all records are created equal (more below).
Go ahead and check out the record rain tally graphic below. This tally is the number of records that are currently in place. What does that mean? It is possible that a record was secured in 2016, but then it was topped in 2021. This means that 2016 may have had more records than a few years ago, but currently, only have two rainfall records dating back to 1940. What I find interesting, is that we have 32 rainfall records in place going back to 2015. It also speaks to the larger story, that even with record rain, it doesn’t mean we won’t be in a drought.
Go ahead and digest the record rain dates in the list below. We have had five rainfall records in January. Most of those records fall in the wet seasons. That is because it is when we typically have our deepest moisture. We tend to break records when we have atmospheric rivers that come moving in for an extended period. That isn’t necessarily the case for each record though. We have a few summer rainfall records. You will find that those records are typically not as wet as those in the winter or fall. The records that hit in the summer, are usually due to a strong thunderstorm that produces a high amount of rain in a small amount of time.
I mentioned that not all rainfall records are created equally. Let me show you my favorite rainfall record that is on the list:
August 8, 2016: 0.08″
Talk about a record that you wouldn’t expect. Yes, the summer is dry. Most records in August are fairly low for the wet months. But a record that is below one-tenth of an inch of rain is impressive.
There are three dates on the list that have rainfall records of over two inches of rain. The greatest record going back to 2015 falls on December 7, 2015. That is when we hit 2.67 inches of rain. We also had the wettest December on record in 2015 with15 inches of rain. We had back-to-back records that year, coming in on December 7 and 8 (over four inches of rain).