June is here and it is STILL wet.
That said, the last 3 days were quite nice with temperatures peaking around 80 each day and dry for most of us. Portland made it to 81 degrees Thursday, one of the latest “first 80 degree days” we’ve seen
Meteorological spring has ended and we are now officially in summer in the northern hemisphere. June, July, & August are the warmest months so that’s summer. The big question: was it the wettest and coolest spring on record? Not at all. Yes, a bit cool, and wetter than normal, but not a “record-setter”. Take a look at the temperatures in Portland
March-May was only a bit below average because March was so mild. If you take JUST April plus May, it was in the top 1/3 coolest springs, but not near the record. In both Portland and Salem, it was the coolest spring since 2012 or 2011. What’s most interesting is that temperatures this spring were more/less considered “normal” during the cool decades of the 1950s through 1970s. We were warmer before and of course after that time. For someone between my age and 80 years old, this spring was a bit of a “meh, I’ve seen it before” sort of thing. How about precipitation?
It was Portland’s 8th wettest spring and wettest since 2017. Once again, not THAT bad because a drier than normal March is brought into the average. If we once again take just April plus May? Wettest since 1996 in Portland and wettest since 1993 in Salem. Both cities picked up around 9.50″ rain in those two months. For fun, I added up some REALLY big numbers. Astoria saw 13″ rain in those two months. Detroit Lake 28.04″! That’s over two feet of rain in two months. That’s why there are so many large & green trees on the west slopes of the Cascades. Log Creek, a weather station in Portland’s Bull Run Watershed (across the ridge from Lost Lake) was similar; 25.40″ precipitation since April 1st. It’s been an amazing two months of recovery over much of the region.
The reason we’ve been so wet and cool is that we haven’t seen any sort of persistent upper-level ridging in the atmosphere overhead. So a (weak) May and now early June jet stream can still send weather systems our way.
IT APPEARS THIS PATTERN WILL CONTINUE THROUGH AT LEAST THE NEXT 7-9 DAYS. There’s no sign of a sustained warm/dry period through the first 10+ days of June.
This evening we’ve got a relatively strong jet stream aimed at the West Coast. Look at the “Integrated Vapor Transport” showing all the moisture headed our way.
By tomorrow evening, a 150mph jet stream is sending moisture directly into the region. That’s up around 30,000′…strong for June.
So we’ve got a strong jet stream, plenty of moisture, and it’s warm-ish. That means the potential is there for significant rainfall this weekend. Latest models are sending several surges of rain inland tonight through Sunday evening. The heaviest should be Saturday evening and overnight into early Sunday morning. Evening GFS model gives all areas west of the Cascades 0.50″ to 1.50″ rain by Sunday evening!
Other models are a little heavier, or have the heaviest rain in different areas.
Regardless. ALL parts of the region will get at least some rain this weekend, just like last weekend. Our latest GRAF model shows 1/4″ to 1/2″ rain in even the driest parts of Central and North-Central Oregon by Monday morning…excellent news for you folks!
So…hunker down for the weekend, put out some more slug bait around your favorite flowers, and get ready for at least a few nicer weather days once again next week. At least no worries about fire weather!
I’ll be down at the Starlight Parade on Saturday evening and I’m expecting a soaker. Remember our coverage (on TV) starts at 8pm, probably the best place to enjoy the floats and bands!
Chief Meteorologist Mark Nelsen