Unusually dry April; much different than the last two years!

7pm Monday…

Does it seem that this spring “isn’t so bad” so far? By that I mean we’re getting a nice mix of some wet days but plenty of dry days and sunshine too. Looking at the numbers, that IS the case this year. And it appears the very dry weather is here to stay for another week or two. Last year the first 3 weeks of April were unusually cold and wet…so apparently this is makeup for that? These stats are from April 1st-23rd LAST YEAR

We’ve seen less than 1″ rain in Portland so far this month; ignore McMinnville, that sensor has been offline for awhile.

Plenty of dry days this month too; I’ve noticed my garden is relatively dry for mid-April, that’s after a slightly dry March (compared to normal).

What a contrast to the 5″+ rainfall months the past two Aprils!

WHAT’S AHEAD?

I see more drier-than-average rainfall as we move through the 2nd half of the month.

1. Drier than normal weather likely continues for another 7-14 days
2. Temperatures will also be warmer than average since we won’t have many wet systems around to keep us cool
3. You need to start watering outdoor pots/containers later this week as a dry east wind arrives. Or anything freshly planted in the ground too
4. But don’t worry about grass/shrubs/trees, there is still plenty of water in the ground…for now.
5. There’s no sign of a “hot spell”. In April that would be temperatures in the 80s.

Take a look at 500mb heights; the 15 day (average) anomaly from the GFS model. The warm colors represent higher than average heights; more ridging than normal. In general we’ve got ridging over the west more often than troughing. That equals warmer/drier vs. cooler/wetter

An animation showing the same product from the Euro model ensembles. It looks similar. Technically this is a 7-day average starting one week out and going to two weeks out in time. So much orange/red! Reminds me of last summer when we saw so much of the tropics and subtropics with above normal heights.

And one more…precipitation anomaly (from ECMWF/Euro) over the next two weeks…dry West Coast! Well, not dry, but much drier than normal.

The actual numbers say less than 1″ rain in these next two weeks in western valleys of Oregon and SW Washington

That’s it for this evening…we’ve just got a few sprinkles tomorrow, then a very weak trough Saturday for a shower chance once again. Enjoy the sunshine this week!

A surprisingly wet El Niño, plus a challenging mountain ski season

7pm Wednesday…

I’m back from a road/flying trip to Dallas for the solar eclipse. It was a great week traveling through the Intermountain West and southern Rockies with my son. Three days of mountain biking in Utah, hot springs in southern Colorado, and great New Mexican food in Santa Fe. Who knew that spicy red and green stuff could be SO good? We also toured Los Alamos since I’m a big history fan.

You already know how eclipse day worked out if you follow me on Twitter or Facebook; my son and I were lucky! The flight from Santa Fe to Dallas on eclipse morning was right on time, then we headed out to one of the airport parking garage roofs. They were all full of people; apparently I wasn’t the only one with that plan. There were no high (cirrus) clouds, just puffy cumulus drifting by with maybe 1/4 sky coverage. In the last 5 minutes before totality the sun was coming and going behind those clouds. In fact in the last minute a great “Nooooo!” could be heard across the roofs as the beginning of totality was behind a cloud. But within 20 seconds, the cloud moved away, leaving us with approximately 2 minutes and 30 seconds of unobstructed viewing. It was just like August 2017, but lasted longer. As always, a surreal experience, but even more so surrounded by an active airport scene; jets taking off on both sides with all their lights on and people inside the glass concourses staring out the windows. The approach of the shadow from the southwest was more obvious to me this time for some reason. Same as when the shadow left. And that “diamond ring effect” as the first rays of light return is just stunning! Flight back to PDX was just two hours later and we were home before sunset; a memorable day!

Alright, it’s time to take a look back at the cool/wet season since we have entered the warmer/drier half of the year in our region. In mid-October I published this outlook: https://www.kptv.com/2023/10/17/winter-2023-2024-el-nio-is-back-will-this-one-be-different/. Then a day later discussed what a moderate-strong El Niño could mean for mountain skiing/snowpack: https://www.kptv.com/2023/10/18/winter-2023-2024-el-nio-isnt-always-bad-news-cascades/

Remember we were expecting a moderate-strong El Niño event this year and that’s what occurred. In fact we are still in moderate conditions right now. The ONI peaked at 2.0 in the November-January period, making it a STRONG El Niño event by that standard. But the MEI, another way of measuring these events, was more in the moderate category, not like the big El Niños of 2015-16, 1997-98, & 1982-83

Many El Niño winters are a bit drier and warmer than normal across our region, but this year only the warmer part worked out. All the moderate-strong winters since 1950 look like this; the typical drier PACNW and wetter California

Average wet season precipitation in moderate/strong El Niño winters

But this year the wetness was a bit farther north. That said, in general it was drier than normal to the north and wetter than normal to the south as one went from British Columbia to California.

Portland has been quite wet and it’s clear our water year will end up wetter than normal once it wraps up in late September

(kptv)

Temperatures were a bit warmer than normal this winter (minus that one week in January!). That was the story all across the USA

Mountain snow pack was surprisingly good in the end…on April 1st most of Oregon was near or above average.

And the December-February critical ski season time APPEARS to be quite good right???

But we had at least two events where heavy snowfall was immediately followed by warm pineapple express rains and melting. Government Camp picked up about 2 feet of snow in early December which all melted. The 36.5″ monthly total at Govy meant nothing because all of it melted and there was little/no snow on the ground during the two week Christmas Break. Again, 90″ of snow fell there in January. But by the first week of February only 14″ was left on the ground after unusually warm late January weather. Mid-February onward was fine though as another series of snowy storms brought the snowpack up to around 4 feet which lingered through most of March. The mountains had plenty of snow this winter, but timing was terrible and it was often followed by warm/wet weather.

That’s it for this evening. We have pretty typical April weather ahead with some sunny and warm days but some showery days too. There’s no sign of an extended warm spell OR extended wet/cool spell. Not so bad this year compared to the cold/wet weather last early/mid April.