April 2019 Weather Discussion in the PNW

[jakeinthevalley]

 

I always wondered what would happen to Big Cliff Dam, would it just blow out immediately? Probably I guess...[/quote

 

It would make for one hell of a rapids for a few seconds!

[Front Ranger]

 

 

Sounds like they think a 100 year rain event could potentially cause dam-breaching and then failure. Kind of surprising they don't already have a warning system in place for an event that theoretically has a 1% chance of happening every year.[/quote

 

A complete failure of the Silver Creek Dam would destroy everything from downtown east within minutes. A warning system would only give you enough time to kiss your own a** goodbye if you lived in that valley.

 

According to the article, the warning system would be triggered before the actual dam failure, ideally. It suggested a warning time of "under an hour".

[Jesse]

 

ame="jakeinthevalley" post="461836" timestamp="1554786006"]

 

 

 

What’s up with the quoting.

[jakeinthevalley]

 

 

ame="jakeinthevalley" post="461836" timestamp="1554786006"]

 

 

 

What’s up with the quoting.

 

No clue. Posting from my phone. Never seen this before

 

As for the early warning for Silver Creek Dam. I remember a lot of concern that it would lead to the "boy who cried wolf" situation if it was activated and nothing came from it

[Jesse]

Definitely a bit of a ridgy signal developing in the long range, but still a good deal of spread as well.

 

[TigerWoodsLibido]

 

ame="jakeinthevalley" post="461836" timestamp="1554786006"]

 

 

 

What’s up with the quoting.

 

Hackers

[Phil]

Latest ENSO updates seem to be trending towards a weak Nino or neutral conditions.

They do? Looks like a slow strengthening to me with the eastern IPWP cooling being one of the precursors you’d look for during boreal spring/summer.

 

[Phil]

There’s also a healthy +IOD but no SIOD signal so this would favor Indo-Pacific subsidence/westerlies over the Pacific once the final warming occurs and the Asian monsoonal trough develops.

[Phil]

FWIW the CMC ensembles are trying to blow up a humongous MJO wave in the west-central IO in the clown range, and the GEFS have a legit niño forcing look around the same timeframe with lots of subsidence between 110E-160E. So things are going to be changing later this month.

[ShawniganLake]

Euro looks cool and active.

[SilverFallsAndrew]

More heavy rain falling. 

[SilverFallsAndrew]

John Day at Service Creek now forecast to crest at 15.7" which would be the 3rd highest crest on record behind December 1964 and January 1, 1997. 

 

Silvies River at Burns is now at flood stage. Which is great news for wildlife in the often drought plagued Harney Basin. 

[TT-SEA]

More heavy rain falling. 

 

 

00Z ECMWF showed rain every day for the next 10 days and no sign of it stopping at day 10.     This has evolved into a very pattern for everyone.    

 

From almost no rain at all... to rain every day.     It would be nice to have something in between.     Just reporting what it shows... I am sure this will be construed and ranting and raving.  

[SilverFallsAndrew]

00Z ECMWF showed rain every day for the next 10 days and no sign of it stopping at day 10.     This has evolved into a very pattern for everyone.    

 

From almost no rain at all... to rain every day.     It would be nice to have something in between.     Just reporting what it shows... I am sure this will be construed and ranting and raving.  

 

Yeah, I agree. I enjoy historic weather so these past few days have been very interesting from that perspective, but I would like to get some work done in the yard at some point without getting soaked. 

[SilverFallsAndrew]

Looks like about 1/2" of rain has fallen since midnight. 8.65" now on the month. 

[Timmy Supercell]

It is lightly snowing now. Nothing accumulating though.

[SilverFallsAndrew]

9" new snow at Timberline overnight. Good to see the snow level finally coming down. ,Snow pack in the Cascades has dipped the past week or two, but we should start to see it bounce back over the next week,

[TT-SEA]

Looks like about 1/2" of rain has fallen since midnight. 8.65" now on the month. 

 

 

What is the wettest April ever there?     

[SilverFallsAndrew]

What is the wettest April ever there?     

 

12.79" in 1955. 

 

https://climate.usu.edu/reports/e15daily.php?stn=USC00357809&year=1955&month=4&unit=EN&network=direct:ghcn&sidebar=0

 

That one actually had nearly a week of dry weather early in the month. It was a very chilly April too with a mean temp of only 41.5. This month conversely has started out very mild with only one low in the 30s so far.

[TT-SEA]

12.79" in 1955. 

 

 

Wow... you are almost 70% of the way to the wettest April in history and its only the 9th day of the month.   

 

Seems very likely that this will end being the wettest April there.

[SilverFallsAndrew]

Wow... you are almost 70% of the way to the wettest April in history and its only the 9th day of the month.   

 

Seems very likely that this will end being the wettest April there.

 

It is very possible. 

 

Interestingly. When I look at historically wet April's up here, most were preceded by a wet March and followed by a wet May (In most cases very wet May). 

 

The only two historically wet April's that followed a dry March were 1958 and 1992. Both of those years also featured dry May's. 

 

Last year was not a historically wet April, but was above average following a dry March. And we know how last May turned out. 

[SilverFallsAndrew]

A couple of other notes. 

 

My soil usually drains really well. However, there are large areas of standing water in my fields and water flowing down along the surface of the upper pasture. Though I have seen about 6" of rain in a little over 3 days, that amount is not uncommon during November-February. Also it is surprising given how dry March was. My guess is the ground is fairly saturated due to the constant snow melt which only ended the last week of March.

 

I also remember mentioning in late March that looking at historical data the rest of spring would likely be dry, however if there was an exception it would probably be April. We will have to see if May flips back to dry. My money would be on that.

[TT-SEA]

It is very possible. 

 

Interestingly. When I look at historically wet April's up here, most were preceded by a wet March and followed by a wet May (In most cases very wet May). 

 

The only two historically wet April's that followed a dry March were 1958 and 1992. Both of those years also featured dry May's. 

 

Last year was not a historically wet April, but was above average following a dry March. And we know how last May turned out. 

 

1958 and 1992 were the same here... very dry March followed by a very wet April and then dry in May and beyond.

[El_Nina]

0.43" here on the day. Playing the radar loop, it shows some major orographics were at play overnight for the east metro.

[SilverFallsAndrew]

1958 and 1992 were the same here... very dry March followed by a very wet April and then dry in May and beyond.

 

I believe both featured hot summers as well. I know there were big heatwaves in June and August 1992. Salem hit 105 with both heatwaves. 

 

I just checked, it also hit 100 at SLE in July 1992! 

[TacomaWaWx]

Wow... you are almost 70% of the way to the wettest April in history and its only the 9th day of the month.

 

Seems very likely that this will end being the wettest April there.

I was getting worried that Oregon was gonna take all the rain this month but it looks like Washington should still get in on the rain the next week or so. This is great news considering 2 weeks ago I was getting concerned that we wouldn’t get much rain before the dry season arrived. Everything is all good now

Have to give Tim credit about 3 weeks ago when I was getting worried he said it would be a wet April and he called it.

[TT-SEA]

I was getting worried that Oregon was gonna take all the rain this month but it looks like Washington should still get in on the rain the next week or so. This is great news considering 2 weeks ago I was getting concerned that we wouldn’t get much rain before the dry season arrived. Everything is all good now

Have to give Tim credit about 3 weeks ago when I was getting worried he said it would be a wet April and he called it.

 

 

I am not sure about that... all I said was that it pretty much had to turn wet after such a long dry period.    That seemed pretty obvious.   

[SilverFallsAndrew]

We should see a bit of a break from the steady rain from later this morning until tomorrow afternoon. It has been raining steadily since some time on Friday.

[TT-SEA]

I believe both featured hot summers as well. I know there were big heatwaves in June and August 1992. Salem hit 105 with both heatwaves. 

 

I just checked, it also hit 100 at SLE in July 1992! 

 

 

Now we will get the inevitable post from Phil about how this year is exact opposite of those years in every possible way.   It could not be more different.   As if we are saying it will follow those years exactly while making conversation about past years with a dry March / wet April combo.   

[SilverFallsAndrew]

Now we will get the inevitable post from Phil about how this year is exact opposite of those years in every possible way.   It could not be more different.   As if we are saying it will follow those years exactly while making conversation about past years with a dry March / wet April combo.   

 

I think both were Ninos like this year. Key difference being those years to this point were much warmer. 

[Omegaraptor]

I wonder what June, the month nobody cares about here, will be like. Hope we get another thunderstorm. Last year was epic.

[TacomaWaWx]

Band of rain has been consistently sitting over Tacoma all morning has given a half inch of rain since midnight. it seems to be a convergence zone off of the Olympics that would usually be up in Everett but it’s not due to the NW flow today.

[ShawniganLake]

I believe both featured hot summers as well. I know there were big heatwaves in June and August 1992. Salem hit 105 with both heatwaves.

 

I just checked, it also hit 100 at SLE in July 1992!

1958 was ridiculously hot in BC, especially in July. Warmest July by a good margin here.

[SilverFallsAndrew]

Actually really pleasant outside right now.

 

[jakeinthevalley]

Actually really pleasant outside right now.

 

Lotta water upstream already in the system just waiting for it's turn to head North. Drove over the river this morning and it's looking like a good one.  Wife had to detour on her trip home from Mt Angel last night due to high water

[MossMan]

https://cliffmass.blogspot.com/2019/04/bountiful-precipitation-and-full.html?m=1

Looks like the majority of the west coast is in good shape water wise.

[ShawniganLake]

BC snowpack is below 80% on the April 8 update.

 

Several regions are down near 50% due to a dry February and March and the spring freshet running 2-4 weeks early in some cases. The cool damp start to April should help some

[ShawniganLake]

[TacomaWaWx]

Investigators are still trying to figure out what caused the power line failures in Tukwila last Saturday. Nobody crashed into the poles, so it had to have been the winds. Power lines may have been weakened over the past couple years with storms and one good blow came through and was enough to knock them down, but there’s still no official cause for what happened.

[TacomaWaWx]

BC snowpack is below 80% on the April 8 update.

 

Several regions are down near 50% due to a dry February and March and the spring freshet running 2-4 weeks early in some cases. The cool damp start to April should help some

Things are starting to look hopeful. Currently though snow pack is lower north of Stevens pass or so, but again that will probably improve soon.