April 2016 Observation and Model Discussion for the Pacific Northwest

[Phil]

You have a weird idea of fun.

I'm a weird guy.

[Deweydog]

FWIW, our last nocturnal thunderstorm event in April in the Portland area was April 29, 1992. Been awhile.

Analogalogalog!!!

[BLI snowman]

Analogalogalog!!!

 

Snowy winter incoming!

[Deweydog]

Snowy winter incoming!

Who cares...

 

What does it mean for this summer!?!?!?!!?!?!?!?!? $?? $!???

[Deweydog]

That thing west of Hillsburrito isn't ******* around.

[ShawniganLake]

There has been a lot of lightning off to the east of Vancouver BC this evening. The eastern Fraser valley has been getting hit for a couple hours.

[Jesse]

That thing west of Hillsburrito isn't ******* around.

We've been watching lightning to our west for a while now.

[Timmy Supercell]

FWIW, our last nocturnal thunderstorm event in April in the Portland area was April 29, 1992. Been awhile. 

 

At first I was thinking 04/29/2003 would have qualified but that was just a tad before sunset It has really been 24 years eh?

[SilverFallsAndrew]

Going to be an extremely wet morning. I hated days like this 15-20 years ago, it meant 100% chance my baseball game would be rescheduled.

[TT-SEA]

Going to be an extremely wet morning. I hated days like this 15-20 years ago, it meant 100% chance my baseball game would be rescheduled.

Not a drop of rain here yet... last rain was a week ago this morning.

[MossMan]

Of course...80's and sun all week until my day off...56 degrees and light rain currently!

[Jesse]

Ahhh....April's back.

[Timmy Supercell]

Between 1 and 3 am in Klamath Falls I had very loud wind gusts. A lot higher than KLMT was reading, they had only 35mph which would be quite a normal wind for here. My walls were rumbling in the wind and it sounded like late Winter. I typically stop having these high wind events after about mid or late March. At least the ones that aren't related to convection. It was pure low-produced winds.

[Farmboy]

Anyone see this new forecast for May?   For anyone interested, this should be a good year for peppers, melons, and tomatoes....

[Jesse]

Anyone see this new forecast for May? For anyone interested, this should be a good year for peppers, melons, and tomatoes....

Looks super legit.

[Timmy Supercell]

All of Oregon, Washington, and Idaho in a chance of t'storms today. Coast tomorrow, and most of Oregon again Sunday!

April is going to be one for the record books for t'storms. Let alone how many K-Falls could have by the end of the month, could be more than I'll get in July or August this year.

 

 

http://i66.tinypic.com/xmmv0l.jpg

 

http://i63.tinypic.com/2cnfpzs.jpg

 

http://i64.tinypic.com/ogjua8.jpg

[Farmboy]

Looks super legit.

Why not, it's from the weather channel....?

[Jesse]

Why not, it's from the weather channel....?

The Euro weeklies tend to be a better guide. I haven't looked yet this week. Maybe they show that too.

[ShawniganLake]

Anyone see this new forecast for May? For anyone interested, this should be a good year for peppers, melons, and tomatoes....

Yep. Probably gonna be a warm May too. Not so sure about late summer though, when peppers and melons are ripening.

[Farmboy]

Yep. Probably gonna be a warm May too. Not so sure about late summer though, when peppers and melons are ripening.

I'm hoping the summer forecasts I've seen are correct, showing above normal temp....

[MossMan]

Wet, breezy, and 54 degrees currently. I already miss this last weeks warmth.

[Jesse]

The warm spell showing up at the end of the month should clench warmest April on record for many spots.

[ShawniganLake]

This april heat is kicking the out of our snowpack up here. 

 

http://bcrfc.env.gov.bc.ca/data/asp/realtime/graphs/spd3b23p.gif

[MossMan]

49 degree heavy drizzle! Even my daughter was singing the "rain rain go away" song!

[TT-SEA]

49 degree heavy drizzle! Even my daughter was singing the "rain rain go away" song!

 

 

Sneaking in a decent Saturday so far... partly sunny and 55 here.

 

Tomorrow looks like an all-day c-zone.

[Jesse]

49 degree heavy drizzle! Even my daughter was singing the "rain rain go away" song!

 

It has been one of our warmest and sunniest Aprils in recorded history. 

[MossMan]

Sneaking in a decent Saturday so far... partly sunny and 55 here.

 

Tomorrow looks like an all-day c-zone.

Centered over you, or me?

[TT-SEA]

Centered over you, or me?

 

 

Probably both.  

[TT-SEA]

It has been one of our warmest and sunniest Aprils in recorded history. 

 

 

Yeah... rain go away.   Normal April pretty much sucks.   

[TT-SEA]

Nice backing off on the trough for next weekend on the ECMWF over the last couple runs.   The 18Z GFS run from Thursday first showed this but was a 'major outlier'.

 

Here is next Sunday morning from the 12Z ECMWF on Thursday:

 

 

http://stream.ecmwf.int/data/atls17/data/data01/scratch/ps2png-atls17-95e2cf679cd58ee9b4db4dd119a05a8d-u8rVW0.png

 

And now next Sunday morning on today's 12Z ECMWF.   Much improved.

 

http://stream.ecmwf.int/data/atls17/data/data01/scratch/ps2png-atls17-95e2cf679cd58ee9b4db4dd119a05a8d-jGeZJT.png

[MossMan]

It has been one of our warmest and sunniest Aprils in recorded history.

Seems like a distant memory now. Heavy drizzle has stopped up here for now anyway!

[Farmboy]

Nice backing off on the trough for next weekend on the ECMWF over the last couple runs.   The 18Z GFS run from Thursday first showed this but was a 'major outlier'.

 

Here is next Sunday morning from the 12Z ECMWF on Thursday:

 

 

http://stream.ecmwf.int/data/atls17/data/data01/scratch/ps2png-atls17-95e2cf679cd58ee9b4db4dd119a05a8d-u8rVW0.png

 

And now next Sunday morning on today's 12Z ECMWF.   Much improved.

 

http://stream.ecmwf.int/data/atls17/data/data01/scratch/ps2png-atls17-95e2cf679cd58ee9b4db4dd119a05a8d-jGeZJT.png

Those are the kind of changes I like!

[Phil]

Latest ECMWF weeklies lock in IO/MT (Niña) forcing during mid/late May. Assuming this comes to fruition, it'd definitely favor a -AAM/-PNA type circulation and speed up the development of La Niña.

 

Basic phase diagram depiction:

 

[Jesse]

Latest ECMWF weeklies lock in IO/MT (Niña) forcing during mid/late May. Assuming this comes to fruition, it'd definitely favor a -AAM/-PNA type circulation and speed up the development of La Niña.

 

Basic phase diagram depiction:

 

 

Awesome. Hoping this pans out.

[Farmboy]

Latest ECMWF weeklies lock in IO/MT (Niña) forcing during mid/late May. Assuming this comes to fruition, it'd definitely favor a -AAM/-PNA type circulation and speed up the development of La Niña.

 

Basic phase diagram depiction:

 

image.gif

What does this mean for May and the upcoming summer?  It's not going to funk it all up with rain is it?

[Phil]

What does this mean for May and the upcoming summer? It's not going to funk it all up with rain is it?

It'd lead to a cooler than average summer, assuming it's correct. I suspect that, as we go through the summer, the tendency towards cooler than average weather will gradually become more frequent/prominent as the -AAM increases in amplitude.

 

The latest JMA weeklies agree with the ECMWF weeklies, in that they begin shift forcing into the IO during May, and obviously are gradually propagating it into the E-IO/MT domain, which would probably lock the Niña/-AAM in for good. Below are the CHI200 anomalies depicted on the JMA weeklies,

 

Week-1 (this week), note the divergence over the Pacific/ (Niño forcing) and subsidence in the IO/MT:

 

 

See the CHI200 depictions (JMA weeklies) below, note the divergence over the IO, propagating eastward into the E-IO/MT weeks 3-5.

 

[Farmboy]

It'd lead to a cooler than average summer, assuming it's correct. I suspect that, as we go through the summer, the tendency towards cooler than average weather will gradually become more frequent/prominent as the -AAM increases in amplitude.

 

The latest JMA weeklies agree with the ECMWF weeklies, in that they begin shift forcing into the IO during May, and obviously are gradually propagating it into the E-IO/MT domain, which would probably lock the Niña/-AAM in for good. Below are the CHI200 anomalies depicted on the JMA weeklies,

 

Week-1 (this week), note the divergence over the Pacific/ (Niño forcing) and subsidence in the IO/MT:

 

image.png

 

See the CHI200 depictions (JMA weeklies) below, note the divergence over the IO, propagating eastward into the E-IO/MT weeks 3-5.

 

image.pngimage.png

So you're saying all these 'warmer than average summer' forecasts haven't taken this new information into account...?

[Phil]

So you're saying all these 'warmer than average summer' forecasts haven't taken this new information into account...?

I don't know what forecasts you're referring to, and I don't really care. All I know is what the available data is telling me.

 

I'm thinking a warm April/May/June overall, followed by a midsummer transition/cooler than average July/August/September overall.

[Front Ranger]

September cooler than April this year?!?

[TT-SEA]

September cooler than April this year?!?

 

 

Did not come even close to happening in 1889, 1942. 1973, 1988, and 1998.     September was WAY warmer than April in all those years.   By 10 degrees or more.

 

Those are the only years that went from strong Nino to start the year to Nina by summer.