May 2017 Observations and Model Discussion for the Pacific Northwest

[Phil]

Definitely warmed up in the Indian Ocean over the last few weeks. I remember a cold IO being part of the forecast for this warm season.

 

http://www.tropicaltidbits.com/analysis/ocean/cdas-sflux_ssta_global_1.png

It's more about the zonal SSTA gradient between the IO and Pacific than the absolute SSTAs in either area.

 

Also, that CDAS SST data is running very warm compared to every other dataset. So, I would take that into account.

[TT-SEA]

It's more about the zonal SSTA gradient between the IO and Pacific than the absolute SSTAs in either area.

 

Also, that CDAS SST data is running very warm compared to every other dataset. So, I would take that into account.

 

I checked some other maps and none of them show a cold Indian Ocean now... as was the case earlier in the spring.  

[Jesse]

Definitely warmed up in the Indian Ocean over the last few weeks. I remember a cold IO being part of the forecast for this warm season.

 

 

I think the forecast was more based on a relatively weak Asian monsoon (which seems to be playing out so far) as opposed to absolute temps in the Indian Ocean.

[TT-SEA]

I think the forecast was more based on a relatively weak Asian monsoon (which seems to be playing out so far) as opposed to absolute temps in the Indian Ocean.

 

 

OK... good to know.   Phil said at one point that any analog right now has to include a cold Indian Ocean.   But obviously there are other factors than just the absolute SSTA in that region.  

[Phil]

I checked some other maps and none of them show a cold Indian Ocean now... as was the case earlier in the spring.

Okay, so I was typing a reply to this while watching some cumulonimbus develop, and a lightning bolt just comes down right in front of me and hits the pavement maybe 40ft away. I'm literally shaking right now.

[Phil]

Of all the close calls I've had (and there have been many) this was by far the closest. It was one of those lightning bolts that repeats itself like 5+ times, so my ears are ringing pretty badly at the moment, haha.

[Phil]

I think the forecast was more based on a relatively weak Asian monsoon (which seems to be playing out so far) as opposed to absolute temps in the Indian Ocean.

Yeah, the weak EASM in tandem with WPAC subsidence would be the conduit here, and cooler waters around 120E theoretically would support such a regime unless we somehow enter an east based La Niña circulation if the EPAC cools enough. However I was not expecting the ISM (Indian summer monsoon) to struggle in tandem with the East Asian summer monsoon (EASM), so this is very interesting.

 

When both are weak, the NH summer wavetrain becomes very amplified, almost winter-like in some cases, with cooling observed in the middle and higher latitudes, and warming observed in the tropics/subtropics.

[Phil]

There aren't many examples of profoundly weak ISM/EASM states occurring together below the intraseasonal level, but there are a few. One of the most profound examples is 1964, but maybe there are others with better ENSO matches. I'll have to analyze this more closely tonight.

[weatherfan2012]

Must have been one of those cells that just pop up out of no where over head where you get little to no warning until it right on top of you.I call those sneak up storms as they sneak up on you.any way that batch is now crossing the bay and weaking as no lighting is being heard on radio.

[Phil]

Must have been one of those cells that just pop up out of no where over head where you get little to no warning until it right on top of you.I call those sneak up storms as they sneak up on you.any way that batch is now crossing the bay and weaking as no lighting is being heard on radio.

Yeah, that's basically how it works during the summer.

[Phil]

At least the tropical projections have stabilized (finally). Appears as if the modeling has settled on June 8th +/- a few days for the return of subsidence to the WPAC/dateline:

 

http://www.tropicaltidbits.com/analysis/models/?model=gfs&region=global&pkg=chi200&runtime=2017053118&fh=-24&xpos=0&ypos=339

[weatherfan2012]

Yeah, that's basically how it works during the summer.

true had a few of those types last summer in a over all lame season thunderstorm wise hopefully we get a couple good events this summer those so far it's been off to a over all poor start once again,

[Phil]

Ignoring the CFS's warm bias, it's roughly in line with the weekly ensemble means from the JMA, GGEM, EPS, NMME, and POAMA, so there's finally some stability in the modeled progression after the intraseasonal hiccup.

 

http://www.tropicaltidbits.com/analysis/models/?model=cfs-avg&region=nhem&pkg=z500aMean&runtime=2017053112&fh=168&xpos=0&ypos=46

[TT-SEA]

Impressive landscape changes... first photo popped up on facebook from 3 years ago today (5/31/14) of a party that my kids were having that day.   Second photo was taken this afternoon.  

 

 

  

[Phil]

Those Fir trees are growing at a snails pace.

[TT-SEA]

Those Fir trees are growing at a snails pace.

 

Feels like they are growing fast... but they don't look too different in those photos.   I saw some pictures from 2005 when we moved into the house and they were tiny in comparison.

[Timmy Supercell]

http://i.imgur.com/tyo6OG4.jpg

[Deweydog]

Feels like they are growing fast... but they don't look too different in those photos. I saw some pictures from 2005 when we moved into the house and they were tiny in comparison.

Firs slow down considerably once they reach about 30 feet or so.

[TT-SEA]

There is the western trough on the 00Z GFS!   This is what I was expecting based on Phil's analysis.   

 

http://www.tropicaltidbits.com/analysis/models/gfs/2017060100/gfs_z500aNorm_us_44.png

 

http://www.tropicaltidbits.com/analysis/models/gfs/2017060100/gfs_T850a_us_44.png

[Phil]

Yet another completely different GFS run.

 

What a strange, convoluted pattern.

[Jesse]

Those Fir trees are growing at a snails pace.

 

I can definitely see a difference.

 

How fast do the ones in your yard grow?

[Phil]

I can definitely see a difference.

 

How fast do the ones in your yard grow?

The ones that haven't reached maturity? I'd say at least 2-4 feet per year, depending on age, species, temperature, and precipitation. We have a few white pines and tulip poplars that are less than 30yrs old and have already reached 70-90ft. A lot of them have come down over the years as a result.

 

The surviving old, mature trees have been here since this area was logged back around 1800, so they're basically maxed out at this point, most having lost their tops decades ago. We only have three of them remaining on our lot.

[Timmy Supercell]

Weather trivia May 31st 20 years ago... The one and only time a Tornado Watch was issued for NE Oregon and Eastern Washington.