July 2019 Weather Discussion for the PNW

[ShawniganLake]

Euro looks cooler than the gfs.

[TT-SEA]

Euro looks cooler than the gfs.

At least its sunny from Friday afternoon basically through the end of run. Weekend looks gorgeous. It shows a little marine layer in the morning on day 10... but that is it.

[jcmcgaffey]

Yeah... the models have over-promised better weather for about a month now. It has to happen eventually. Even years like 1954 and 1983 had considerable stretches of nice weather.

 

It rained on just 1 day in North Bend from 7/22 through 8/13 in 1954. Many considered that to be the year without summer and even that year had a 3-week stretch of dry weather with highs in the mid 70s to around 80.

 

In 1983... it rained on just 3 days from 7/28 through 8/26 here.

 

It has rained on 18 out of the last 28 days here right now... right through the heart of summer. And there are another 3 or 4 days coming up.

I feel like it is a copy of the February to March period earlier this year other than it has been a little warmer than average than that period.

[High Desert Mat?]

At least its sunny from Friday afternoon basically through the end of run. Weekend looks gorgeous. It shows a little marine layer in the morning on day 10... but that is it.

Crisis averted.

[TT-SEA]

Crisis averted.

 

Hasn't happened yet.  

[Phil]

Go Euro! Team Euro!

[Frontal Snowsquall]

At least its sunny from Friday afternoon basically through the end of run. Weekend looks gorgeous. It shows a little marine layer in the morning on day 10... but that is it.

Nice!

[Frontal Snowsquall]

Another warm morning out here.

[TT-SEA]

The blob is definitely back... 

 

[jcmcgaffey]

The blob is definitely back...

 

and that was created without a large ridge

[TT-SEA]

and that was created without a large ridge

 

 

Well... its been very ridgy over Alaska all year.    

[Phil]

[TigerWoodsLibido]

The blob is definitely back... 

 

 

19-20 dud winter incoming. Rip the band-aid off then we can get back to business.

[TigerWoodsLibido]

A bit of rain in Springfield but none at EUG.  Not sure it'll amount to much but it was enough to wet the grass and the car a bit.Currently 63F.

[Phil]

Well... its been very ridgy over Alaska all year.

Part of it is the EPO ridge (re-emergence via subsurface given its multiyear persistence). The other is the more recent downwelling that has occurred thanks to the wind/pressure gradient.

 

Not that it matters to the weather. It’s mostly just pretty colors on a map when we’re talking about cold high latitude SSTs like that.

[TT-SEA]

Part of it is the EPO ridge (re-emergence via subsurface given its multiyear persistence). The other is the more recent downwelling that has occurred thanks to the wind/pressure gradient.

 

Not that it matters to the weather. It’s mostly just pretty colors on a map when we’re talking about cold high latitude SSTs like that.

 

 

I agree... it does not have any implications for winter.

[MossMan]

The blob is definitely back...

 

It’s all Matt’s fault. Thanks Matt.

[Omegaraptor]

Warm mornings, eh?

I think you and HeatRaptor would love these RealFeel temps passing 95*F by 9AM. We’re walking the dog at 6AM now to avoid a sweat shower.

Gross. I was personally rooting for the pattern to switch to cooler nights after the ULL passes because of the drier/sunnier conditions.

[Phil]

The blob is definitely back...

 

The Atlantic has flipped significantly as well. Cold horseshoe replaced with warm horseshoe thanks to the flip in the NAO after a historic 6 year positive phase.

 

And believe it or not, if there is a difference in the Atlantic ITCZ/z-cell structure, then you can expect differences in the IO/Indo-Pacific sector as well (research is expanding in this area). Which teleconnects directly to the EOF domain containing the PMM/EPO/TNH/PDO as we move into the second half of 2019.

 

Not debating which is the chicken/egg (answer is likely neither). But it’s a real planetary line of communication that is indicative of a upcoming or ongoing phase change.

[TT-SEA]

The Atlantic has flipped significantly as well. Cold horseshoe replaced with warm horseshoe thanks to the flip in the NAO after a historic 6 year positive phase.

 

And believe it or not, if there is a difference in the Atlantic ITCZ/z-cell structure, then you can expect differences in the IO/Indo-Pacific sector as well (research is expanding in this area). Which teleconnects directly to the EOF domain containing the PMM/EPO/TNH/PDO as we move into the second half of 2019.

 

Not debating which is the chicken/egg (answer is likely neither). But it’s a real link.

 

 

I just can't believe it! 

 

I was lying awake last night thinking about the z-cell structure.   

[Omegaraptor]

The Atlantic has flipped significantly as well. Cold horseshoe replaced with warm horseshoe thanks to the flip in the NAO after a historic 6 year positive phase.

And believe it or not, if there is a difference in the Atlantic ITCZ/z-cell structure, then you can expect differences in the IO/Indo-Pacific sector as well (research is expanding in this area). Which teleconnects directly to the EOF domain containing the PMM/EPO/TNH/PDO as we move into the second half of 2019.

Not debating which is the chicken/egg (answer is likely neither). But it’s a real planetary line of communication that is indicative of a upcoming or ongoing phase change.

What ramifications does -NAO have for winter? I always hear it talked about in the context of summer. Does it bring more arctic air?

[Phil]

I just can't believe it!

 

I was lying awake last night thinking about the z-cell structure.

Z-cells (Hadley/Ferrel/Polar). Their structure is correlated to the low-frequency state of the annular mode(s), and the acceleration in their axisymmetric cycle of late was a huge contributor to the ridgy 2013-18 period in your area.

 

So you should be awake at night. I can link you to some easy-to-read literature if you want. There’s more to it, of course, but that stagnant +PMM/+NAM made it so d**n easy to go nuclear with ridging out there.

[ShawniganLake]

Icon looks more like the GFS early next week. GEM looks more similar to the euro

[Frontal Snowsquall]

19-20 dud winter incoming. Rip the band-aid off then we can get back to business.

Well the blob was here during the winter of 13-14 and we had 2 Arctic Blast that winter.

[Phil]

What ramifications does -NAO have for winter? I always hear it talked about in the context of summer. Does it bring more arctic air?

It’s about what the NAO represents. Even though it’s not a driver of PNW weather *directly*, it’s *directly indicative* of the larger scale boundary conditions that *do* drive PNW weather (and climate).

 

A true -NAO is indicative of a favorable z-cell/planetary wave structure for maintaining -PNA on a seasonal scale (in essence, equatorward-contracted subtropical highs cyclonic surf across the proper middle latitude WAF/transfer domains, as opposed to poleward anticyclonic surf as seen under strong +NAO/+NAM).

[Deweydog]

It’s all Matt’s fault. Thanks Matt.

When I think of the blob I think of this scene:

 

 

No coincidence that those boxes are orange...

[Omegaraptor]

Well the blob was here during the winter of 13-14 and we had 2 Arctic Blast that winter.

December 2013 was really cool, the only problem was crystal clear skies (which is why it got so cold). Tillamook hit -10°F which is incredible.

 

For some reason, Portland didn’t perform as well. While PDX got to 12, Hillsboro (which isn’t in the UHI and is capable of subzero) only got to 9 for some reason.

 

In comparison, January 2017 bottomed at 11 at PDX and 3 at Hillsboro. Anyone know why?

[ShawniganLake]

December 2013 was really cool, the only problem was crystal clear skies (which is why it got so cold). Tillamook hit -10°F which is incredible.

 

For some reason, Portland didn’t perform as well. While PDX got to 12, Hillsboro (which isn’t in the UHI and is capable of subzero) only got to 9 for some reason.

 

In comparison, January 2017 bottomed at 11 at PDX and 3 at Hillsboro. Anyone know why?

Snowcover probably

[SilverFallsAndrew]

Snowcover probably

 

Yep

[Front Ranger]

Low solar heavily favors both -NAO and -EPO.

 

2013-14 was a -EPO driven winter.

[TT-SEA]

USA... USA!!!

[Timmy]

December 2013 was really cool, the only problem was crystal clear skies (which is why it got so cold). Tillamook hit -10°F which is incredible.

 

For some reason, Portland didn’t perform as well. While PDX got to 12, Hillsboro (which isn’t in the UHI and is capable of subzero) only got to 9 for some reason.

 

In comparison, January 2017 bottomed at 11 at PDX and 3 at Hillsboro. Anyone know why?

I know eug hit -10 at some point maybe not that year but Tillamook? I don’t remember that.

 

Edit: Tillamook hit 10 not negative 10

[Omegaraptor]

I know eug hit -10 at some point maybe not that year but Tillamook? I don’t remember that.

Edit: Tillamook hit 10 not negative 10

Whoops, I was mistaken.

 

Still an impressive cold event. Hope we can get an Arctic Blast this winter. Been a while since we’ve had one.

[Frontal Snowsquall]

December 2013 was really cool, the only problem was crystal clear skies (which is why it got so cold). Tillamook hit -10°F which is incredible.

 

For some reason, Portland didn’t perform as well. While PDX got to 12, Hillsboro (which isn’t in the UHI and is capable of subzero) only got to 9 for some reason.

 

In comparison, January 2017 bottomed at 11 at PDX and 3 at Hillsboro. Anyone know why?

Snowcover probably

Yep

Yeah, it was due to snowcover. I had to drive from Gresham to Hillsboro each morning and it felt like I was on an Arctic Tundra.

[Timmy Supercell]

87B96124-058C-4E91-9E43-5C51EE057A52.gif

 

3F3CC136-9208-434D-9D70-74A0A2F46760.gif

 

So I could be looking at potentially a cooler July than in 2016. Perhaps a coolest in a decade.

[Timmy Supercell]

Well the blob was here during the winter of 13-14 and we had 2 Arctic Blast that winter.

 

Yeah, coolest December in Klamath County in over 40 years. 

[Kayla]

Yeah, it was due to snowcover. I had to drive from Gresham to Hillsboro each morning and it felt like I was on an Arctic Tundra.

 

Lows in the low double digits above zero would be downright balmy up in the Tundra during the winter.

 

They are mostly below zero all winter long up there with an average temp of -20F.

[Timmy Supercell]

Lows in the low double digits above zero would be downright balmy up in the Tundra during the winter.

 

They are mostly below zero all winter long up there with an average temp of -20F.

 

So my low of -20 on 12/08/2013 matched their AVERAGE. Gotcha. 

[MossMan]

[Kayla]

Four corners high really builds in next week. Strongest of the year that is for sure with most of the country roasting.

 

Looks like the immediate PNW maintains enough onshore flow to escape the worst of the heat.