August 2016 Observations and Model Discussion for the Pacific Northwest

[Front Ranger]

I think our inability to come up with a below normal August this century is all related to our inability to get a cold January. We are stuck in a rut. This month could still pull it out, but it's looking less likely.

 

SEA should have easily pulled three consecutive days in the -6 to -9 bracket out of this ULL and it didn't come close.

 

Well again, you can't just look at SEA for anomalies...I mean, you can, but not for accurate comparisons to the past.

 

OLM has had a number of below normal Augusts this century. 2010-2012 Augusts were all easily below normal, and 2009, 2007, 2006, 2002, and 2001 were also cooler than normal.

 

I think what you're looking for is a very cool August.

[snow_wizard]

I guess the good thing you can say about the last few model runs is they don't show a Western death ridge developing. It's pretty much up for grabs how the second half of the month will pan out.

[TT-SEA]

I guess the good thing you can say about the last few model runs is they don't show a Western death ridge developing. It's pretty much up for grabs how the second half of the month will pan out.

The large trough and the large ridge on previous runs appears to have been an incorrect and exaggerated response to tropical systems in the WPAC. Neither seem to be in play now.

[James Jones]

Well again, you can't just look at SEA for anomalies...I mean, you can, but not for accurate comparisons to the past.

 

OLM has had a number of below normal Augusts this century. 2010-2012 Augusts were all easily below normal, and 2009, 2007, 2006, 2002, and 2001 were also cooler than normal.

 

I think what you're looking for is a very cool August.

As always with these modern cold anomalies, they're a lot less fun if you're willing to look at the entire period of record rather than just the 1981-2010 averages. Looking at the months you listed based on OLM's entire period of record:

 

2012: +1.2 (and .5 above normal even using the 1981-2010 averages, by the way)

2011: -.4

2010: -.3

2009: -.3

2007: -1

2006: -1

2002: -.8

2001: -.6

 

None of these months are particularly impressive. And OLM's period of record isn't even that long, only starting in 1948 - obviously, had they started recording at the beginning of the 20th century, the period of record would be considerably cooler and make these recent Augusts look even less impressive.

[snow_wizard]

It's pretty interesting looking at the rankings since 1895 for the Puget Sound Lowlands. It turns out August and January both went warm right after 1980. For the Puget Sound Lowlands as a whole there has not been a below normal August since 2000. At the same time there have only been 3 below normal Januaries since 1993, and they were BARELY below. I'm betting we will see below normal Januaries and below normal Augusts return about the same time. Which one will turn first is completely up in the air.

 

Another interesting thing I found on there is Washington state ranked 47 out of 121 for temperature in July this year while the Puget Sound lowlands ranked 92 out of 121. A pretty huge discrepancy.

[James Jones]

It's pretty interesting looking at the rankings since 1895 for the Puget Sound Lowlands. It turns out August and January both went warm right after 1980. For the Puget Sound Lowlands as a whole there has not been a below normal August since 2000. At the same time there have only been 3 below normal Januaries since 1993, and they were BARELY below. I'm betting we will see below normal Januaries and below normal Augusts return about the same time. Which one will turn first is completely up in the air.

 

Another interesting thing I found on there is Washington state ranked 47 out of 121 for temperature in July this year while the Puget Sound lowlands ranked 92 out of 121. A pretty huge discrepancy.

Just to illustrate your point:

 

http://i.imgur.com/rmO30OX.png

 

http://i.imgur.com/P1SuDQK.png

 

I'd like to know how this tool handles UHI, if at all, though.

[snow_wizard]

Just to illustrate your point:

 

 

 

I'd like to know how this tool handles UHI, if at all, though.

A good number of the stations are rural or semi rural. That makes it much more useful than using strictly city records.

[BLI snowman]

Just to illustrate your point:

 

 

 

I'd like to know how this tool handles UHI, if at all, though.

 

Those are the regional rankings, so it incorporates every COOP station throughout the Puget Sound region (I believe a 4 or 5 county swath).  Many of them are rural and suburban and therefore not very heavily UHI influenced, but the UHI stations are obviously included also. 

 

It's probably very fair to say that we have now gone 16 years (2000) since our last regionally cold August.

[snow_wizard]

The ECMWF agrees with the GFS in showing relatively high height zonal flow for the 6 to 10 day period. Temperatures will pretty much be at the mercy of surface pressure gradients.

[Front Ranger]

As always with these modern cold anomalies, they're a lot less fun if you're willing to look at the entire period of record rather than just the 1981-2010 averages. Looking at the months you listed based on OLM's entire period of record:

 

2012: +1.2 (and .5 above normal even using the 1981-2010 averages, by the way)

2011: -.4

2010: -.3

2009: -.3

2007: -1

2006: -1

2002: -.8

2001: -.6

 

None of these months are particularly impressive. And OLM's period of record isn't even that long, only starting in 1948 - obviously, had they started recording at the beginning of the 20th century, the period of record would be considerably cooler and make these recent Augusts look even less impressive.

I was looking at OLM's entire period of record. Your numbers don't match the WRCC numbers.

 

EDIT: I see the issue, I was looking at July instead of August on the WRCC site for some years. Still, 2011, 2010, 2009, 2007, 2006, 2002, 2001, and 2000 were all below the long term, period of record average at OLM.  Half the years so far this century.

[TT-SEA]

The ECMWF agrees with the GFS in showing relatively high height zonal flow for the 6 to 10 day period. Temperatures will pretty much be at the mercy of surface pressure gradients.

 

So you are saying our snowy January will be determined by the whims of onshore flow and marine layer in mid-August?     

 

Maybe in a warming climate... some months don't warm uniformly?     But having an inversion next week would not make it snow in January.    I think that should be rather obvious.      

[Phil]

Looks like the models are finally figuring out the tropical systems...and hence the change for the weekend and next week locally.

They'll flip cool for late August IMO. Hifreq WAF props into lowfreq Niña waveguide by the 3rd week of August should result in NPAC height rises during the 4th week of the month, and downstream western troughing from then into at least the first week of September.

[Phil]

The large trough and the large ridge on previous runs appears to have been an incorrect and exaggerated response to tropical systems in the WPAC. Neither seem to be in play now.

Well, now do you realize that tropical forcing (in general) indeed plays an important role in your weather, year round?

 

The biggest shift in balance over the last 50yrs is not the planetary warming, rather, it's the Hadley cell expansion & associated poleward jet retraction (which has had an exaggerated effect on the Western US and Europe, less impact on the Eastern US and Siberia/China et al).

[Front Ranger]

Great. Thanks for the update to tell us troughing will eventually return.

 

August might be playing out a little less troughy than you indicated earlier.

 

It's definitely played out troughier/cooler so far than you were thinking in late July. 

[TT-SEA]

It's definitely played out troughier/cooler so far than you were thinking in late July.

I said 8/5 to 8/15 at one point. Might have been a little too aggressive.

[Jesse]

A light mist falling in Vancouver this morning. Quite lovely.

[ShawniganLake]

Uh, I said mid-August ridging, late-August troughing a few days ago, and you agreed with me.

 

What's wrong with you, dude?

You said no support for sustained ridging in August.  What would constitute sustained ridging? 

[Phil]

You said no support for sustained ridging in August. What would constitute sustained ridging?

Sustained (on a subseasonal scale) = multi-week.

[Front Ranger]

I said 8/5 to 8/15 at one point. Might have been a little too aggressive.

 

You said a lot of things at different points, but towards the end of July you definitely said 8/1 - 8/10 would end up warm. Oh wells.

[TT-SEA]

You said a lot of things at different points, but towards the end of July you definitely said 8/1 - 8/10 would end up warm. Oh wells.

Oh wells.

 

Also said that did not work out and it would be cool.

 

Big deal.

 

I don't control it.

[TT-SEA]

I did not have a good feeling about August either way. Just glad the troughing happened part of this week and next week looks nice.

[Front Ranger]

He does not even talk facts... just turns it personal immediately.

 

And he defines everything as troughing here unless it 95-100 degrees.

 

Call it whatever you want. Looks nice.

 

Hyperbolic statements are so fun.

[Jesse]

If this forum is about anything, it is feelings.

[Jesse]

It's kind of funny how we're expected to "move on" when an easily above average ten day period ends up below average, but when things swing the other way it gets driven home until our eyes bleed.

[TT-SEA]

It's kind of funny how we're expected to "move on" when an easily above average ten day period ends up below average, but when things swing the other way it gets driven home until our eyes bleed.

Mentioned the model trends a couple times since yesterday. Eyes bleed?

 

Wow.

[Jesse]

PDX *could* pull off a sub-70 high today.

[TT-SEA]

12Z Canadian and 12Z GFS look great.

 

This is in contrast to my previous updates that the models looked really troughy.

[TT-SEA]

SEA is almost guaranteed a sub-70 high today. Always shown to be the coolest day with thick marine layer.

[snow_wizard]

You said no support for sustained ridging in August.  What would constitute sustained ridging?

The models aren't showing any sustained ridging in the believable range. Pretty much zonal flow for the 6 to 10 day period.

[Geos]

Sitting at 60° with heavy overcast this morning.

Some say it will be a cool August, some warm to hot. Well - we'll eventually see how it plays out.

 

GEFS has the Pacific Northwest largely above normal in the next 2 weeks.

http://www.tropicaltidbits.com/analysis/models/?model=gfs-ens&region=wus&pkg=T2maMean&runtime=2016080912&fh=120&xpos=0&ypos=171

[TT-SEA]

The models aren't showing any sustained ridging in the believable range. Pretty much zonal flow for the 6 to 10 day period.

Yep... just some 80+ degree troughing and zonal flow. Call it arctic air if you want.

[snow_wizard]

Yep... just some 80+ degree troughing and zonal flow. Call it arctic air if you want.

Yep... just some 80+ degree troughing and zonal flow. Call it arctic air if you want.

We'll see. The warmth gets knocked back on Sunday and Monday and another push could easily emerge on the models for later next week.

[Jesse]

We'll see. The warmth gets knocked back on Sunday and Monday and another push could easily emerge on the models for later next week.

Indeed. The 12z GFS ensembles don't look torchy by any means.

 

And it's a decent pattern for surprise marine layer days.

[TT-SEA]

We'll see. The warmth gets knocked back on Sunday and Monday and another push could easily emerge on the models for later next week.

We will see. January snow hangs in the balance of the marine layer intrusion strength next week!

[Jesse]

Is it ok to like cool summer weather for its own sake?

[TT-SEA]

Is it ok to like cool summer weather for its own sake?

Sure.

 

Jim stated his concerns for January so it's being referenced.

[Deweydog]

What's NOT okay is diversity in your likes/dislikes.

 

Either you're in or you're out.

[Jesse]

What's NOT okay is diversity in your likes/dislikes.

 

Either you're in or you're out.

I disagree. We are all part of a beautiful rainbow of mental illness.

[Jesse]

The 12z Euro is nice. Cooler overall than the GFS.

 

I like the tendency toward offshore ridging rebuilding toward the end of the run.

[snow_wizard]

The 12z Euro is nice. Cooler overall than the GFS.

 

I like the tendency toward offshore ridging rebuilding toward the end of the run.

Looks poised for an amplifying GOA ridge in the 11 to 15 day period.