July 2016 Observation and Model Discussion for the Pacific Northwest

[TT-SEA]

 

 

Went back to check on accuracy.   Above image was from last Wednesday evening.   Actual highs through yesterday:

 

7/14 - 76  (4 degrees too cold)

7/15 - 76  (3 degrees too cold)

7/16 - 73  (2 degrees too warm)

7/17 - 79  (5 degrees too cold)

7/18 - 71  (1 degree too cold)

 

 

Its generally running too cold... the only exception was the stubborn marine layer day on Saturday.     Interestingly it was too cold by 4 degrees even for day 1.

[TT-SEA]

Bookmarked and screenshot, just in case you decide to delete this post later.

 

Warmth the last week of July? Is this another "gut feeling"? That method of reasoning hasn't exactly benefited you to this point.

 

Did you still have my post bookmarked?  

[TT-SEA]

76 at SEA now... might end up at 77 or 78.    So that is another day that the ECMWF forecast above was too cold.   That makes 5 out of 6 days.   And its been too cold on the lows across the board as well.    Probably going to be a too cold for tomorrow as well.  

 

SEA is at +2.5 for the day now.   

[TT-SEA]

77/60 at SEA today.    Nice day.  

[Phil]

 

 

Went back to check on accuracy. Above image was from last Wednesday evening. Actual highs through yesterday:

 

7/14 - 76 (4 degrees too cold)

7/15 - 76 (3 degrees too cold)

7/16 - 73 (2 degrees too warm)

7/17 - 79 (5 degrees too cold)

7/18 - 71 (1 degree too cold)

 

 

Its generally running too cold... the only exception was the stubborn marine layer day on Saturday. Interestingly it was too cold by 4 degrees even for day 1.

Sure, and it busted warm @ OLM/PDX. The SEA station has just been a hotspot for some reason, either via unknown microclimatic tendencies or sensor issues.

[TT-SEA]

Sure, and it busted warm @ OLM/PDX. The SEA station has just been a hotspot for some reason, either via unknown microclimatic tendencies or sensor issues.

 

 

On average... you can add 3 degrees to every reading it shows for SEA.    Keep that in mind.    Its still going on. 

[Phil]

Did you still have my post bookmarked?

Careful, I hit SEA exactly on the nose for June (+2.6). I think I'm going to beat you in the forecast contest, too.

[Phil]

If it means anything, my idea of a warm first half of August looks to be in trouble. Again, mid-latitude wavetrain exceptionally synchronized with tropical forcing, little in the way of residual lag. This is a textbook shift the global background state as reflected via the angular momentum budget.

 

There's a good chance the ridging I foresaw through the first half of August will actually occur in late July, retrograde sometime in early August. Once again, I might be a week too slow. We'll see.

[James Jones]

Sure, and it busted warm @ OLM/PDX. The SEA station has just been a hotspot for some reason, either via unknown microclimatic tendencies or sensor issues.

The SEA "issue" isn't rocket science. It's had a relatively big increase in UHI in the recent past (ask Flatiron about the runway issues) so the 1981-2010 normals aren't totally representative of the current station, and combine that with more afternoon clearing than most places in the region this month and you've got a recipe for slightly warmer than expected results. The sensor is reporting the actual temperature at SEA, it's just that land use changes have made the area a little warmer than it used to be.

[Phil]

The SEA "issue" isn't rocket science. It's had a relatively big increase in UHI in the recent past (ask Flatiron about the runway issues) so the 1981-2010 normals aren't totally representative of the current station, and combine that with more afternoon clearing than most places in the region this month and you've got a recipe for slightly warmer than expected results. The sensor is reporting the actual temperature at SEA, it's just that land use changes have made the area a little warmer than it used to be.

I guess that'd explain why the ECMWF is performing well everywhere except @ SEA.

[TT-SEA]

The SEA "issue" isn't rocket science. It's had a relatively big increase in UHI in the recent past (ask Flatiron about the runway issues) so the 1981-2010 normals aren't totally representative of the current station, and combine that with more afternoon clearing than most places in the region this month and you've got a recipe for slightly warmer than expected results. The sensor is reporting the actual temperature at SEA, it's just that land use changes have made the area a little warmer than it used to be.

 

 

Portland has grown as well.

 

And the temperature at SEA has been a little cooler than the temperature lakeside at WFO SEA.     

 

So the entire area is just warmer than it used to be.    A little closer to perfection.  

[Front Ranger]

Portland has grown as well.

 

And the temperature at SEA has been a little cooler than the temperature lakeside at WFO SEA.     

 

So the entire area is just warmer than it used to be.    A little closer to perfection.  

 

You can appreciate that, and those of that care about modern comparisons to climatological records can appreciate stations like OLM, downtown Portland, and EUG. 

[TT-SEA]

You can appreciate that, and those of that care about modern comparisons to climatological records can appreciate stations like OLM, downtown Portland, and EUG. 

 

Very true.

 

Cliff Mass has said that Stampede Pass has shown very little change in recent decades.

[TT-SEA]

Careful, I hit SEA exactly on the nose for June (+2.6). I think I'm going to beat you in the forecast contest, too.

 

 

Careful... you made it clear that my forecast for this week and for next week was wrong.   Just like you told me I was going bust with troughing July 1-10.

 

The monthly contest was completed in late May.   Things have changed.  I am talking about more recent forecasts for July.  

[James Jones]

Portland has grown as well.

 

And the temperature at SEA has been a little cooler than the temperature lakeside at WFO SEA.     

 

So the entire area is just warmer than it used to be.    A little closer to perfection.  

They have, but PDX has generally been running slightly cooler anomalies in recent years compared to SEA. It could be related to the dominant weather patterns we've had but this seems like a long enough period that the noise would be muted. I really don't think this UHI thing is that big of a deal though, it just means you have to put the anomalies in context. I would love it if we had Portland and Seattle based stations that remained in the same spot with no land use changes for the last 150 years, but that's not how it turned out.

 

And yeah, the area is warmer than it used to be... a mix between global warming and increasing UHI.

[James Jones]

You can appreciate that, and those of that care about modern comparisons to climatological records can appreciate stations like OLM, downtown Portland, and EUG. 

Even the downtown Portland station moved in 1973, and the new spot runs cooler than the old one. I remember reading an explanation from Mark Nelsen (or maybe a NWS guy?) about it a few years ago.

[Phil]

Careful... you made it clear that my forecast for this week and for next week was wrong. Just like you told me I was going bust with troughing July 1-10.

 

The monthly contest was completed in late May. Things have changed. I am talking about more recent forecasts for July.

Maybe things have "changed" from your perspective, but not mine. The underlying low frequency progression(s) are behaving exactly as I suspected.

 

Forecasting tendencies down to a weekly/subweekly resolution is pure luck outside ~ 20 days. Bragging about nailing a "forecast" like that is analogous to bragging about correctly guessing the powerball numbers.

[TT-SEA]

Maybe things have "changed" from your perspective, but not mine. Low frequency progression(s) behaving exactly as I suspected.

 

Overall yes.

 

But you did not believe me about July 1-10 troughing... or a warming trend this week... or warm next week.     You need to stop arguing with me about timing and just adjust 10-12 days ahead.  

 

I got the timing down this month.... which ended up the reverse of what you were thinking originally (warm first half and cold second half).

[Phil]

Overall yes.

 

But you did not believe me about July 1-10 troughing... or a warming trend this week... or warm next week. You need to stop arguing with me about timing and just adjust 10-12 days ahead.

 

I got the timing down this month.... which ended up the reverse of what you were thinking originally (warm first half and cold second half).

Specifically timing intraseasonal/subweekly transitions is mostly luck, because there are so many moving parts involved that an delay/advance timing of the said transitions. These "moving parts" are metaphorical shapeshifters, so pegging them down is extremely difficult. The most gifted forecasters and most advanced modeling continue to fail when it comes to forecasting these inherent instabilities.

 

Not to be rude, but you're sounding like a complete ignoramus right now.

[Front Ranger]

Even the downtown Portland station moved in 1973, and the new spot runs cooler than the old one. I remember reading an explanation from Mark Nelsen (or maybe a NWS guy?) about it a few years ago.

 

Yeah, but even so if you compare record months, etc, downtown Portland seems fairly in line with OLM. As in, during the past few years when PDX or SEA had a record month, downtown Portland or OLM didn't always, but when OLM did, so did downtown Portland.

 

Even if there is a significant difference in the two downtown locations, I doubt it's as large as the difference SEA has seen over the years. And at least we have records back to 1973 at the exact same location in an already developed area.

[Front Ranger]

Specifically timing intraseasonal/subweekly transitions is mostly luck, because there are so many moving parts involved that an delay/advance timing of the said transitions. These "moving parts" are metaphorical shapeshifters, so pegging them down is extremely difficult. The most gifted forecasters and most advanced modeling continue to fail when it comes to forecasting these inherent instabilities.

 

Not to be rude, but you're sounding like a complete ignoramus right now.

 

After flailing in May/June, Tim has done well in timing the local patterns this month. Of course there's some luck involved.

[TT-SEA]

Timing intraseasonal/subweekly transitions is mostly luck, because there are so many moving parts involved that an delay/advance timing of the said transitions. These "moving parts" are metaphorical shapeshifters, so pegging them down is extremely difficult.

 

Not to be rude, but you're sounding like a complete ignoramus right now.

 

Really?   Name calling again?

 

Local historical data showed this general timing and evolution.   I don't think it is as much luck or random as you think.  There must be a reason it plays out like this... and it probably has to do with the typical expansion of the high in this type of summer after the middle of July.   You have been off on your timing for months and jumping all over me for making guesses at timing that contradicted your forecast.    You should go with my timing.  No offense meant.   

[TT-SEA]

After flailing in May/June, Tim has done well in timing the local patterns this month. Of course there's some luck involved.

 

 

I will mention that I predicted way ahead that April and early May would be very warm and there would be a crash around May 15th.

 

Did not see the early June heat wave.   That was the first sign that my thoughts on the summer had gone horribly off track!  

[Phil]

After flailing in May/June, Tim has done well in timing the local patterns this month. Of course there's some luck involved.

By getting the pattern wrong?

 

There is no westward "death ridge expansion" ongoing. It's going to bifurcate, as I suggested it would if forcing tried to slide it west. The western periphery of the ridge wil eventually retrograde offshore in August.

 

It would probably split the ridge, if it were tropically/WAF forced.

[TT-SEA]

By getting the pattern wrong?

 

There is no westward "death ridge expansion" ongoing. It's going to bifurcate, as I suggested it would if forcing tried to slide it west. The western periphery of the ridge wil eventually retrograde offshore in August.

 

 

Fact remains... the timing worked out and the ridge is expanding westward like I thought.   You bookmarked the post to mock me later!  

 

This whole death ridge thing sure became short-lived if you can even call it that.    In the end... I think too much was made of a strong ridge in the middle of the country for a week in July.    

[Phil]

I'm not going to drag this thread into the trash again. We'll see who had the right idea in the forecast contest.

 

That said, I'd love to hear your forecast for August. Just to start with something foundational.

[TT-SEA]

I'm not going to drag this thread into the trash again. We'll see who had the right idea in the forecast contest.

That said, I'd love to hear your forecast for August. Just to start with something foundational.

Give me credit on the timing and then we can discuss August. It was not all luck and we literally had reverse forecasts for July and it worked out the way I was thinking. I have given you plenty of credit for the big picture. But it totally destroys a viable dialog when you mock for me every prediction and then mock me for bringing up the actual results.

[TT-SEA]

Looks like 80s at PDX the next couple days and probably 80 at SEA.

 

A little preview of next week.

[Jesse]

The average temps the next few days definitely look upsetting.

[TT-SEA]

The average temps the next few days definitely look upsetting.

Solidly above normal up here.

 

And warming up down there.

[Phil]

Give me credit on the timing and then we can discuss August. It was not all luck and we literally had reverse forecasts for July and it worked out the way I was thinking. I have given you plenty of credit for the big picture. But it totally destroys a viable dialog when you mock for me every prediction and then mock me for bringing up the actual results.

You've definitely timed the fine details much better than I have. I've never been good at that.

[TT-SEA]

You've definitely timed the fine details much better than I have. I've never been good at that.

Thanks Phil.

 

I need to look into August. I have not gotten that far yet. Need to look at September too.

[Front Ranger]

Solidly above normal up here.

 

And warming up down there.

Nah, looks slightly above normal overall.

 

Pointing to SEA alone does not work in this case.

[TT-SEA]

Nah, looks slightly above normal overall.

 

Pointing to SEA alone does not work in this case.

 

 

Maybe +4 up here?   

[Front Ranger]

Maybe +4 up here?   

 

+4 average for the next 3 days at SEA? I'll take the under. And raise no higher than +1.5 at OLM. 

[TT-SEA]

+4 average for the next 3 days at SEA? I'll take the under. And raise no higher than +1.5 at OLM. 

 

 

2 days.   Friday will be cooler.  

[Front Ranger]

Last year on this date, SEA put up a +13!!!

[TT-SEA]

Last year on this date, SEA put up a +13!!!

 

 

Followed just after with a string of 5 out of 6 days below normal!    

[Front Ranger]

2 days.   Friday will be cooler.  

 

Jesse said the "next few days". That usually refers to at least 3. Normally if one was talking about 2 days, they would say "next couple". 

 

Why cherry pick Friday out?

[TT-SEA]

Jesse said the "next few days". That usually refers to at least 3. Normally if one was talking about 2 days, they would say "next couple". 

 

Why cherry pick Friday out?

 

I said the next couple days originally.

 

Not cherry picking Friday.   Just that the next couple days look warmer.