August 2023 Weather in the PNW

[the_convergence_zone]

4 minutes ago, Phil said:

That building Aleutian low fits the evolution of low pass analog composite almost perfectly. Pretty remarkable.

In September the majority of cases see it redevelop closer to the west coast. I think autumn may start fast and hard this year in the PNW, quick flip to wet/stormy marking the seasonal transition. Like the snap of a finger.

Over the past 10 years I would guess that the average start of rainy season around here is September 15 -- with rainy season defined as a couple of consecutive storms. It almost always starts by my birthday which is the 19th. 2022 was a highly anomalous exception.

It would be nice to have a repeat of 2019 when there was a clear and well defined start to the rainy season on September 7. 

[Phil]

1 minute ago, TT-SEA said:

This does not tell the entire story either.   High clouds might be reported as technically being cloudy but it’s not really cloudy.   There is no way it’s dark cloudy here for 75% of the year.    My experience over the last 20 years is that it’s closer to 50%.    Solar radiation would be a better gauge.

That is mean sky cover, not necessarily sunshine hours.

But it’s pretty objective data, satellite radiometers measure the proportion of SW radiation reflected, cross checked w/ surface radiation sensors.

Our personal experiences/recollections are often wrong. Even when we’re certain we’re right.

[Phil]

Just now, the_convergence_zone said:

Over the past 10 years I would guess that the average start of rainy season around here is September 15 -- with rainy season defined as a couple of consecutive storms. It almost always starts by my birthday which is the 19th. 2022 was a highly anomalous exception.

It would be nice to have a repeat of 2019 when there was a clear and well defined start to the rainy season on September 7. 

Idk when exactly it will start, but I’ll wager September will be rockin’ in the PNW this year. Big league jet.

[TT-SEA]

Just now, Phil said:

That is mean sky cover, not necessarily sunshine hours.

But it’s pretty objective data, satellite radiometers measure the proportion of SW radiation reflected, cross checked w/ surface radiation sensors.

Our personal experiences/recollections are often wrong. Even when we’re certain we’re right.

There are many types of clouds... mean sky cover does not tell the story.      Its been sunny here for most of the last 3 months.   If that map was accurate then we would not see a ray of sun from now through next April.     But we have sunny days mixed in all year long.  

[Phishy Wx]

5 minutes ago, Phil said:

Idk when exactly it will start, but I’ll wager September will be rockin’ in the PNW this year. Big league jet.

Probably some big league windstorms if that Jet parks over us for any extended time

[SilverFallsAndrew]

17 minutes ago, Phil said:

That building Aleutian low fits the evolution of low pass analog composite almost perfectly. Pretty remarkable.

In September the majority of cases see it redevelop closer to the west coast. I think autumn may start fast and hard this year in the PNW, quick flip to wet/stormy marking the seasonal transition. Like the snap of a finger.

Wouldn’t that be something. 

[Phil]

Just now, TT-SEA said:

There are many types of clouds... mean sky cover does not tell the story.      It’s been sunny here for most of the last 3 months.   If that map was accurate then we would not see a ray of sun from now through next April.     But we have sunny days mixed in all year long.  

Well I was just up there and it was not sunny the entire time.

Sunny half the time would mean you get as much sunshine as parts of Florida. Which I know is not true because much of my family is from Florida and moved to Seattle. It’s not even close.

[Phil]

6 minutes ago, Phishy Wx said:

Probably some big league windstorms if that Jet parks over us for any extended time

If there was ever a season for a PNW windstorm, it would be 2023/24. Especially in the fall and early part of winter.

Doesn’t mean it’ll happen, but if I lived there I’d be pruning my trees now (looking at you, @MossMan).

[TT-SEA]

2 minutes ago, Phil said:

Well I was just up there and it was not sunny the entire time.

Sunny half the time would mean you get as much sunshine as parts of Florida. Which I know is not true because much of my family is from Florida and moved to Seattle. It’s not even close.

It was sunny in my area the entire time you were here!  

Its probably as sunny or more sunny up here than in Florida in the summer... and the complete opposite in the winter.

 

[Phil]

4 minutes ago, TT-SEA said:

It was sunny in my area the entire time you were here!  

Its probably as sunny or more sunny up here than in Florida in the summer... and the complete opposite in the winter.

 

You really believe North Bend is as sunny as Florida, annually?

Poor guy. You’ve lived in a cloudy climate for so long you’ve lost perspective. Florida summers are actually quite sunny, cloudy days seldom happen at all. 

[Deweydog]

32 minutes ago, Phil said:

That building Aleutian low fits the evolution of low pass analog composite almost perfectly. Pretty remarkable.

In September the majority of cases see it redevelop closer to the west coast. I think autumn may start fast and hard this year in the PNW, quick flip to wet/stormy marking the seasonal transition. Like the snap of a finger.

Word.

[TT-SEA]

13 minutes ago, Phil said:

You really believe North Bend is as sunny as Florida, annually?

Poor guy. You’ve lived in a cloudy climate for so long you’ve lost perspective. Florida summers are actually quite sunny, cloudy days seldom happen at all. 

I didn't say it was sunnier than Florida.   I don't believe its actually cloudy in Florida half the time.  Its generally cloudy here from about late October through the middle of February.   Not nearly as much the rest of the year.     There is no way that the sun is shining here only 20-25% of the year.    I don't care how many maps you show me.   Its just not true.  

Its can be sunny here 25% of the time even in November.    I am sure last November was sunny more than 50% of the time.  

[TacomaWx]

5 minutes ago, TT-SEA said:

I didn't say it was sunnier than Florida.   I don't believe its actually cloudy in Florida half the time.  Its generally cloudy here from about late October through the middle of February.   Not nearly as much the rest of the year.     There is no way that the sun is shining here only 20-25% of the year.    I don't care how many maps you show me.   Its just not true.  

Its can be sunny here 25% of the time even in November.    I am sure last November was sunny more than 50% of the time.  

Yeah those maps don’t make any sense to me either. There’s more sunny days in the Puget sound region than many people realize…especially right near the sound. 

[Phil]

7 minutes ago, TT-SEA said:

I didn't say it was sunnier than Florida.   I don't believe it’s actually cloudy in Florida half the time.  It’s generally cloudy here from about late October through the middle of February.   Not nearly as much the rest of the year.     There is no way that the sun is shining here only 20-25% of the year.    I don't care how many maps you show me.   It’s just not true.  

Sure it is, half the year is dark by default.  Assume you’re thinking relative to possible sunshine hours. And again, that is a map of annual skycover percentage, not sunshine hours.

I’m sure there are days with thin/high clouds that you probably consider to be “sunny”. Heck, the day I landed at SeaTac there was high overcast with sunshine filtering through. That’s why subjective experience is not used as a climate measure.

[TT-SEA]

4 minutes ago, TacomaWx said:

Yeah those maps don’t make any sense to me either. There’s more sunny days in the Puget sound region than many people realize…especially right near the sound. 

Totally agree.   Places close to the Sound are frequently sunny even when it is actually cloudy everywhere else.   

[Phishy Wx]

Yikes

 

 

[Phil]

2 minutes ago, TacomaWx said:

Yeah those maps don’t make any sense to me either. There’s more sunny days in the Puget sound region than many people realize…especially right near the sound. 

Well, we have high resolution satellite data to determine just how sunny it is there relative to other places. Our brains aren’t always the most objective sensors.  

[TT-SEA]

3 minutes ago, Phil said:

Sure it is, half the year is dark by default.  Assume you’re thinking relative to possible sunshine hours. And again, that is a map of annual skycover percentage, not sunshine hours.

I’m sure there are days with thin/high clouds that you probably consider to be “sunny”. Heck, the day I landed at SeaTac there was high overcast with sunshine filtering through. That’s why subjective experience is not used as a climate measure.

And subjectively... after living here for 2 decades... I can honestly say our cloudy reputation only really applies to the winter months.     Specifically November-January.

[Phil]

You can measure it different ways but it doesn’t change the calculation much. Our minds create false truths all the time.

[Phishy Wx]

ummmm

 

[TT-SEA]

2 minutes ago, Phil said:

You can measure it different ways but it doesn’t change the calculation much. Our minds create false truths all the time.

SEA reports cloudy conditions all the time on sunny days.    Because any thin high clouds show up as overcast.    Even when they are barely noticeable.    

 

[Phil]

6 minutes ago, TT-SEA said:

And subjectively... after living here for 2 decades... I can honestly say our cloudy reputation only really applies to the winter months.     Specifically November-January.

Actually, the months where the PNW is cloudiest relative to the rest of the US is Feb-May.

Greatest cloudcover percentage occurs in Nov/Dec, but that’s also the case in other areas. Great Lakes region in particular is very cloudy Nov-Jan, actually similar to Seattle.

[Phil]

6 minutes ago, TT-SEA said:

SEA reports cloudy conditions all the time on sunny days.    Because any thin high clouds show up as overcast.    Even when they are barely noticeable.    

 

Actually ASOS/AWOS sensors report clear conditions during high overcast. When I landed SeaTac was reporting “clear” skies but there was high overcast with filtered sunshine.

Forget what the cloud base limit is for those sensors. But they don’t measure the high clouds like cirrostratus or altocumulus IIRC.

[TT-SEA]

1 minute ago, Phil said:

Actually, the months where the PNW is cloudiest relative to the rest of the US is Feb-May.

Greatest cloudcover percentage occurs in Nov/Dec, but that’s also the case in other areas. Great Lakes region in particular is very cloudy Nov-Jan, actually similar to Seattle.

Not comparing to rest of the country.   The period from November - January is when it seems like its usually cloudy.   Even when its cloudier than the rest of the country from February - May here... it usually doesn't seem like its endlessly cloudy.   2022 notwithstanding!  

[ChristheElohim]

Blue Angles passing Enumclaw now should be flying over Seattle in 10-15 mins

[TT-SEA]

7 minutes ago, Phil said:

Actually ASOS/AWOS sensors report clear conditions during high overcast. When I landed SeaTac was reporting “clear” skies but there was high overcast with filtered sunshine.

Forget what the cloud base limit is for those sensors. But they don’t measure the high clouds like cirrostratus or altocumulus IIRC.

According to F6 data at SEA for July... it was cloudy 40% of the time.   In reality... it was a ridiculously sunny month.   If that is 40%... I wouldn't want to see 20%!   It was endlessly sunny except for a couple very welcome days when clouds were dominant. 

[Phil]

13 minutes ago, TT-SEA said:

Not comparing to rest of the country.   The period from November - January is when it seems like it’s usually cloudy.   Even when it’s cloudier than the rest of the country from February - May here... it usually doesn't seem like it’s endlessly cloudy.   2022 notwithstanding!  

Interesting how different our subjective interpretations can be. My family that moved from FL to WA describes it at the cloudiest place ever except for very sunny summers. But my older cousins that were born in Seattle don’t even notice it (tho they’re stoned like 90% of the time, so take it for what it’s worth).

Someone with zero knowledge would interpret those two perspectives very differently. Seattle’s “cloudy” reputation is probably a result of people from the SW US who are used to endless sunshine moving up there and being shell shocked. That doesn’t mean it’s *actually* cloudy 90% of time. But again, our brains are not objective sensors! 

[TT-SEA]

1 minute ago, Phil said:

Interesting how different our subjective interpretations can be. My family that moved from FL to WA describes it at the cloudiest place ever except for very sunny summers. But my older cousins that were born in Seattle don’t even notice it (tho they’re stoned like 90% of the time, so take it for what it’s worth).

Someone with zero knowledge would interpret those two perspectives very differently. Seattle’s “cloudy” reputation is probably a result of people from the SW US who are used to endless sunshine moving up there and being shell shocked. That doesn’t mean it’s cloudy 90% of time.

Anecdotal.    I know someone at work who moved from Texas years ago and they say that Seattle is way more sunny than its reputation would imply.    

[Deweydog]

I know someone who thought Patrick Duffy was the greatest actor who ever lived. RIP.

[TT-SEA]

3 minutes ago, Deweydog said:

I know someone who thought Patrick Duffy was the greatest actor who ever lived. RIP.

Pretty much a given... how can anyone deny this masterpiece?

[Phil]

10 minutes ago, TT-SEA said:

Anecdotal.    I know someone at work who moved from Texas years ago and they say that Seattle is way more sunny than its reputation would imply.    

That was my point. All these descriptions are anecdotal.

Which is why we have objective data from satellites and surface based radiation sensors. Because unlike our brains, they don’t lie. And what they reveal often conflicts with our subjective interpretations of reality.

Someone from Seattle might consider a day with fluffy cumulus mixed with clear sky & sunshine a “sunny” day. But someone from Phoenix might call it “intermittently cloudy”. In both cases skycover could be 30-40%, but it’s described entirely differently.

[Deweydog]

4 minutes ago, TT-SEA said:

Pretty much a given... how can anyone deny this masterpiece?

Premiered during a very warm/dry fall of 1991…

[SilverFallsAndrew]

10 minutes ago, Deweydog said:

I know someone who thought Patrick Duffy was the greatest actor who ever lived. RIP.

Wait WHAT?!

https://playbill.com/article/dallas-star-patrick-duffy-will-lead-u-k-tour-of-twelve-angry-men

[TT-SEA]

6 minutes ago, Phil said:

That was my point. All these descriptions are anecdotal.

Which is why we have objective data from satellites and surface based radiation sensors. Because unlike our brains, they don’t lie. And what they reveal often conflicts with our subjective interpretations of reality.

Someone from Seattle might consider a day with fluffy cumulus mixed with clear sky & sunshine a “sunny” day. But someone from Phoenix might call it “intermittently cloudy”. In both cases skycover could be 30-40%, but it’s described entirely differently.

Objectively... the F6 data says it was cloudy 40% of the time last month.    I can tell you 40% felt like it was sunny 95% of the time.   And most people in the Seattle area would likely agree with me.     

[TT-SEA]

2 minutes ago, SilverFallsAndrew said:

Wait WHAT?!

https://playbill.com/article/dallas-star-patrick-duffy-will-lead-u-k-tour-of-twelve-angry-men

I had to check as well... then assumed it was Matt just being Matt.  

[SilverFallsAndrew]

4 minutes ago, Deweydog said:

Premiered during a very warm/dry fall of 1991…

He's still alive BTW. 

[Port Angeles Foothiller]

1 hour ago, TT-SEA said:

Totally agree then.    But then it was sunny for 5 months straight after that period.

I loved every minute of it, although my yard and water bill hated it. I have to admit by October I was praying for rain.

[Phil]

Just now, TT-SEA said:

Objectively... the F6 data says it was cloudy 40% of the time last month.    I can tell you 40% felt like it was sunny 95% of the time.   And most people in the Seattle are would likely agree with me.     

You’re reading that incorrectly.

The F6 data says nothing about how many “cloudy days” there were. It merely indicates that overcast skies were observed at some point during a given day, even very briefly. Marine overcast that burns off by 8AM counts as a “cloudy” day.

When the F6 chart indicates thunderstorms, it doesn’t mean it was storming all day.  

[ChristheElohim]

4 minutes ago, SilverFallsAndrew said:

He's still alive BTW. 

Yeah I didn't see anything on him

[TT-SEA]

1 minute ago, Phil said:

You’re reading that incorrectly.

The F6 data says nothing about how many “cloudy days” there were. It merely indicates that overcast skies were observed at some point during a given day, even very briefly. Marine overcast that burns off by 8AM counts as a “cloudy” day.

When the F6 chart indicates thunderstorms, it doesn’t mean it was storming all day.  

It scores each day's sky cover on a scale of 0-10.     The average for the month was 4.   It might have technically been 40% but it felt like it was always sunny.  

[ChristheElohim]

Interesting https://phys.org/news/2023-07-surface-temperatures-simple-physics-due.amp

[TT-SEA]

As an example... the F6 data says 7/1/23 was cloudy 20% of the day.  

Here are the satellite images at 8 a.m., 11 a.m., 3 p.m., and 6 p.m.

[Phil]

22 minutes ago, TT-SEA said:

It scores each day's sky cover on a scale of 0-10.     The average for the month was 4.   It might have technically been 40% but it felt like it was always sunny.  

What I don’t know is whether that’s based on sensor data or hourly observations/etc. I assume that is either the 24hr average or average of the 24 hourly obs, and not simply the average during the daytime hours.

The DCA data has several days between 6-8 which could only be accurate if nighttime hours are included (nocturnal low level stratocumulus is common but it burns off very quickly in the AM).

 

[Phil]

1 minute ago, TT-SEA said:

As an example... the F6 data says 7/1/23 was cloudy 20% of the day.  

Here are the satellite images at 8 a.m., 11 a.m., 3 p.m., and 6 p.m.

 

 

 

 

Okay? There were probably low marine clouds before sunrise.

No, the SeaTac sensors are not mysteriously hypersensitive to clouds.

[Deweydog]

32 minutes ago, SilverFallsAndrew said:

He's still alive BTW. 

Ugh. Somehow I got him confused with Jeff Goldblum. RIP.

[Phil]

13 minutes ago, Phil said:

What I don’t know is whether that’s based on sensor data or hourly observations/etc. I assume that is either the 24hr average or average of the 24 hourly obs, and not simply the average during the daytime hours.

The DCA data has several days between 6-8 which could only be accurate if nighttime hours are included (nocturnal low level stratocumulus is common but it burns off very quickly in the AM).

 

Okay yeah it’s definitely the nocturnal low clouds. The days with 8-10 skycover always have “1” (fog/mist) listed as one of the wx conditions, which only happens at night.

[TT-SEA]

9 minutes ago, Phil said:

Okay? There were probably low marine clouds before sunrise.

No, the SeaTac sensors are not mysteriously hypersensitive to clouds.

There actually wasn't any low clouds before dawn that day.    The low clouds this summer have been coming in during the early morning for the most part so when its sunny in the early morning it was clear overnight.    I do notice some smoke in the morning on those images.   Maybe it picked up smoke as clouds?

[Tyler Mode]

Can we move the TT-SEA/Phil convo to a separate thread?

[Phil]

1 minute ago, TT-SEA said:

There actually wasn't any low clouds before dawn that day.    The low clouds this summer have been coming in during the early morning for the most part so when its sunny in the early morning it was clear overnight.    I do notice some smoke in the morning on those images.   Maybe it picked up smoke as clouds?

How would you know, you were asleep. BTW these 5min obs can be retrieved on WRCC website. Give me 5 mins.

[MossMan]

4 hours ago, TT-SEA said:

Hopefully the 12Z GFS is not teasing us.

Nothing over my house? Dump it!