August 2023 Weather in the PNW

[Omegaraptor]

1 hour ago, Gradient Keeper said:

Let's do the Winter version of this heatwave something like 5-7 days with high temps in the 10s and 20s.

A high of 115 is probably easier to achieve than a high of 15 at PDX now

[Phil]

1 hour ago, Timmy Supercell said:

Yeah part of the reason I haven't gone into much photos/video lately is because of the kinds of streets we have here. If I wasn't so worried about becoming a lightning rod I'd stand in the middle of Central Park for sky shots.

Haha, yep same vibes. Unless I’m drunk there’s no way I’m standing outside in a bonafide lightning barrage.

[Phil]

51 minutes ago, Timmy Supercell said:

We better get our storms during or towards the end of this upcoming heatwave. Not looking forward to more lows in the 70's and the sun is out for days and days.. The 10-day on wunderground here has no thunder on it, and that's the first time this summer that's happened. July seems to be the most convective month this year, I think August last year won over that spot by a smidge. 

If there has to be a ridge, ideally you want to flirt with the edge of it without ended up under it. Otherwise you’ll be lucky to see a cloud let alone a storm.

I vastly prefer deep 500mb troughs since that’s where you get the shear and long lived updrafts. Ring of fire patterns are all WAA/speed shear which can work but also had high bust potential.

 

[SilverFallsAndrew]

13 minutes ago, Dave said:

Looks like the overtime low was around 69/70 at EUG, according to the 5 min obs. Low hanging fruit, but I believe that is good enough for the 2nd warmest low of all time. If the sensor was in downtown Eugene, that would obviously be a much different story.

Obviously due to ocean temps being in the 60s 70 miles away. Nothing to do with cloud cover after a high of 105.

[TacomaWx]

9 minutes ago, TT-SEA said:

This summer is pretty good evidence for SSTAs having some impact.    We had colder than normal water offshore in June and July and then it completely flipped to anomalously warm at the end of July so we had both in the same summer.  

In June and July... SEA had just 4 days with lows at 60+.  

Since August 1st there have been 14 lows at 60+ which includes a troughy period as well.  

I don't think that is entirely coincidental.   

Yeah it does make a lot of sense. You’d think it would lead to other effects like an increased marine layer, or warmer daytime highs. Not sure SSTs have much of an impact on either of those things though. 

[Ken in Wood Village]

Looks like there could be some beneficial rain for the forecast fires south of my area. That's if you believe what the radar is showing. 

[TacomaWx]

2 minutes ago, SilverFallsAndrew said:

Obviously due to ocean temps being in the 60s 70 miles away. Nothing to do with cloud cover after a high of 105.

There’s definitely some situations where cloud cover, UHI and other things can explain warm overnight lows. I don’t think Tim’s logic on SSTs is unsound though. It does make sense but sometimes there’s other factors to consider as well. 

[TT-SEA]

1 minute ago, TacomaWx said:

Yeah it does make a lot of sense. You’d think it would lead to other effects like an increased marine layer, or warmer daytime highs. Not sure SSTs have much of an impact on either of those things though. 

My take is that warmer SSTAs offshore reduces marine layer clouds overall (all else being equal) and weakens the strength of marine pushes and makes the low level air mass a little warmer on the west side of the Cascades.    I think it has the biggest impact on overnight lows but probably increases daytime temps indirectly with less marine layer clouds to burn off (weaker inversions) allowing for better heating.

[TT-SEA]

5 minutes ago, SilverFallsAndrew said:

Obviously due to ocean temps being in the 60s 70 miles away. Nothing to do with cloud cover after a high of 105.

There are many variables Andrew.     What you described is another variable that can make for warm nights.   Its much more nuanced of course.  What we are saying also appears to be a factor up here.  

[ShawniganLake]

This forest fire season in BC will likely surpass 4 million acres burned by later today.  The fire behaviour in the southern interior should be pretty dangerous this afternoon as that dry cold front drops through.  

[SilverFallsAndrew]

2 minutes ago, TacomaWx said:

There’s definitely some situations where cloud cover, UHI and other things can explain warm overnight lows. I don’t think Tim’s logic on SSTs is unsound though. It does make sense but sometimes there’s other factors to consider as well. 

Yeah it could have something to do with it. We should also take a look at lows east of the cascades. 

[TT-SEA]

Just now, ShawniganLake said:

This forest fire season in BC will likely surpass 4 million acres burned by later today.  The fire behaviour in the southern interior should be pretty dangerous this afternoon as that dry cold front drops through.  

This afternoon looks potentially explosive east of the Cascades.  

[Rubus Leucodermis]

Overnight min of 63.0˚F. Now 71.4˚F.

[Dave]

9 minutes ago, SilverFallsAndrew said:

Obviously due to ocean temps being in the 60s 70 miles away. Nothing to do with cloud cover after a high of 105.

I think there might even be some 70+ ocean temps out there.  But yes, some cloud cover moved in. Air quality is much better this morning as well.

[SilverFallsAndrew]

3 minutes ago, TT-SEA said:

My take is that warmer SSTAs offshore reduces marine layer clouds overall (all else being equal) and weakens the strength of marine pushes and makes the low level air mass a little warmer on the west side of the Cascades.    I think it has the biggest impact on overnight lows but probably increases daytime temps indirectly with less marine layer clouds to burn off (weaker inversions) allowing for better heating.

Aren’t mariners layers pretty common in Southern California? Their ocean temps are quite a bit warmer than ours.

[TT-SEA]

8 minutes ago, SilverFallsAndrew said:

Aren’t mariners layers pretty common in Southern California? Their ocean temps are quite a bit warmer than ours.

And they have extreme desert heat to the east creating a stronger low level gradient.  

I just know that when the water is really warm off our coast (compared to normal)... chilly minimums will be much more rare on the west side.   At least up here.

[Timmy Supercell]

26 minutes ago, Phil said:

Haha, yep same vibes. Unless I’m drunk there’s no way I’m standing outside in a bonafide lightning barrage.

The park here does have one of those small round gazebos, I could maybe stand under its roof as long as there's not a bunch of annoying wind that comes with a storm. Not getting my camera soaked like I did once or twice in K-Falls. 

[Phishy Wx]

Fire situation is pretty scary over here today, expecting 30mph gusts later and 100 degrees.  I have a bad feeling

[BLI snowman]

"Chilly" minimums haven't really been a thing here in the summer for decades.

[Meatyorologist]

Ozette. Super weird temp profile in this area. It was absurdly muggy during the hike toward the beach, something like a 95/75 spread. This is with a swamplike terrain and vividly green marshland. Felt like Louisiana again.

Then you hit the marine air right on the coast and the temperatures drop into the 60s with a persistent haze and a stiff breeze. Pretty fascinating gradient to behold.

[LowerGarfield]

1 hour ago, Cloud said:

An impressive heatwave but the end is near. Got some dews forming on cars when leaving work this morning. Only means it was a bit cooler morning compared to the last 3 mornings. Can also feel it! 

Even out here, I noticed that. Went to sleep and had to put a shirt on later in the night. Then was a bit too cold after that. Tomorrow will still be warm at my location but high 80's with a low in 50's is much more tolerable than 100/mid 70's.

[TT-SEA]

6 minutes ago, BLI snowman said:

"Chilly" minimums haven't really been a thing here in the summer for decades.

Lots of people were reporting lows in the 40s in June and July.   Tyler was doing so quite frequently as an example.   

You can just blanket say summer is always warm now and of course there is general warming happening regardless of the SSTAs and that is a dominant factor.   But I believe this summer provides some evidence of the nuances of warmer and colder than normal SSTAs off our coast having an impact on the weather farther inland.  

[SilverFallsAndrew]

4 minutes ago, BLI snowman said:

"Chilly" minimums haven't really been a thing here in the summer for decades.

Thank you. 

[TT-SEA]

2 minutes ago, SilverFallsAndrew said:

Thank you. 

Too simplified and lacking nuance.  See above.   

[SilverFallsAndrew]

I'm just saying, I think a lot of people are looking at pretty colors on a map and not realizing just how cold the ocean temps still are... The water off Garibaldi is currently 7.5F above normal, but its still only 62.6F. Charleston Oregon is about 2.5F above normal, but their ocean temp is currently 55.8. 

[TT-SEA]

Just now, SilverFallsAndrew said:

I'm just saying, I think a lot of people are looking at pretty colors on a map and not realizing just how cold the ocean temps still are... The water off Garibaldi is currently 7.5F above normal, but its still only 62.6F. Charleston Oregon is about 2.5F above normal, but their ocean temp is currently 55.8. 

I am saying it's all relative compared to our averages.     Warmer than normal is still warmer than normal even if it's still cold relatively speaking.

[Phil]

8 minutes ago, TT-SEA said:

Lots of people were reporting lows in the 40s in June and July.   Tyler was doing so quite frequently as an example.   

You can just blanket say summer is always warm now and of course there is general warming happening regardless of the SSTAs and that is a dominant factor.   But I believe this summer provides some evidence of the nuances of warmer and colder than normal SSTAs off our coast having an impact on the weather farther inland.  

Puget Sound temps are likely to be astronomically more important than Pacific SSTs. The depth of the marine layer is often below the peaks of the Olympics, and low level/BL advection isn’t exactly strong in the summer.

It’s more likely the warm/dry pattern warmed Puget Sound water temperatures sufficiently to warm the marine inversion/BL.

[SilverFallsAndrew]

 

Just now, TT-SEA said:

I am saying it's all relative compared to our averages.     Warmer than normal is still warmer than normal even if it's still cold relatively speaking.

Yeah true. But the land temps have warmed correspondingly, so IMO that doesn't explain the lack of marine layer, you could make a better argument for marine layer days being correspondingly warmer, I don't think it explains the absence of the marine layer though. 

 

[TacomaWx]

Just now, Phil said:

Puget Sound temps are likely to be astronomically more important than Pacific SSTs. The depth of the marine layer is often below the peaks of the Olympics, and low level/BL advection isn’t exactly strong in the summer.

It’s more likely the warm/dry pattern warmer Puget Sound water temperatures enough to warm the marine inversion/BL.

I was thinking about the Puget sound temperatures as well earlier. They definitely peak in warmth in august/September which could be a factor too. 

[SilverFallsAndrew]

Just now, Phil said:

Puget Sound temps are likely to be astronomically more important than Pacific SSTs. The depth of the marine layer is often below the peaks of the Olympics, and low level/BL advection isn’t exactly strong in the summer.

It’s more likely the warm/dry pattern warmed Puget Sound water temperatures sufficiently to warm the marine inversion/BL.

According to the numbers I'm looking at Port Angeles water temps are about 1F below normal, Tacoma +1F, and Friday Harbor is +2.3F. 

[TT-SEA]

1 minute ago, Phil said:

Puget Sound temps are likely to be astronomically more important than Pacific SSTs. The depth of the marine layer is often below the peaks of the Olympics, and low level/BL advection isn’t exactly strong in the summer.

It’s more likely the warm/dry pattern warmer Puget Sound water temperatures enough to warm the marine inversion/BL.

I think the SSTAs offshore have some impact all the way to the Cascade foothills in the summer.    It might not be a dominant factor but it is present.    

[Phil]

Just now, TacomaWx said:

I was thinking about the Puget sound temperatures as well earlier. They definitely peak in warmth in august/September which could be a factor too. 

It’s definitely a factor. Probably “the” factor. Especially because they’re significantly warmer than pacific SSTAs

I actually agree with Andrew for once lol.

[YahRaEl]

This was from Cliff Mass in 2020 increased warmth at night and slightly more humid when waters off the coast are warmer.

[Cascadia_Wx]

Clouds. Low of 68 here, currently 71.

[TT-SEA]

Just now, SilverFallsAndrew said:

According to the numbers I'm looking at Port Angeles water temps are about 1F below normal, Tacoma +1F, and Friday Harbor is +2.3F. 

The Strait is different than the south Sound.   I don't think SSTAs in the central and south Sound have much of an impact on local weather unless you are on the shoreline.    The strength of marine pushes through the Chehalis Gap and the Strait are much more impactful to our local weather up here.    

[Phil]

Just now, TT-SEA said:

I think the SSTAs offshore have some impact all the way to the Cascade foothills in the summer.    It might not be a dominant factor but it is present.    

The pattern that produced the warm NE-Pacific SSTAs is associated with reduced marine influence/less onshore flow.

That subsequently warmed Puget Sound which inhibits the marine inversion from propagating farther inland (erodes inversion since sound is significantly warmer than the Pacific).

Correlation, not causation.

[Phil]

1 minute ago, ChristheElohim said:

This was from Cliff Mass in 2020 increased warmth at night and slightly more humid when waters off the coast are warmer.

That’s an insufficient analysis, though.

The NE-Pacific SST warming is driven by the same pattern that reduces marine influence over the Puget Sound region, which leads to warming of those waters, which given speed of low level/BL winds, must be astronomically more important to BL/surface temps.

[TT-SEA]

3 minutes ago, Phil said:

The pattern that produced the warm NE-Pacific SSTAs is associated with reduced marine influence/less onshore flow.

That subsequently warmed Puget Sound which inhibits the marine inversion from propagating farther inland (erodes inversion since sound is significantly warmer than the Pacific).

Correlation, not causation.

Yes... you can go back to what caused the water to warm and it had to be related to the upper level pattern.   But once the warmer than normal water is in place... it tends to lead to warmer temps overall locally all else being equal.   Obviously a strong upper level trough will still overwhelm any impact of the SSTAs offshore.

[Cascadia_Wx]

Is the writer’s strike affecting the forum too? This seems like a re run.

[Front Ranger]

7 minutes ago, Phil said:

It’s definitely a factor. Probably “the” factor. Especially because they’re significantly warmer than pacific SSTAs

I actually agree with Andrew for once lol.

Nah, it's not just areas near Puget Sound that have seen warner lows once the SSTAs warmed.