July 2019 Weather Discussion for the PNW

[BLI snowman]

That is incredible. In February 2014, PDX only got up to 23 one day. Never before had a high been that low since records were taken.

 

On that date.

 

PDX's all time record lowest high is 14 on 12/30/1968.

 

Downtown Portland's record lowest is 9 on 1/15/1888.

[BLI snowman]

The Blob is back and so are warm lows...hmmmmmm.

 

I don't think the warm lows ever went away.

[Frontal Snowsquall]

On that date.

 

PDX's all time record lowest high is 14 on 12/30/1968.

 

Downtown Portland's record lowest is 9 on 1/15/1888.

Yeah, forgot to mention that late in the season (February).

[TigerWoodsLibido]

On that date.

 

PDX's all time record lowest high is 14 on 12/30/1968.

 

Downtown Portland's record lowest is 9 on 1/15/1888.

 

Man 68-69 was a behemoth.  Would love to have experienced that set of events. Regional bomb of snowstorms.

[Frontal Snowsquall]

New 7 day from KPTV. Would be awesome timing to get another sunny weekend.

 

You could say we overachieved today. High temperatures so far today. Doesn't say here but SEA got to 80. PDX currently with a +4 departure on the day.

 

[Front Ranger]

I don't think the warm lows ever went away.

Seemed like they weren't as prevalent the past couple summers.

[TT-SEA]

You could say we overachieved today. High temperatures so far today. Doesn't say here but SEA got to 80. PDX currently with a +4 departure on the day.

 

http://lmgcorporate.com/kptv/weather/web_ORWA_HIGHS_Today_West.jpg

 

 

 

Pretty nice for a troughing and colder than normal 850mb temps.  

[BLI snowman]

Seemed like they weren't as prevalent the past couple summers.

 

July 2013 was the last month God recorded a below average mean minimum in the summer.

[Front Ranger]

July 2013 was the last month God recorded a below average mean minimum in the summer.

 

July 2017 was below the 1981-2010 average. As was June 2018.

 

And the last two Julys had average lows easily cooler than the 2014-16 period. That was definitely the peak of the warm summer lows.

[Front Ranger]

Dec 2009 actually featured OLM's coldest average low for December on record, with an average of 25. Huh.

 

And March 2019 also set a record for coldest average low with 28.39. 

 

Amazing things are possible without UHI.

[Timmy]

On that date.

 

PDX's all time record lowest high is 14 on 12/30/1968.

 

Downtown Portland's record lowest is 9 on 1/15/1888.

Lots of questionable historical data being thrown out there lately. I knew that had to be wrong.

[Phil]

I see. Yeah, you need to fit around their schedule since you're the guest.

 

Yeah, I was looking at weather spark and for Bethesda, the most humid day of the year there is July 29. Looks like you might get some relief end of September.

 

"The muggier period of the year lasts for 4.1 months, from May 24 to September 27, during which time the comfort level is muggy, oppressive, or miserable at least 16% of the time. The muggiest day of the year is July 29, with muggy conditions 66% of the time.

 

The least muggy day of the year is February 19, when muggy conditions are essentially unheard of."

 

https://weatherspark.com/y/21013/Average-Weather-in-Bethesda-Maryland-United-States-Year-Round

And my my birthday is on July 28th. Figures, lol.

 

That data seems pretty close, though it looks like it was taken from Gaithersburg Apt, since our average high peaks at 90*F, not 87*F, and the average low bottoms out at 23*F, not 27*F.

 

Temps do peak in late July but dewpoints seem to max out in August. Definitely the least amount of variability during the August/September period..very stagnant minus any tropical systems.

[TacomaWaWx]

High temp of 77 so far today.

[Guest CulverJosh]

Its July 16th. Onshore flow will bring 80s (has the potential to bring 80s), to anywhere east of the coast range foothills outside of the higher terrain of the cascades. Why do you guys keep being surprised?

[Frontal Snowsquall]

Pretty nice for a troughing and colder than normal 850mb temps.

Definitely, that's what makes it even better. That's what I love about weather, there's so many other variables at play that affect surface temperature. Not just 850mb temperatures.

[Frontal Snowsquall]

And my my birthday is on July 28th. Figures, lol.

 

That data seems pretty close, though it looks like it was taken from Gaithersburg Apt, since our average high peaks at 90*F, not 87*F, and the average low bottoms out at 23*F, not 27*F.

 

Temps do peak in late July but dewpoints seem to max out in August. Definitely the least amount of variability during the August/September period..very stagnant minus any tropical systems.

I figured that most locations pull their information from the nearest airport since you can pretty much look at the stats on any US city. I really love the website, I've learned a lot about the climates of different cities. They also got a feature where it tells you which far away city has the closest temperature profile to yours. Very informative website.

[TacomaWaWx]

Looks like the high temp today will be 77. Currently 73 with a cool SW breeze.

[BLI snowman]

July 2017 was below the 1981-2010 average. As was June 2018.

 

And the last two Julys had average lows easily cooler than the 2014-16 period. That was definitely the peak of the warm summer lows.

 

 

2013 and 2014 were probably the peak, owing to the abundance of humid southerly flow in those two summers. I don't think the SSTAs had as much to do with it.

[Frontal Snowsquall]

[Front Ranger]

2013 and 2014 were probably the peak, owing to the abundance of humid southerly flow in those two summers. I don't think the SSTAs had as much to do with it.

 

Aug/Sep 2013 were certainly impressive in that respect. OLM set its record for warmest average low in September that year.

 

But summer 2015 was crazy for how many really warm lows occurred. 8 lows of 66+ at PDX, including the two warmest lows in June history.

[Frontal Snowsquall]

[Dave]

Of course I was in Texas during the wonderful early Dec 2013 event, where Eugene had some snow and tied their all-time low of -10F.

 

There were some coastal communities who also set their all-time lows. Folks that worked with me at the Pelican in Pacific City said they were in the negatives with snowcover.

We had 6 inches in dec 2013. It remained intact on the roads for 6 days. Eugene's all time record low is -12. -10 is second place. Ironically they both occurred on the same date, so the -10 didn't even set a record.

[Phil]

The blob is overrated.

[TigerWoodsLibido]

We had 6 inches in dec 2013. It remained intact on the roads for 6 days. Eugene's all time record low is -12. -10 is second place. Ironically they both occurred on the same date, so the -10 didn't even set a record.

Couldn’t beat out the 1972 event. My mom tells me stories about that one. Over a foot of snow with big drifts and temps plummeting way into the negatives.

[Phil]

I might eat crow for this later, but the way the GFS is handling that ULL seems bizarre to me. I haven’t seen one reverse and move NW at that latitude/location before.

[TT-SEA]

I might eat crow for this later, but the way the GFS is handling that ULL seems bizarre to me. I haven’t seen one reverse and move NW at that latitude/location before.

Not really bizarre. Its gets picked by another ULL and is shunted to the NE as they hit the wall of ridging across the West.

 

ULLs have been spinning around us for the last month as they hit the ridging wall in the middle of the country.

[Deweydog]

ULL’s usually just come barreling right toward and over us in late July.

 

#weirdyear

[Phil]

Not really bizarre. Its gets picked by another ULL and is shunted to the NE as they hit the wall of ridging across the West.

 

ULLs have been spinning around us for the last month as they hit the ridging wall in the middle of the country.

Not really..at that latitude there should be some forward progression given antecedent conditions.

 

This entire wavetrain looks strangely oblong to me. Again, we’ll see, but I’m scratching my head as to what would produce such constipation.

 

[TT-SEA]

The old GFS is even more emphatic than the new GFS with ridging next week.

 

The GEM is coming around as well... shifted westward with each run.

[TacomaWaWx]

No power in my neighborhood in North Tacoma for the last 20 minutes or so. I can see it’s on in NE Tacoma and other places so it’s localized. It is a little breezy and cool here this evening but I don’t think they’re related lol.

[Phil]

The old GFS is even more emphatic than the new GFS with ridging next week.

 

The GEM is coming around as well... shifted westward with each run.

The way the GEM goes about it makes sense, though.

 

That GFS solution is all kinds of stupid.

[Omegaraptor]

The way the GEM goes about it makes sense, though.

That GFS solution is all kinds of stupid.

GFS has the eastern trough digging all the way down to the Tropic of Cancer. Is that normal?

[TT-SEA]

The way the GEM goes about it makes sense, though.

 

That GFS solution is all kinds of stupid.

The GEM literally has a ULL moving NW and away from us for 4 straight days. How is that not strange but the GFS is stupid?

[Phil]

Even the weird-looking GFS wavetrain delivers a result that is much closer to normal @ 850mb in the D9-16 period.

 

I’ll just have to activate my weather manipulation device to kill off that ridge when I’m there.

 

[Phil]

The GEM literally has a ULL moving NW and away from us for 4 straight days. How is that not strange but the GFS is stupid?

Because there’s sufficient AAM removal upstream and propagation from the correct latitude on the GEM, from what I can see.

[TT-SEA]

Even the weird-looking GFS wavetrain delivers a result that is much closer to normal @ 850mb in the D9-16 period.

 

I’ll just have to activate my weather manipulation device to kill off that ridge when I’m there.

 

With that pattern... below normal 850mb temps would still be a little above normal at the surface. See today.

 

But we all dread our summer ridges with the usual 80-degree dewpoints. Ridging leads to suffocating humidity here. Our climate is exactly like your climate. You are right to assume its exactly the same and be very afraid of anything but a deep trough.

[TT-SEA]

Phil spends all this time cheering for a trough for the 3 days that he is in Everett.

 

Meanwhile... Everett is usually around 72 degrees under a trough in late July and maybe 80 under a ridge. With dewpoints in the 40s or 50s either way.

 

The implications are obviously huge!

[Phil]

GFS has the eastern trough digging all the way down to the Tropic of Cancer. Is that normal?

Haha, no. Nearly impossible for that to happen without it cutting off into a ULL.

 

Getting a full latitude trough down there can be difficult in the middle of winter. It ain’t happening in July (though it would be totally awesome if it could, lol).

[TT-SEA]

Haha, no. Nearly impossible for that to happen without it cutting off into a ULL.

 

Getting a full latitude trough down there can be difficult in the middle of winter. It ain’t happening in July (though it would be totally awesome if it could, lol).

This is the deepest point of the trough.

 

I just want to get you on record saying that is a laughably impossible pattern for July.

 

[Phil]

With that pattern... below normal 850mb temps would still be a little above normal at the surface. See today.

 

But we all dread our summer ridges with the usual 80-degree dewpoints. Ridging leads to suffocating humidity here. Our climate is exactly like your climate. You are right to assume its exactly the same and be very afraid of anything but a deep trough.

Still room for it to trend cooler. I’m negotiating with Mother Nature right now, ready to accept a swampy September in exchange for a super duper PNW vortex starting 8/1.

 

The aggregate of convectuve forcing will become EHEM centered with time, so there’s a chance that troughing comes back sooner than we think!