James Jones

Were summers really drier back then? I don't see much evidence for that. If anything, it seems like our summers are slightly drier now than they used to be. SEA has had a couple of anomalously wet summer months the last few years but that has been isolated right around the Seattle area, it's been normal to the north and south. Our summers are obviously quite a bit warmer than they used to be though.

850s at 19C with light offshore flow, good enough to get it done. Marine push will probably come too late. Hard to tell without looking at the individual ensemble members, it could just have trouble figuring out the strength/location of the cutoff. The Canadian at 240 hours looks pretty similar to the Euro.

I think I've seen Andrew complain about dews in the mid 50s as being too humid before (probably gave Phil an aneurysm). Yesterday was perfect. Starting to feel a bit hot out there right now.

Any idea for September?

Vodka?

Fake cold episodes like the one we had in late December/early January are awesome. You can do a hell of a lot worse than sun with highs in the upper 30s, and as we saw, it can even help us along to snow.

Yeah, I find it interesting that some months have warmed so dramatically while others have seen essentially no change at all. I'd love to know why but I won't even pretend to have an explanation. It basically means that fall used to be a longer season here, with September being a legit fall month (these days it leans more towards summer) and the coldest month being January. Now things are more compressed, with fall being a quick crash from mid-late September through the end of November. Also amazing that February used to be as cold or colder than December, whereas now December is colder by a significant margin. Again, I don't know why things have shifted to such an early peak for winter, but it has. And the 1890s were indeed very cold. Even relative to its era, that decade stands out a lot more than the 1950s, at least in Portland.

Jim is actually right though, overall October hasn't warmed as much as other months have, and the late October 2003 cold snap was the start of an awesome 10 week stretch of weather. I have a graph of the per decade averages highs of the old downtown Portland station here: http://i.imgur.com/B1vt2P5.png?1 And PDX: http://i.imgur.com/HCCeeiL.png?1 I didn't bother getting the lows because the UHI environment changed too much over the life of these stations (which has some effect on the highs too of course).

Yeah. The average used on this graph is a bit cooler than the German one, and the ensemble mean is a bit warmer. Not sure why those differences are there.

For PDX I always use this site, the graph is just cleaner and easier to look at. The problem is that sometimes it's slow to update. http://weather.jimlittle.net/tools/ensemble_plots/images/06_z_gfs_ens.png(just change the 06 in the URL to 12, 18 or whatever for the other runs) http://i.imgur.com/ExHu5PX.png?1

We could do a monthly Tim/Phil thread for August, and an August 2016 PNW discussion thread as usual, and then have a "forecast contest" for which thread gets more posts.

Yep. Those of us who actually live here have noticed. Are there reliable averages for sky conditions at these stations? It'd be interesting to see how much this deviates from normal.

It's been a really long time since the region saw a legitimately cool August. 2000 was probably the last time, but even that was nothing impressive at all compared to many Augusts from the 1970s and earlier. I guess you could go with the "we're due" logic, but as we know weather doesn't really work that way.

A bit off topic, but Mitribah, Kuwait tied the planet's all time record high yesterday (aside from the dubious Death Valley reading in 1913): https://www.wunderground.com/blog/JeffMasters/eastern-hemispheres-alltime-temperature-record-kuwait-fries-in-54

Come on bro, this forum isn't for discussing weather in a reasonable manner. It's for Tim and Phil to bicker endlessly over utterly trivial nonsense that nobody else gives even the slightest **** about.

Can we do this now?

What maps showed that? This doesn't exactly scream below average: http://www.tropicaltidbits.com/analysis/models/ecmwf-ens/2016072100/ecmwf-ens_T850a_us_10.png http://www.tropicaltidbits.com/analysis/models/ecmwf-ens/2016072100/ecmwf-ens_z500a_us_10.png

Yep, definitely a crazy heat wave. I think 9/2/88 also has the warmest 850mb temps on record for the western lowlands, which makes sense because how else would you get that warm in early September? http://i.imgur.com/8jBzKot.png http://i.imgur.com/vQ6HyOd.png?1

Just adding to this, nearly every every day from July 10 through August 17 has a record high of 100+ at PDX with a pronounced dropoff from the 18th on with only a few scattered 100+ days here and there. SEA shows the same thing, with nearly every day from the 2nd week of July until August 17th with a record high in the mid 90s or higher, but they're much rarer from the 18th onwards. Also it's an odd quirk of history that PDX has never hit 100 during the first 3 days of August, considering that's basically the absolute peak of our summer climo. The only other days in that 7/10 to 8/17 stretch that have failed to hit 100 are 7/22 and 7/26.

18Z is sure a warm run, not really a major heat wave but just solidly above normal from Sunday onwards. Supports Phil's call of a ridgy period in early August. Hoping the models trend towards a quick spike of heat followed by a crash or a return to more normal conditions.

Yep, gorgeous day. Clear skies, 80 degrees, 50 degree dew, and a light breeze is total summer perfection in my book.

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.

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.

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.

Impressive lack of diurnal range at PDX so far this month, just a 17 degree difference between the average high and low. Though that looks to change with the upcoming pattern.