September 2015 in the Pacific Northwest

[TT-SEA]

12z euro still going with it.

image.gif

Yep... it's going to happen. ECMWF is too adamant.

 

Just checked the detailed map from the 12Z ECMWF and it's sunny for most of the region by Saturday afternoon and in the upper 60s. So it still could be a very nice weekend. The rain comes through quickly on Friday night.

[TT-SEA]

Full 12Z ECMWF run is great.

 

Sunday has the potential to be really nice... sunny and well into the 70s (near 80 around PDX). And then just a continuation of ridging all of next week.

[SilverFallsAndrew]

Already 80 at PDX. 

[TT-SEA]

Already 80 at PDX. 

 

 

Gorgeous day here... but I am jealous of PDX.

[ShawniganLake]

Gorgeous day here... but I am jealous of PDX.

How are PDX and Seattle looking for the month. Either of them going to pull out a below average September?

[Deweydog]

Upsetting out there!

[TT-SEA]

How are PDX and Seattle looking for the month. Either of them going to pull out a below average September?

 

 

SEA will be slightly below normal... PDX will be a little above normal.

 

Basically a normal September overall for temperature... a little drier than normal as well.  

[Phil]

Battle between the GEFS and EPS in the medium/long range. Hopefully the latter verifies.

[TT-SEA]

Battle between the GEFS and EPS in the medium/long range. Hopefully the latter verifies.

 

 

The ECMWF is warmer in the medium / long range for the PNW.   

 

http://old.ecmwf.int/products/forecasts/d/getchart/catalog/products/forecasts/medium/deterministic/msl_uv850_z500!Geopotential%20500%20hPa%20and%20Temperature%20at%20850%20hPa!240!North%20America!pop!od!oper!public_plots!2015092812!!chart.gif

 

18Z GFS now has some rain on Sunday while the ECMWF shows 80 degrees and sunny.    

[Jesse]

How are PDX and Seattle looking for the month. Either of them going to pull out a below average September?

Below average month isn't in the cards for PDX now.

[Jesse]

Upsetting out there!

As long as you're enjoying it!

 

I'm done really caring. Clearly we will never see a below average month ever again.

[Phil]

The ECMWF is warmer in the medium / long range for the PNW.

 

18Z GFS now has some rain on Sunday while the ECMWF shows 80 degrees and sunny.

The EPS mean is much colder than the GEFS mean.

 

The operational 18z GFS doesn't even break the wave into Alaska/depicts a destructive interference pattern. You can already see that it's heading in an ugly direction..one that will probably lead to a large GOA vortex and warm rain on W/SW flow.

[TT-SEA]

The EPS mean is much colder than the GEFS mean.

 

The operational 18z GFS doesn't even break the wave into Alaska/depicts a destructive interference pattern. You can already see that it's heading in an ugly direction..one that will probably lead to a large GOA vortex and warm rain on W/SW flow.

 

 

ECMWF ensemble mean looks fairly benign with some ridging in the long range:

 

http://old.ecmwf.int/products/forecasts/d/getchart/catalog/products/forecasts/medium/eps/ensm/essential!Geopotential%20at%20500hPa!North%20America!240!pop!od!enfo!plot_ensm_essential!2015092812!!chart.gif

[Phil]

ECMWF ensemble mean looks fairly benign with some ridging in the long range

 

The EPS has offshore vorticity much farther west in the 11-15 day range, allowing for a sharper ridge into Alaska/retrogression potential w/ northerly flow aloft. The GEFS puts a giant vortex in the GOA, flooding the region w/ SW flow.

[westcoastexpat]

As long as you're enjoying it!

 

I'm done really caring. Clearly we will never see a bellow average month ever again.

 

Poor thing  

[bainbridgekid]

The ECMWF is warmer in the medium / long range for the PNW.   

 

http://old.ecmwf.int/products/forecasts/d/getchart/catalog/products/forecasts/medium/deterministic/msl_uv850_z500!Geopotential%20500%20hPa%20and%20Temperature%20at%20850%20hPa!240!North%20America!pop!od!oper!public_plots!2015092812!!chart.gif

 

18Z GFS now has some rain on Sunday while the ECMWF shows 80 degrees and sunny.    

Looks cold in Northern Canada.

[Tyler Mode]

Days 5 and 6 in Alaska (September 13th+14th, 2015)

Pictures in this gallery from my drive to Chena Hot Springs from Copper Center.  The weather started out beautifully clear then turned cloudy and somewhat snowy.

https://weathercrazy.smugmug.com/Landscapes/Alaska-Days-5-and-6-2015

 

[Black Hole]

ECMWF weeklies that came out today look warm and dry for the core of October. Hints of a pattern shift towards the end of the month but that's a long way out. CFS has been showing this for a while though so I guess the slow start to real fall weather we have seen in recent years will continue.

[Jesse]

ECMWF weeklies that came out today look warm and dry for the core of October. Hints of a pattern shift towards the end of the month but that's a long way out. CFS has been showing this for a while though so I guess the slow start to real fall weather we have seen in recent years will continue.

Sad news.

[TT-SEA]

ECMWF weeklies that came out today look warm and dry for the core of October. Hints of a pattern shift towards the end of the month but that's a long way out. CFS has been showing this for a while though so I guess the slow start to real fall weather we have seen in recent years will continue.

 

 

Happy news.      Pretty typical it seems of a strong Nino.   

[Jesse]

Looks like the 00z GFS is trending more toward the Euro/Canadian.

[Front Ranger]

Happy news.      Pretty typical it seems of a strong Nino.   

 

Strong Ninos have featured some pretty impressive cold events for the West in October.

[TT-SEA]

Strong Ninos have featured some pretty impressive cold events for the West in October.

 

 

Maybe later in the month? 

 

1972 and 1986 had no rain at all here in the foothills until the 3rd week of the month.    I guess 1997 was pretty wet in October.

[TT-SEA]

00Z Canadian sticks to the ULL scenario for Friday night/Saturday morning.     Most of the weekend ends up nice.  

 

That seems to be a good thing overall... it blocks up the pattern more next week and results in a longer period of nice weather.

[ShawniganLake]

Maybe later in the month?

 

1972 and 1986 had no rain at all here in the foothills until the 3rd week of the month. I guess 1997 was pretty wet in October.

I think 1986 was technically moderate. As far as warmth goes in strong ninos it's limited, at shawnigan lake at least. 65 had a warm October but 57, 72, 82, 97 were average to below.

 

For moderate ninos, it's a 50/50 split for October temps. 63, 86, 87 mild. 91, 02, 09 cool.

[Front Ranger]

Maybe later in the month? 

 

1972 and 1986 had no rain at all here in the foothills until the 3rd week of the month.    I guess 1997 was pretty wet in October.

 

All over the month. 2009, 1997, 1982, 1972, and 1957 all had significant cool and/or troughy periods for much of the West in the first half of the month. The good news for you is that several of them were relatively dry for the PNW.

 

How wet it was at your particular location in the West is another matter, but I don't think that's what Black Hole was talking about with the Euro weeklies in mind.

[TT-SEA]

ECMWF has not wavered at all with the ULL solution... GFS still has not caught on.   

 

Looks like a great weekend per the 00Z ECMWF... that ULL is all the way down in SoCal by Sunday.  

 

http://old.ecmwf.int/products/forecasts/d/getchart/catalog/products/forecasts/medium/deterministic/msl_uv850_z500!Geopotential%20500%20hPa%20and%20Temperature%20at%20850%20hPa!120!North%20America!pop!od!oper!public_plots!2015092900!!chart.gif

http://old.ecmwf.int/products/forecasts/d/getchart/catalog/products/forecasts/medium/deterministic/msl_uv850_z500!Geopotential%20500%20hPa%20and%20Temperature%20at%20850%20hPa!144!North%20America!pop!od!oper!public_plots!2015092900!!chart.gif

[TT-SEA]

And the GFS just came around on the 12Z run. The ULL scenario is better for nicer weather afterwards.

[Jesse]

The GFS finally caved.

 

What I like about the solutions that show the ULL is that its passage seems to keep the really warm weather at bay for the first week of October. Runs without the ULL had the offshore ridge build directly over us next week, while runs with the ULL keep it mostly offshore.

[TT-SEA]

Probably 80 at PDX on Sunday with the ULL scenario. Warmer than earlier GFS solutions.

[BLI snowman]

Probably 80 at PDX on Sunday with the ULL scenario. Warmer than earlier GFS solutions.

 

Not really, the 12z yesterday was showing 86 on Sunday at PDX.

 

http://wxweb.meteostar.com/sample/sample.shtml?run=2015092812&text=KPDX

[TT-SEA]

Not really, the 12z yesterday was showing 86 on Sunday at PDX.

 

http://wxweb.meteostar.com/sample/sample.shtml?run=2015092812&text=KPDX

 

The 18Z GFS from yesterday showed showers for Sunday.

[TT-SEA]

And now the 12Z Canadian has abandoned the ULL solution.  Pretty good chance the 12Z ECMWF follows suit based on model behavior in the past.  

 

http://img.meteocentre.com/models/gemglb_amer_12/GZ_D5_PN_108_0000.gif

http://img.meteocentre.com/models/gemglb_amer_12/GZ_D5_PN_132_0000.gif

[TT-SEA]

12Z Canadian is a thing of beauty for the entire run.    Maybe some snow in northern MN next week and a nice stretch of warm weather out here on that run.

 

http://img.meteocentre.com/models/gemglb_amer_12/GZ_D5_PN_240_0000.gif

[BLI snowman]

The 18Z GFS from yesterday showed showers for Sunday.

 

Moral of that story being the GFS is a total mess and should never be taken seriously again.

[Jesse]

Moral of that story being the GFS is a total mess and should never be taken seriously again.

 

It's been a pretty pathetic performance this week. Seeing the Canadian and EURO pick up on the ULL solution days ago and the GFS just now starting to come around kind of puts it to shame.

[TT-SEA]

It would not surprise me to see all the models completely change their solutions this morning.

 

GFS went one way... Canadian jumped another way.    ECMWF up next.  

[Front Ranger]

LOL models.

[Jesse]

12Z GFS ensembles suddenly aren't looking so ridgetastic.

 

[Jesse]

Lots of wet ensemble members in the LR. That would be nice.