September 2015 in the Pacific Northwest

[GHweatherChris]

I'm thinking mild/wet November with our best chance for snow in mid to late January. January has completely sucked too much recently for it to continue much longer.

If I take my gut out of it, I tend to agree with you.

 

But for some reason this has a Thanksgivingish feel to it for western cold and snow and then again in February.

 

Scientifically, who knows though....

[TT-SEA]

If I take my gut out of it, I tend to agree with you.

 

But for some reason this has a Thanksgivingish feel to it for western cold and snow and then again in February.

 

Scientifically, who knows though....

 

 

Thanksgiving weekend last year was awesome here.   Not too common though.   Doubt it happens two years in a row.   This was 11/29/14 out here:

 

http://s28.postimg.org/uvpjf5kcd/Snow_SS.jpg

[richard mann]

I love the Canadian model.   

 

 

http://img.meteocentre.com/models/gemglb_amer_00/GZ_D5_PN_192_0000.gif

 

How 'bout we try this tack Tim. ...

 

"Hate it."

[richard mann]

Jim's around. We PM back and forth a few times a week.

 

.. Could be a decent "Snow" season ahead, I'm thinking.

[BLI snowman]

If I take my gut out of it, I tend to agree with you.

 

But for some reason this has a Thanksgivingish feel to it for western cold and snow and then again in February.

 

Scientifically, who knows though....

 

February is a nonstarter in a big El Nino year. Very likely to suck.

[richard mann]

I stopped posting simply because my life doesn't allow time for reading and posting on here anymore. Actually, I stopped reading/posting because I already know everything that is being said, and who is saying it just based on our daily weather and what the forecast models are showing... I don't choose to watch the same movie over and over again. See yall when it snows. oh and GO HAWKS! #13-3

 

Sensible, even sensical. If sadly. 

 

Although certainly begs the question, what would you like to see, rather. ?

[MossMan]

Thanksgiving weekend last year was awesome here. Not too common though. Doubt it happens two years in a row. This was 11/29/14 out here:

 

http://s28.postimg.org/uvpjf5kcd/Snow_SS.jpg

Wasn't a lot of snow, but it was still a very nice end to Nov. 2014!

[richard mann]

February is a nonstarter in a big El Nino year. Very likely to suck.

 

My view, .. Even if things "cool down" a bit main Nino focused warmth (Sea-surface, main moisture generation more strong.) more south, with the cold potential that I'm seeing more from / out of the north, the broader winter season could be a good one, right through to March.

[richard mann]

You have to post more in the winter and make us jealous.

 

Is this your first winter there?

 

Keep up Tim. 

[richard mann]

I wish it would snow in the winter. I wish people would stop hating on the Canadian.

 

There should be room for the idea (the snow one.) I'm thinking, this year.

[Phil]

Big question this winter is where the North Pacific low sets up.

This will be determined by the longitudal orientation of the low-freq tropical forcings & rate of QBO shear stress propagation. We want the forcing aggregate centered between 150W and 10E, and a slow QBO propagation in the lower sigmas.

 

If the NPAC low sets up too far northeast/over Alaska, it will flood the area with mild Pacific air and possibly couple with the PV. If it sets up south of the Aleutians, it's much easier to achieve poleward wave breaking/-EPO, which is what allowed for the Arctic event last November.

[richard mann]

.. The one better, is why (?) .. it does, where it might.

Otherwise, Phil.
 

If the NPAC low sets up too far northeast/over Alaska, it will flood the area with mild Pacific air and possibly couple with the PV. If it sets up south of the Aleutians, it's much easier to achieve poleward wave breaking/-EPO, which is what allowed for the Arctic event last November.

.. Have at it. With what then .. ?

— Being a general result, general or even shifting conditions wise. ? .. For the PNW, or even the West looked at more generally, would you say. .. ?

[ShawniganLake]

The Warm SSTA's in the NE pacific have continued to take a beating this past week.

[richard mann]

The Warm SSTA's in the NE pacific have continued to take a beating this past week. cdas-sflux_ssta7diff_global_1.png

 

Colder by the end of the first week of Oct., my best estimate.

[Jesse]

The next few days look perfect for a fall bike ride in the Puget Sound.

Don't drown!

[Jesse]

Euro sticking to its guns.

[Phil]

Beautiful Alaskan wave break on the 00z ECMWF.

 

http://catchmypicture.com/f/8CaJ9g/800.jpg

[Phil]

.. The one better, is why (?) .. it does, where it might.

 

Otherwise, Phil.

 

 

.. Have at it. With what then .. ?

 

— Being a general result, general or even shifting conditions wise. ? .. For the PNW, or even the West looked at more generally, would you say. .. ?

Convective forcing in the tropics plays a major role in where it sets up. Stronger convection in the EPAC, for example mass flux/export increase = mass imbalance at-latitude = subsequent tightening of mid latitude Ferrell cell at-longitude, hence NPAC vorticity biased east.

[TT-SEA]

00Z ECMWF still has a ULL slipping south on Friday and Saturday... but much faster and a little weaker than the 12Z run.

 

The difference is pretty significant for next weekend.

 

The 12Z run yesterday had the ULL right over Seattle on Saturday afternoon with significant rain from PDX to BLI (and probably convection) with chilly temps.    The 00Z run has the low in SW OR at that same time with sunshine for SEA and PDX and much warmer temps.   Sunday also looks sunny and warm on the 00Z run.   

 

00Z ECMWF shows the front coming through on Friday again.   I should go back and look but it seems like the vast majority of fronts have come through on Fridays since early summer.   Its really been a strange coincidence.   This past Friday was no exception with warm weather on Thursday and then much cooler with showers on Friday.

[stuffradio]

Jesse is a pluviophile.

[TT-SEA]

Was checking out where the fog was in the valleys this morning and came across this web cam from the Redmond/Sammamish area... tis the season for spiders.

 

http://s7.postimg.org/xk94m1tgb/202vc01027.jpg

[Jesse]

06z op was the warmest run yet for next weekend and beyond, but the 06z ensembles feature more members than ever with a Euro like solution. The mean is now below average for that period. Could be just a matter of time before the GFS caves.

[GHweatherChris]

Thanksgiving weekend last year was awesome here. Not too common though. Doubt it happens two years in a row. This was 11/29/14 out here:

 

http://s28.postimg.org/uvpjf5kcd/Snow_SS.jpg

It may or may not happen, it is just a gut feeling anyways.

 

But thanks for making sure to say something to downplay it as usual.

[GHweatherChris]

February is a nonstarter in a big El Nino year. Very likely to suck.

I think there is a better shot than seeing a good January.

[TT-SEA]

I think there is a better shot than seeing a good January.

Don't downplay Justin's thoughts.

[ShawniganLake]

I think there is a better shot than seeing a good January.

Nobody going with December? I think we may have a shot that month. If we are going to see a snowy holiday this winter, I would lean towards something the latter part of December.

[stuffradio]

Nobody going with December? I think we may have a shot that month. If we are going to see a snowy holiday this winter, I would lean towards something the latter part of December.

I'm going with November. It seems to be the trend these years.

[TT-SEA]

12Z GFS still showing ridging building in by Friday instead of a storm.

 

http://s11.postimg.org/andeo8v8j/gfs_namer_132_500_vort_ht.gif

 

http://s11.postimg.org/jky4llnoj/gfs_namer_156_500_vort_ht.gif

 

The ECMWF solution for next weekend is actually warmer with the ULL to our south...

http://old.ecmwf.int/products/forecasts/d/getchart/catalog/products/forecasts/medium/deterministic/msl_uv850_z500!Geopotential%20500%20hPa%20and%20Temperature%20at%20850%20hPa!168!North%20America!pop!od!oper!public_plots!2015092700!!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!192!North%20America!pop!od!oper!public_plots!2015092700!!chart.gif

[ShawniganLake]

38F here this morning. Shawnigan Lake is running a -1.3F departure for the month to this point.

[DareDuck]

You have to post more in the winter and make us jealous.

 

Is this your first winter there?

Yup. Moved here in March so we came in just at the end of winter. Can't wait for winter to come, I moved here for the cold and snow. I know we don't get a whole lot in town but most free days will be up on Bachelor.

[Jesse]

Looks like Bellingham, Olympia, Hillsboro, McMinnville and Eugene all hit 30s this morning.

 

It seems a really good leaf color season is in the making.

[TT-SEA]

12Z Canadian goes with a  ridge later in the week and next weekend. ECMWF is on its own. And even the ECMWF has warm weather next weekend.

 

http://img.meteocentre.com/models/gemglb_amer_12/GZ_D5_PN_156_0000.gif

[DareDuck]

Looks like Bellingham, Olympia, Hillsboro, McMinnville and Eugene all hit 30s this morning.

 

It seems a really good leaf color season is in the making.

32 in Bend this morning. 31 when I got to work north of town this morning.

Leaves are starting to change nicely on certain trees. The ornamental maples are really cool with the vibrant red on top, yellow in the middle, and still green at the bottom.

[Jesse]

45 at PDX this morning. Not bad at all, especially considering that tonight looks to have the potential to be a little cooler yet.

 

It took them until November 1st to reach 45 degrees or lower last year.

[Phil]

12Z Canadian goes with a ridge later in the week and next weekend. ECMWF is on its own. And even the ECMWF has warm weather next weekend.

 

 

Have to wonder if the ECMWF might be up to it's usual bias of holding back/delaying longitudinal momentum transfer underneath the trough.

 

Either way, it's going to be model mayhem as the North Pacific pattern reshuffles.

[TT-SEA]

Have to wonder if the ECMWF might be up to it's usual bias of holding back/delaying longitudinal momentum transfer underneath the trough.

Either way, it's going to be model mayhem as the North Pacific pattern reshuffles.

4 GFS ensemble members (of 12) look exactly like the 00Z ECMWF from last night. Still think ECMWF will be more right than the GFS or Canadian.

[Jesse]

Have to wonder if the ECMWF might be up to it's usual bias of holding back/delaying longitudinal momentum transfer underneath the trough.

 

Either way, it's going to be model mayhem as the North Pacific pattern reshuffles.

 

Yeah, things are clearly changing. The Alaskan vortex is going bye-bye. The models seem to be having trouble with where to move it, though. If it gets replaced with GOA ridging it could spell cool, but mostly dry weather for us.

[Jesse]

Even more ensembles jumping on board the Euro solution. Now we just need to see if the Euro keeps the Euro solution!

 

 

[Phil]

4 GFS ensemble members (of 12) look exactly like the 00Z ECMWF from last night. Still think ECMWF will be more right than the GFS or Canadian.

There are 21 members in the GEFS ensemble suite.

[Phil]

Yeah, things are clearly changing. The Alaskan vortex is going bye-bye. The models seem to be having trouble with where to move it, though. If it gets replaced with GOA ridging it could spell cool, but mostly dry weather for us.

Yeah, honestly one of the noisiest transitions I've ever seen, with several typhoons and at least three wave breaking events in conjunction over the next 10-15 days.

 

This might not be settled until 2-3 days out.