June 2016 Observation and Model Discussion for the Pacific Northwest

[VancouverIslandSouth]

Parts of Victoria are finally seeing a substantial soaking rain. Places in the east side of town have picked up as much as 19mm (0.74") in the past several hours; the west side is still mostly dry. This area seems to be on the edge of it, we've picked up some rain but the fun stuff passed just to the east.

[ShawniganLake]

Parts of Victoria are finally seeing a substantial soaking rain. Places in the east side of town have picked up as much as 19mm (0.74") in the past several hours; the west side is still mostly dry. This area seems to be on the edge of it, we've picked up some rain but the fun stuff passed just to the east.

The sun is shining here this morning.  Had a low of 41F here overnight.  The showers have been nearly stationary overnight with one very heavy cell causing flash flooding in part of west Vancouver. 

[Phil]

A warming climate contributes to this as well. And despite an inevitable step down here... its likely to continue a general upward trend overall.

The poleward migration of the Hadley Cells has probably contributed vastly more to the observed temperature trends in your region, in my opinion.

[Deweydog]

The poleward migration of the Hadley Cells has probably contributed vastly more to the observed temperature trends in your region, in my opinion.

Is "Hadley Cells" just a fancy way of saying ice?

[Front Ranger]

The -7 departure at SEA yesterday was the largest negative departure since January 2nd.

 

And the only time SEA has had a negative departure greater than -3 since January 4th.

 

The last week has really brought down the monthly departure as well which is now +4.8.

 

Down to +3.6 at OLM. Legit shot at a very close to normal month there, depending on how things break the last week of the month.

[Front Ranger]

I've barely even been on today. Most of the action has been between Tim, Phil and Flatiron. Like usual lately.

 

I was barely on yesterday.

[VancouverIslandSouth]

The sun is shining here this morning.  Had a low of 41F here overnight.  The showers have been nearly stationary overnight with one very heavy cell causing flash flooding in part of west Vancouver. 

 

The winds have shifted this morning from strong SW yesterday to weaker S/SE this morning. Perhaps the transition led to those showers becoming stationary for a period. It will be interesting to see if this change in winds will help delivery rain to previously convection shadowed locations today.

[Phil]

Is "Hadley Cells" just a fancy way of saying ice?

More of a fancy way of saying jet stream, I guess, even though they're entirely different entities.

[Phil]

Looks like La Niña is going to start throwing haymakers in July. Extratropics are showing signs of flipping into Niña/-AAM mode, inertially feeding back w/ developing Niña forcing/circulation over Pacific.

 

Anticyclonic/-PDO circulation over NPAC is already underway and looks to be a semipermanent feature going forward. Atlantic preparing to flip as well. South Pacific High is cranking. Western IO cooling relative to eastern IO.

 

Here comes the La Niña base state.

[TT-SEA]

Looks like La Niña is going to start throwing haymakers in July. Extratropics are showing signs of flipping into Niña/-AAM mode, inertially feeding back w/ developing Niña forcing/circulation over Pacific.

 

Anticyclonic/-PDO circulation over NPAC is already underway and looks to be a semipermanent feature going forward. Atlantic preparing to flip as well. South Pacific High is cranking. Western IO cooling relative to eastern IO.

 

Here comes the La Niña base state.

 

 

Given that we are a little behind from an ENSO perspective compared to some of our analog years... I assume this 'base state' was established by mid-summer in those years as well?    For example... 1966, 1973, and 1988.

[bainbridgekid]

The -7 departure at SEA yesterday was the largest negative departure since January 2nd.

 

And the only time SEA has had a negative departure greater than -3 since January 4th.

 

The last week has really brought down the monthly departure as well which is now +4.8.

That's amazing.

 

A -4 degree day is nothing special, so to go 5+ months without a single one is pretty amazing.

[Timmy Supercell]

Looks like Wunderground jumped on the GFS train. Some 80's/90's action showing up during the last half of June. 

 

I just hope storms come with that.

[TT-SEA]

Per the 12Z GFS... the slow warm up begins now and its fairly warm for the rest of the month.   Looks like a normal summer pattern is setting up now.    Maybe a little early... I still think another round of troughing and cooler/damp weather will happen in the first 7-10 days of July.

[Phil]

Given that we are a little behind from an ENSO perspective compared to some of our analog years... I assume this 'base state' was established by mid-summer in those years as well? For example... 1966, 1973, and 1988.

We're running ahead of years like 2005, 1995, 1983, 1966, and 1959. We're behind years like 2010, 1998, 1988, 1973, 1970, and 1964. Obviously the exact nature of the patterns in those years/how they evolve over North America is determined by other factors like tropical SST gradients, QBO, solar radiation fluxes, long term cell migrations, etc.

 

I'd argue we're closest overall (ENSO/AAM wise) to a blend of 2010 and 1995. However, pattern wise, without accounting for intraseasonal/timing aspects, I'd go with a blend of 1980, 1988, 1995, and 2007.

[TT-SEA]

We're running ahead of years like 2005, 1995, 1983, 1966, and 1959. We're behind years like 2010, 1998, 1988, 1973, 1970, and 1964. Obviously the exact nature of the patterns in those years/how they evolve over North America is determined by other factors like tropical SST gradients, QBO, solar radiation fluxes, long term cell migrations, etc.

 

I'd argue we're closest overall (ENSO/AAM wise) to a blend of 2010 and 1995. However, pattern wise, without accounting for intraseasonal/timing aspects, I'd go with a blend of 1980, 1988, 1995, and 2007.

 

 

I am sure there are reasons... but 1980 is still strange to me given that it was not going anywhere with ENSO that year.   That was just a warm neutral year from start to finish.   No developing moderate or strong Nina.   

 

We are playing catch up to 1988 and the Nina base state that year put us in a very consistently nice pattern for JAS.   1995 was even warmer.     2007 is interesting because the troughy period in July came a week later than I am expecting this year.     

[Phil]

Per the 12Z GFS... the slow warm up begins now and its fairly warm for the rest of the month. Looks like a normal summer pattern is setting up now. Maybe a little early... I still think another round of troughing and cooler/damp weather will happen in the first 7-10 days of July.

I don't understand this. A "normal" summer pattern would have zero geopotential height anomalies anywhere. That's a ridgy pattern, arising out of the anticyclonic breaker train response to forcing/WAF gradient over the Pacific.

[Timmy Supercell]

Per the 12Z GFS... the slow warm up begins now and its fairly warm for the rest of the month.   Looks like a normal summer pattern is setting up now.    Maybe a little early... I still think another round of troughing and cooler/damp weather will happen in the first 7-10 days of July.

 

It is more often warm/hot in the first week of July than not. Not saying it won't happen but that period is nothing like mid June where you can almost always count on the gloom.

[TT-SEA]

It is more often warm/hot in the first week of July than not. Not saying it won't happen but that period is nothing like mid June where you can almost always count on the gloom.

 

 

Not so much up here.   Troughing in the first week of July is fairly common.     

[TT-SEA]

I don't understand this. A "normal" summer pattern would have zero geopotential height anomalies anywhere. That's a ridgy pattern, arising out of the anticyclonic breaker train response to forcing/WAF gradient over the Pacific.

 

 

Weakly positive I guess.    Seems more stable without extreme heat or troughing like we have seen recently.  A more typical summer pattern.

[Timmy Supercell]

Not so much up here.   Troughing in the first week of July is fairly common.     

 

Even when I lived near Portland for years early July was always nice. And there's at least 50% chance or higher that 4th of July will be at least 80-85 or higher. The coolest of days might consist of lower 70's but still would be without clouds. I guess western WA gets more gloom than anyone else.

[TT-SEA]

Even when I lived near Portland for years early July was always nice. And there's at least 50% chance or higher that 4th of July will be at least 80-85 or higher. The coolest of days might consist of lower 70's but still would be without clouds. I guess western WA gets more gloom than anyone else.

 

 

I am sure there is a difference between SEA and PDX as well.  

[Timmy Supercell]

I am sure there is a difference between SEA and PDX as well.  

 

I guess I'm still learning about weather up there, because I've never lived north of Bethany, OR my whole life.

[Front Ranger]

That's amazing.

 

A -4 degree day is nothing special, so to go 5+ months without a single one is pretty amazing.

 

It is...but OLM has seen 10 such days since Jan 4. One of those anomaly stats where the increased UHI at SEA definitely makes a difference.

[Phil]

I am sure there are reasons... but 1980 is still strange to me given that it was not going anywhere with ENSO that year. That was just a warm neutral year from start to finish. No developing moderate or strong Nina.

 

We are playing catch up to 1988 and the Nina base state that year put us in a very consistently nice pattern for JAS. 1995 was even warmer. 2007 is interesting because the troughy period in July came a week later than I am expecting this year.

Actually, ENSO/AAM did go negative in 1980, and was falling through summer/fall. Very weak/modest, though.

 

We're way behind 1988 w/ ENSO/AAM base, but when intraseasonal forcing aligns, other factors present allow for a similar pattern over the WHEM, if that makes sense? That's the only reason I'm using it.

 

We're ahead of 1995 w/ ENSO/AAM, in the grand scheme of things, but it's a decent analog for similar reasons as 1988 is.

[Front Ranger]

Even when I lived near Portland for years early July was always nice. And there's at least 50% chance or higher that 4th of July will be at least 80-85 or higher. The coolest of days might consist of lower 70's but still would be without clouds. I guess western WA gets more gloom than anyone else.

 

Depends on where you are talking about. Areas to the north and south of Seattle are definitely cloudier/wetter than Seattle proper, due to the Olympic shadow. Seattle proper sees almost the exact same amount of sunshine yearly as Portland proper.

[TT-SEA]

Actually, ENSO/AAM did go negative in 1980, and was falling through summer/fall.

 

We're way behind 1988 w/ ENSO/AAM base, but when intraseasonal forcing aligns, other factors present allow for a similar pattern over the WHEM, if that makes sense? That's the only reason I'm using it.

 

We're ahead of 1995 w/ ENSO/AAM, in the grand scheme of things, but it's a decent analog for similar reasons as 1988 is.

 

 

The ONI and MEI were pretty much neutral for all of 1980.    And 1981 as well.

 

Really seems different to me since we are seeing such a strong flip from Nino to Nina this year.    This is much more like 1988 from that perspective.

[TT-SEA]

ONI:

 

 

Years like 1973, 1988, 1995, 1998, 2007, and 2010 stand out to me assuming that 2016 is going to put up some moderately negative numbers later this year.

[Phil]

ONI:

 

 

Years like 1973, 1988, 1995, 1998, 2007, and 2010 stand out to me assuming that 2016 is going to put up some moderately negative numbers later this year.

I think the monthly ONI would be a better guage vs the trimonthly ONI, as a reflective measure on a seasonal scale. Still, the ONI did go negative/was dropping, w/ a slight tendency for -AAM in the means.

 

http://ggweather.com/enso/oni.jpg

[TT-SEA]

I don't understand this. A "normal" summer pattern would have zero geopotential height anomalies anywhere. That's a ridgy pattern, arising out of the anticyclonic breaker train response to forcing/WAF gradient over the Pacific.

 

 

To illustrate my point... here is the 12Z GFS ensemble mean at 240 hours.

 

Very little in the way of height anomalies anywhere in the US.

 

http://mp1.met.psu.edu/~fxg1/ENSHGTAVGNH_12z/f240.gif

[Phil]

To illustrate my point... here is the 12Z GFS ensemble mean at 240 hours.

 

Very little in the way of height anomalies anywhere in the US.

 

http://mp1.met.psu.edu/~fxg1/ENSHGTAVGNH_12z/f240.gif

You were referring to the operational 12z GFS (which does not depict a "normal" summer pattern in your region, or anywhere, for that matter).

 

As for the GEFS, pointless, given its an ensemble mean. It's all over place, as usual.

[TT-SEA]

You were referring to the operational 12z GFS (which does not depict a "normal" summer pattern in your region, or anywhere, for that matter).

 

As for the GEFS, pointless, given its an ensemble mean. It's all over place, as usual.

 

 

You can see the white line representing the 12Z GFS operational run on there.   Its almost exactly like the ensemble mean.  Amazingly similar given its 10 days out.   

 

The 12Z GFS has fairly normal 500mb heights for us for the rest of the month after this trough fades away this week.  

 

The 00Z ECMWF ensemble mean is almost identical as well.     A fairly stable summer pattern without the big troughs and ridges we have seen lately.   Universal model support for this pattern right now.   Canadian is the same.   

 

http://stream.ecmwf.int/data/atls04/data/data01/scratch/ps2png-atls04-95e2cf679cd58ee9b4db4dd119a05a8d-I6cLeI.png

[TT-SEA]

Really nice day out there... much more pleasant than yesterday.   

[Phil]

You can see the white line representing the 12Z GFS operational run on there. Its almost exactly like the ensemble mean. Amazingly similar given its 10 days out.

 

The 12Z GFS has fairly normal 500mb heights for us for the rest of the month after this trough fades away this week.

 

The 00Z ECMWF ensemble mean is almost identical as well. A fairly stable summer pattern without the big troughs and ridges we have seen lately. Universal model support for this pattern right now. Canadian is the same.

 

http://stream.ecmwf.int/data/atls04/data/data01/scratch/ps2png-atls04-95e2cf679cd58ee9b4db4dd119a05a8d-I6cLeI.png

Stop playing games, I'm not in the mood.

 

Here's the 6-10 and 11-15 day 12z GFS, 500mb height anomalies. Not even close to "normal".

 

[Phil]

You need access to better maps/data.

[TT-SEA]

You need access to better maps/data.

 

 

Maybe so.

 

I just look at the 500mb pattern by day and the ensemble mean by day.

 

And it looks fairly consistent.    

 

That second map you showed looks closer to normal across the entire US.    Not that diffferent.    The pattern is of course the same since we are looking at the same models.   Just different colors.   

[TT-SEA]

The new 12Z ECMWF shows the same thing later next week... about as normal a summer set-up as possible for us.  

 

Certainly not a big ridge... nor a deep trough like we have now.

 

http://stream.ecmwf.int/data/atls15/data/data01/scratch/ps2png-atls15-95e2cf679cd58ee9b4db4dd119a05a8d-3iWE9C.png

 

http://stream.ecmwf.int/data/atls12/data/data01/scratch/ps2png-atls12-95e2cf679cd58ee9b4db4dd119a05a8d-M01ffV.png

 

http://stream.ecmwf.int/data/atls12/data/data01/scratch/ps2png-atls12-95e2cf679cd58ee9b4db4dd119a05a8d-PO5WoO.png

[Front Ranger]

Euro looks like it's setting up for another, weaker trough towards the end.

[TT-SEA]

Euro looks like it's setting up for another, weaker trough towards the end.

 

Sure does.

 

Its not heading towards any sort of big ridge out here.

[ShawniganLake]

Impressive 12pm obs from the highlands district of greater Victoria. 43F with a heavy shower overhead. Low 40s at noon in mid June is pretty D**n chilly.

[Timmy Supercell]

About 20 minutes ago I had some pea size hail falling with pretty dark skies overhead. I was probably close to getting a rumble or two but that didn't quite happen. With additional sunbreaks we should get some more convection occurring on the east sides.