Long Range Thread 15.0

[Frank_Wx]

The long range thread is back! I locked it in the spring since very few of us pay attention to the LR in the warm climate months, and we have a dedicated tropics thread so it seemed redundant. The discussion in this thread should strictly be focused on weather patterns 7+ days from now. Often we begin to pinpoint favorable time periods for colder than normal or snowier than normal weather. It's still a little too early to talk about snow (but is it really?) but we can certainly talk about winter and a potential cold period I see in the longer range.



In the last 7 days, sea surface temperatures in the eastern Equatorial Pacific have dramatically cooled. The dark shades of blue you see there are indicative of that. While ENSO forecasts show a clear La Nina developing, we're seeing it happen real-time on SSTA (sea surface temperature anomaly) maps.



We're observing and are expected to continue observing anomalous easterly mean zonal winds (blue shading) from the Indian Ocean and points east. This 'cold' episode is indicative of La Nina conditions continuing to take shape as we head through Meteorological Fall. At present time, La Nina seems to be east-based. Over time, perhaps by winter, I can see La Nina be fairly spread out through the entire Equatorial Pacific. Easterly winds east of the Dateline are forecasted to weaken by October. However, they're expected to strengthen over or west of the Dateline.



A pretty dramatic decrease of SST's over ENSO Region 3.4 over the Summer months.





If anyone is looking for when our next taste of Fall weather arrives, the EPS and GEFS are in agreement we may see a period of below normal temperatures commencing near September 30th through the first few days of October.

Let's take a vote on who the first member will be to post a fantasy model run showing a Godzilla impacting our area. To be clear, I prefer those be posted in the Banter thread but I will not be upset if a few are posted in this thread

[billg315]

Frank, it is NEVER too early to post about snow. lol. And definitely looking forward to the return to more Fall-like temps in early October.

[billg315]

Oh, and I vote on JMan posting the first fantasy model run of a zilla

[RJB8525]

I'll go with Mugs for the first fantasy model

[amugs]

LOL RJB.!!!

I will take an East bases nine with an Easterly QBO and a positive PDO and roll with it.

[RJB8525]

LOL RJB.!!!

I will take an East bases nine with an Easterly QBO and a positive PDO and roll with it.

you're really good at posting models so i picked you first lol let it be known

[amugs]

LOL RJB.!!!

I will take an East bases nine with an Easterly QBO and a positive PDO and roll with it.

you're really good at posting models so i picked you first lol let it be known

Thanks RJB.

[amugs]

Love this chart of ENSO phases and snow totals where this is TOTALLY UNDER MEASURED in Central Park

[amugs]

Weak Nina coming in for winter and hopefully the CFSv2 is wrong cause a mod Nina will kill winter!!

[nutleyblizzard]

Weak Nina coming in for winter and hopefully the CFSv2 is wrong cause a mod Nina will kill winter!!

The only way to fend off a moderate/strong Nina is with sustained Atlantic blocking in place.Without one, the SE ridge takes over and we torch. The problem is the past several winters we've had sporadic blocking at best. Its a shame the pattern we're in now isn't happening in January. I'm with you Mugs we need this Nina to stay weak.

[sroc4]

The main reason we will be in the pattern we will be in, colder than normal in the east due to high lat blocking etc., is because of the Tropical systems in both Atlantic and Pac amplifying the polar jet.  The problem is is this will be transient.  A week, a month or a little longer we shall see but with the reason for it being in most part due to recurving trop systems.  This will not be the case heading into end Oct, Nov Dec when the trop season quiets down.

Like has been mentioned a weak to weak/mod La Nina is what we need to hope for. The stronger it is the more robust the SE ridge will be and the more difficult it will be for other more favorable conditions to counteract the negative ones.   Strat warming events for example will become that much more important in the winter months to beat back the SE ridge by compressing the tropospheric heights over NA assuming the strat warming is strong enough, and positioned in the right place of the N hemisphere.   Interesting times ahead.  I am starting to see what Tom (Isotherm) may be alluding to and that is a rogue mod to strong La Nina.  Sub surface temps cont to be robustly below normal in the Trop Pac.

[sroc4]

So we don't typically start looking at the Eurasian snow growth until October but we are currently ahead of schedule.

[amugs]

This could be a BIGGIE to winter if she blows NOW and gets her ash and particle into the stratosphere. The ring of fire is boiling now.

http://www.cnn.com/2017/09/25/asia/indonesia-bali-mount-agung/

[weatherwatchermom]

This could be a BIGGIE to winter if she blows NOW and gets her ash and particle into the stratosphere. The ring of fire is boiling now.

http://www.cnn.com/2017/09/25/asia/indonesia-bali-mount-agung/

that would create a cooling effect, correct?

[sroc4]

This could be a BIGGIE to winter if she blows NOW and gets her ash and particle into the stratosphere. The ring of fire is boiling now.

http://www.cnn.com/2017/09/25/asia/indonesia-bali-mount-agung/

that would create a cooling effect, correct?

Possibly.

[Isotherm]

I am watching Agungo closely. If it looks like we're going to see a VEI 5+ eruption, there is quite a bit of research out there regarding the atmospheric modulatory effects tropospherically, stratospherically, worldwide. What's interesting as well is that the previous major tropical volcanic eruptions occurred in El Nino events - 1963 Agungo, as moderate el nino initiated; 1982 El Chichon - as strong el nino began; and 1991 Pinatubo - as strong el nino initiated. The respective ENSO states countervailed the year 1 cooling induced by those volcanoes (delay to year 2) such that net was near zero. However, this could be a unique situation in which we see a major eruption coincident with a developing weak to moderate La Nina. Those mechanisms would act adjunctively / cumulatively as far as cooling effects induced globally, possibly yielding an even stronger cooling signal. Of course, there are a lot of IFs here, including La Nina intensity, VEI, evolution of the event, does it occur, etc.

[amugs]

I am watching Agungo closely. If it looks like we're going to see a VEI 5+ eruption,  there is quite a bit of research out there regarding the atmospheric modulatory effects tropospherically, stratospherically, worldwide. What's interesting as well is that the previous major tropical volcanic eruptions occurred in El Nino events - 1963 Agungo, as moderate el nino initiated; 1982 El Chichon - as strong el nino began; and 1991 Pinatubo - as strong el nino initiated. The respective ENSO states countervailed the year 1 cooling induced by those volcanoes (delay to year 2) such that net was near zero. However, this could be a unique situation in which we see a major eruption coincident with a developing weak to moderate La Nina. Those mechanisms would act adjunctively / cumulatively as far as cooling effects induced globally, possibly yielding an even stronger cooling signal. Of course, there are a lot of IFs here, including La Nina intensity, VEI, evolution of the event, does it occur, etc.

Awesome post and I was reading an article about as we have talked about before Tim that corelation between low.solar and seismic high activity - eq and volcanoes. It would be something to see anologies if we have any for a nina and such a massive expoison if one were to be.

[Frank_Wx]

It appears the break in temps this weekend will be temporary. The GFS and GEFS show a ridge returning to our area next week. Man, what a mild fall to this point!

[amugs]

It appears the break in temps this weekend will be temporary. The GFS and GEFS show a ridge returning to our area next week. Man, what a mild fall to this point!

Reason being - strong PAC JET extension forming - WTH with the Nina base state of the PAC we have one of these - this was the culprit last winter as well!

[sroc4]

It appears the break in temps this weekend will be temporary. The GFS and GEFS show a ridge returning to our area next week. Man, what a mild fall to this point!

Reason being - strong PAC JET extension forming  - WTH with the Nina base state of the PAC we have one of these - this was the culprit last winter as well!

Mugsy where are you getting the idea of a jet extension?  I'm not really seeing it in any of the modeling. Nothing consistent anyway.  In response to re-curving Maria we will get a transient amplification of the pattern over NA which will bring back fall like temps for late week and the weekend into the heart land and EC, but I think we simply have a base state in a La Nina type pattern setting up for the fall where we get a ridge in the east and trough in the west.  SOI has been very consistent in the La Nina territory with very transient trips towards neutral or negative.  The MJO has been pretty much a non factor in the COD.  Yet again we have the GFS showing amplification, into strong phase 8, which if correct would also promote warmer temp anomalies.  That said pretty much any time the GFS showed an MJO amplification out of the COD over the past few months it has not come to fruition.





The Euro as you can see says what amplification?  



It looks like after we move past the next week or so and the pattern relaxes some relative to the trop system influences the ensembles are hinting at the troughyness in the west and ridging in the east which is very La nina like.  But don't fret just yet as the wavelengths change as we head deeper into the colder months so the atmosphere's response to the same conditions in say Jan/Feb may be quite different meaning the trough and ridge axis would be in different positions.

[dkodgis]

And El Chichon is The Bump in English.

[amugs]

It appears the break in temps this weekend will be temporary. The GFS and GEFS show a ridge returning to our area next week. Man, what a mild fall to this point!

Reason being - strong PAC JET extension forming  - WTH with the Nina base state of the PAC we have one of these - this was the culprit last winter as well!

Scott here is the link I saw on Twitter from Ben Noll showing the PAC Jet roaaring - curse you!!!!

https://twitter.com/BenNollWeather/status/912313502865518592

[sroc4]

It appears the break in temps this weekend will be temporary. The GFS and GEFS show a ridge returning to our area next week. Man, what a mild fall to this point!

Reason being - strong PAC JET extension forming  - WTH with the Nina base state of the PAC we have one of these - this was the culprit last winter as well!

Scott here is the link I saw on Twitter from Ben Noll showing the PAC Jet roaaring - curse you!!!!

https://twitter.com/BenNollWeather/status/912313502865518592

Well the good news, if there is any good news about above normal temps, is that it may not be quite as bad as we think at least for our neck of the woods.  Ill try and explain in the other thread where you posted what at first glance appears to be a death ridge, but the positioning of the ridge isnt horrible relative to the ridging in the Atlantic.  The hot and humid days we have had over the last couple of weeks have been compliments of our tropical systems; however, the set up is shifting a little.  Yes we still have the Nina base state and ridge east/trough west, but look at the wind directions at 500mb.  Where does our air come from? More to come.

Plus if you look at the GFS and Euro modeling both show these jet extensions as transient and fluid over the N Pac.  All sorts of bends and kinks that seems to rinse wash and repeat themselves over the eastern half of the N Pac.  What that guy shows on twitter is the JMA two week avgs for weeks 1&2 and 3&4.  As we transition deeper into fall the temp gradients from N to S are starting to enhance the polar jet streams so seasonal changes combined with our La Nina base state and no other big picture drivers right now I think alot of transient rinse wash repeat type of a weather pattern is likely for some time.  Above normal temps out ahead of a front that pushes through and gives us normal to slight below normal temps briefly then back again.  As log as the ridge stays centered over the Mid west humidity hopefully wont be too bad.

[amugs]

^^^ SROC saves the day and just know I was not saying curse you to you my man just the PAC JET!!

[Isotherm]

I am watching Agungo closely. If it looks like we're going to see a VEI 5+ eruption,  there is quite a bit of research out there regarding the atmospheric modulatory effects tropospherically, stratospherically, worldwide. What's interesting as well is that the previous major tropical volcanic eruptions occurred in El Nino events - 1963 Agungo, as moderate el nino initiated; 1982 El Chichon - as strong el nino began; and 1991 Pinatubo - as strong el nino initiated. The respective ENSO states countervailed the year 1 cooling induced by those volcanoes (delay to year 2) such that net was near zero. However, this could be a unique situation in which we see a major eruption coincident with a developing weak to moderate La Nina. Those mechanisms would act adjunctively / cumulatively as far as cooling effects induced globally, possibly yielding an even stronger cooling signal. Of course, there are a lot of IFs here, including La Nina intensity, VEI, evolution of the event, does it occur, etc.

Awesome post and I was reading  an article about as we have talked about before Tim that corelation between low.solar and seismic high activity - eq and volcanoes. It would be something to see anologies if we have any for a nina and such a massive expoison if one were to be.

Thank you mugs, and agreed it would be very fascinating to watch this unfold. The meteorology/weather enthusiast community has never experienced a VEI 5+ tropical volcanic eruption with today's technology / internet, etc. Would be fun to track the impending modulation of weather on a micro and macro scale.

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