Medium/Long Range Discussion

[Quakertown needs snow]

^nice post Tom, thanks for the details

[NaoPos]

Man, the PAC jet is on crack right now. It's gonna be tough for any positive height anomalies over Greenland to retrograde west and give us a decent block with staying power.

Lets see how it behaves the next 2 weeks. We have a decent -AO going for us, just not gettig help from the PAC.

[famartin]

Man, the PAC jet is on crack right now. It's gonna be tough for any positive height anomalies over Greenland to retrograde west and give us a decent block with staying power.

Lets see how it behaves the next 2 weeks. We have a decent -AO going for us, just not gettig help from the PAC.

haha yeah it rained and was in the 50s here today. With winds gusting to 45-55 mph to boot.

[Quakertown needs snow]

DT video, in case anyone is interested seeing his long range views:

[NaoPos]

Current pattern:

Notice the Aleutian ridging, GOA low, neutral NAO. Hence, our 65 degree day incoming...

Now, 240hrs out on the 6z gefs:

The mega ridge over the Aleutians is gone, and the residual affect is the disappearance of the GOA vortex. However, that's retreated towards Alaska now...

Due to the neutral EPO signal and the PV in Alaska, the PAC Jet comes screaming into the west coast. Hence, you're zonal flow.

We usually end up on the torchier side of things in this type of pattern.

However, some positive height anomalies building into Greenland at this time frame. (Modeled again....) this could keep up more seasonable next week.

Finally, for giggles.. 360hrs out:

The epac ridge that we're hoping to pop a +PNA , retros back towards the Aleutian Islands.... The PV stays dominant towards western Canada and Alaska... The NAO looks decently negative, but the gefs have been showin this supposed west based -NAO 300+hrs out for a while.

While the Atlantic might cooperate, I'm not so sure of the pacific. We'll see how strong and stable that alaskan PV can become. The stronger the better....

For cAnadian snow lovers.... As we say last year, these Pv's aren't easily weakened in a higher solar cycle, lack of tropical forcing, and whatever else the meteorological world decides upon that can disrupt it. Untill we start seeing something get going to really drive this pattern. I'm not so sure us dc-NYC coastal plain peoples can cash in those aforementioned patterns.

[tombo82685]

Current pattern:

Notice the Aleutian ridging, GOA low, neutral NAO. Hence, our 65 degree day incoming...

Now, 240hrs out on the 6z gefs:

The mega ridge over the Aleutians is gone, and the residual affect is the disappearance of the GOA vortex. However, that's retreated towards Alaska now...

Due to the neutral EPO signal and the PV in Alaska, the PAC Jet comes screaming into the west coast. Hence, you're zonal flow.

We usually end up on the torchier side of things in this type of pattern.

However, some positive height anomalies building into Greenland at this time frame. (Modeled again....) this could keep up more seasonable next week.

Finally, for giggles.. 360hrs out:

The epac ridge that we're hoping to pop a +PNA , retros back towards the Aleutian Islands.... The PV stays dominant towards western Canada and Alaska... The NAO looks decently negative, but the gefs have been showin this supposed west based -NAO 300+hrs out for a while.

While the Atlantic might cooperate, I'm not so sure of the pacific. We'll see how strong and stable that alaskan PV can become. The stronger the better....

For cAnadian snow lovers.... As we say last year, these Pv's aren't easily weakened in a higher solar cycle, lack of tropical forcing, and whatever else the meteorological world decides upon that can disrupt it. Untill we start seeing something get going to really drive this pattern. I'm not so sure us dc-NYC coastal plain peoples can cash in those aforementioned patterns.

The hr 240 prog doesnt look half bad to me. Whatever that would try to cut would have to reform. Or you get wave that form on a boundry and go from like new orleans to cape may. Granted it may ne be a solid snow storm patter but that could deliver a swfe event where you get a thump then change over. The hr 360 one screams gradient.

[Porsche]

Euro weeklies are very bullish for a big -NAO...I'm surprised it keeps insisting on this. But we'll find out soon enough if its right. Basically the whole 2nd half of December it has a big -NAO right over Greenland and the Davis Straight.

Well that sounds like good news at least. One can hope.

[phlwx]

If last night's Euro is right we could be pushing 65 or warmer next Tuesday with that second storm tracking a Chicago-Saginaw track.

[am19psu]

Well that sounds like good news at least. One can hope.

Check out the banter thread from last night. I'm not ready to buy off on that solution quite yet.

[NaoPos]

If last night's Euro is right we could be pushing 65 or warmer next Tuesday with that second storm tracking a Chicago-Saginaw track.

that seams Seasonable these days....

on a more serious note, decent agreement on the 240 prog ensembles from the euro and GFS:?

untill(if?) the -NAO can build towards Greenland, we seem to be too Far East of the gradient pattern to keep any threat frozen. The longer range euro and GFS show a good example of that, as most event cut west of us.

[am19psu]

untill(if?) the -NAO can build towards Greenland, we seem to be too Far East of the gradient pattern to keep any threat frozen. The longer range euro and GFS show a good example of that, as most event cut west of us.

That about sums it up.

[Rainshadow]

That about sums it up.

SSTA seems to favor -nao east vs -nao west. Eventually the atmosphere can have its day in trumping the SSTA. But, since the NAO outlooks still are leaking statistical oil beyond day 7, I'm looking for the Pacific to rescue and right now the +epo/-pna is not much fun. It still looks like the colder air gets flopped over onto our side of the globe from Eurasia, so maybe down the road if the MJO comes out in phase 1? I'm guessing that the tropical mountain torquing not as good as latitudes farther to the north?

[am19psu]

The stratosphere seems to be the primary driver right now, Tony. Check out my posts from earlier this morning in the banter and weather question threads. MJO is in the tank through Christmas, though it looks like there might be some hope post-Xmas. I think we're going to be in the -PNA/+NAO gradient style pattern through Christmas. I think there is light at the end of the tunnel, though, unlike last winter.

[HM]

The stratosphere seems to be the primary driver right now, Tony. Check out my posts from earlier this morning in the banter and weather question threads. MJO is in the tank through Christmas, though it looks like there might be some hope post-Xmas. I think we're going to be in the -PNA/+NAO gradient style pattern through Christmas. I think there is light at the end of the tunnel, though, unlike last winter.

Check out 30mb anomalies right now:

http://www.cpc.ncep.noaa.gov/products/intraseasonal/temp30anim.shtml

Funny way to run a "close El Niño" with a -QBO over the Equator. These timely predictable warm, cool periods in the Tropics are key to convection prediction. It seems that the warming took place in mid-November when we had a relative peak in solar activity and a cooling AAO signal. Will the warming on our side / AO be enough to feedback on the Tropics?

[am19psu]

Check out 30mb anomalies right now:

http://www.cpc.ncep....emp30anim.shtml

Funny way to run a "close El Niño" with a -QBO over the Equator. These timely predictable warm, cool periods in the Tropics are key to convection prediction. It seems that the warming took place in mid-November when we had a relative peak in solar activity and a cooling AAO signal. Will the warming on our side / AO be enough to feedback on the Tropics?

Geez, no wonder the MJO totally crapped out.

You've got the equatorial-polar connection down better than I do. I usually think of the tropics always being the driver (when it exists) and I know it's not right, but I don't know the dynamics of the mid-latitudes/polar regions driving the tropics.

[HM]

Geez, no wonder the MJO totally crapped out.

You've got the equatorial-polar connection down better than I do. I usually think of the tropics always being the driver (when it exists) and I know it's not right, but I don't know the dynamics of the mid-latitudes/polar regions driving the tropics.

Well almost haha...this warming is lasting a lot longer than I thought but man it was so classic in October. The AAO went very warm, the sun crapped out and the -QBO became the dominate signal, cooling the Tropics substantially and initiating a strong convective wave. It seems like yet again a November spike in solar, aided by the AAO cooling, was enough to flip the Tropics.

The Brewer-Dobson Circulation is certainly improved from last year and Siberia is definitely doing its job but what the heck is up with the Tropics!? haha

I'm thinking it vacillates through mid-month with another surge in solar activity before cooling more substantially from stratospheric feedback and solar decline toward Christmas. Just a guess though...

[am19psu]

Well almost haha...this warming is lasting a lot longer than I thought but man it was so classic in October. The AAO went very warm, the sun crapped out and the -QBO became the dominate signal, cooling the Tropics substantially and initiating a strong convective wave. It seems like yet again a November spike in solar, aided by the AAO cooling, was enough to flip the Tropics.

The Brewer-Dobson Circulation is certainly improved from last year and Siberia is definitely doing its job but what the heck is up with the Tropics!? haha

I'm thinking it vacillates through mid-month with another surge in solar activity before cooling more substantially from stratospheric feedback and solar decline toward Christmas. Just a guess though...

That agrees with the Roundy forecasts now, too.

[tombo82685]

That agrees with the Roundy forecasts now, too.

Has roundy updated for you in the last day or so? Seems like mine is stuck on like dec 1st. This is the last image i have

[am19psu]

Has roundy updated for you in the last day or so? Seems like mine is stuck on like dec 1st. This is the last image i have

Yeah, it hasn't updated since Saturday. If it lasts through tomorrow, I was planning on sending him an email for that and to get 2013 images going.

[tombo82685]

Yeah, it hasn't updated since Saturday. If it lasts through tomorrow, I was planning on sending him an email for that and to get 2013 images going.

Lol it would be a kick in the jollie once it updates it shows that wave towards christmas fizzling like a deflated balloon...thats the only sign of hope is if that phase 8 stronger wave continue to develop.

[wederwarrior]

Well almost haha...this warming is lasting a lot longer than I thought but man it was so classic in October. The AAO went very warm, the sun crapped out and the -QBO became the dominate signal, cooling the Tropics substantially and initiating a strong convective wave. It seems like yet again a November spike in solar, aided by the AAO cooling, was enough to flip the Tropics.

The Brewer-Dobson Circulation is certainly improved from last year and Siberia is definitely doing its job but what the heck is up with the Tropics!? haha

I'm thinking it vacillates through mid-month with another surge in solar activity before cooling more substantially from stratospheric feedback and solar decline toward Christmas. Just a guess though...

Thanks for posting your thoughts.

When you say solar activity, does that mean sunspots, coronal activity, or a combination?

I was unaware of a correlation between the strotosphere and solar activity... Unless I am reading this wrong... Which is very possible.

Thanks in advance!

[Heisy]

If models hold, and we get inside 2-3 days and it looks like someone near or north of Chicago is gonna get a nice storm anyone wanna go storm chasing? PM me! If the snow ain't coming here I'll go find it!

[HM]

Thanks for posting your thoughts.

When you say solar activity, does that mean sunspots, coronal activity, or a combination?

I was unaware of a correlation between the strotosphere and solar activity... Unless I am reading this wrong... Which is very possible.

Thanks in advance!

There are a lot of linear correlations that exist between stratospheric temperatures and general solar activity, usually measured by flux data. But I've seen correlations to solar wind (CH activity) too.

Sunspot/flux activity has been correlated to equatorial and subtropical temperatures in the stratosphere and even down to the surface through more complex pathways.

[CoastalWx]

Wow, a torch at 30mb down there in the tropics. Interesting stuff guys, as always.

[tombo82685]

There are a lot of linear correlations that exist between stratospheric temperatures and general solar activity, usually measured by flux data. But I've seen correlations to solar wind (CH activity) too.

Sunspot/flux activity has been correlated to equatorial and subtropical temperatures in the stratosphere and even down to the surface through more complex pathways.

HM, what caused the splitting of the vortex to be weaker on our side compared to the other side of the globe? Also, is the increased temperatures around the equator the reason for the lack of mjo?

[HM]

HM, what caused the splitting of the vortex to be weaker on our side compared to the other side of the globe? Also, is the increased temperatures around the equator the reason for the lack of mjo?

Both of these questions don't have solid answers so I can only answer them the best I can...

The polar vortex itself is in its radiative, strengthening stage and usually builds near Baffin Island / N Pole Oct-Dec. This year it was stronger and colder than normal again. The wave 2 signal predicted by the modeling was great at long lead times but they never indicated it would be very strong. The origin of the wave was from eastern Europe / western Siberia and actually not related to the SAI or -WPO in the troposphere directly. Since the anomaly originated here and the troposphere already had the -WPO/EPO signal going, the strato-vortex was shunted to our side, weakening our wave 2 ridging signal. Now that the wave 1 configuration is coming on with a coupling between the North Pacific anticyclones between the troposphere/stratosphere now, it forced the PV to solidly congeal and position over Greenland.

It is unfortunately, just the way it went down. Had the PV been in a weakened state like 2009 or 2010 or had the wave timings been different, perhaps the NAO would have been more robust than originally predicted. The AO certainly responded but that means nothing when the NAO is more neutral. The PNA was never suppose to be blazing positive but it certainly was predicted to have occasional spikes.

I believe the lack of MJO signal can be partly to blame on the warm stratospheric temperatures above the Equator, giving stagnant forcing the lead and allowing low-pass signals to prevail. It likely isn't the only reason but that goes without saying I guess.

[tombo82685]

Both of these questions don't have solid answers so I can only answer them the best I can...

The polar vortex itself is in its radiative, strengthening stage and usually builds near Baffin Island / N Pole Oct-Dec. This year it was stronger and colder than normal again. The wave 2 signal predicted by the modeling was great at long lead times but they never indicated it would be very strong. The origin of the wave was from eastern Europe / western Siberia and actually not related to the SAI or -WPO in the troposphere directly. Since the anomaly originated here and the troposphere already had the -WPO/EPO signal going, the strato-vortex was shunted to our side, weakening our wave 2 ridging signal. Now that the wave 1 configuration is coming on with a coupling between the North Pacific anticyclones between the troposphere/stratosphere now, it forced the PV to solidly congeal and position over Greenland.

It is unfortunately, just the way it went down. Had the PV been in a weakened state like 2009 or 2010 or had the wave timings been different, perhaps the NAO would have been more robust than originally predicted. The AO certainly responded but that means nothing when the NAO is more neutral. The PNA was never suppose to be blazing positive but it certainly was predicted to have occasional spikes.

I believe the lack of MJO signal can be partly to blame on the warm stratospheric temperatures above the Equator, giving stagnant forcing the lead and allowing low-pass signals to prevail. It likely isn't the only reason but that goes without saying I guess.

i see thanks for the response...i know its way to early but do things look better towards the new year and into january?

[HM]

i see thanks for the response...i know its way to early but do things look better towards the new year and into january?

Going forward, we are going to begin influencing the tropical stratospheric temperatures during the holidays onward. We have to get beyond the next couple of weeks when declining AAM, +AAO and a slight increase in solar activity will likely prevent any serious cooling. However, the warming from Siberia will morph into a huge Aleutian High and start dislodging cooler air toward the Equator. At some point after going back and forth, I think it will cool sufficiently and reinvigorate the MJO. This could happen as soon as the end of the month, which also times nicely with the next solar decline in activity.

So January holds promise for sure along with the continued assault on the PV which may need a few extra hits to take it out. Heck, even last year's vortex took a nice beat down so this year's certainly can and most likely will.

[dssbss]

Hello,

So...I know we are in a warm period right now, but I had thought that we were supposed to turn cold or as JB says "winter starts in the east." It seems like the discussion here seems to be saying differently. I know some people on Twitter and Facebook keep posting these snow cover maps for around Christmas that look pretty impressive. I guess my question is are we expecting a pattern change mid month to a colder one or has that been pushed back indefinitely? Thanks always enjoy the discussions here (even though I don't always understand them).

[am19psu]

Short answer: I wouldn't expect anything in the way of sustained cold or decent snow chances until after Christmas (with all of the usual caveats about anything past a week or 10 days being a crap chute).