Moving on to mid/late November

[ORH_wxman]

Huh?, month 2

Well it will be the 5th month this year of a +NAO, just not consecutively...we actually had a similar stretch from late February through early May...so I was actually wrong about the blocking being gone for the first time for that length of time...although technically we did get very good blocking at the end of March and early April, but the monthlies of March and April still came out positive.

The blocking came back very strong in the summer...so perhaps it will again in the winter, but I'm a little more skeptical about it than maybe I was 90 days ago.

[Ginx snewx]

Well it will be the 5th month this year of a +NAO, just not consecutively...we actually had a similar stretch from late February through early May...so I was actually wrong about the blocking being gone for the first time for that length of time...although technically we did get very good blocking at the end of March and early April, but the monthlies of March and April still came out positive.

The blocking came back very strong in the summer...so perhaps it will again in the winter, but I'm a little more skeptical about it than maybe I was 90 days ago.

The correlation of a Neg summer and a Neg winter is very strong, a Pos Fall and a Neg winter too. Why are you more skeptical. I expect the AO to soar positive in Nov the crash again. Pretty confidant blocking has a good run coming up for our prime season.

[nzucker]

'08-'09 was kind of like that, slightly negative NAO overall...'07-'08 of course had a very +NAO but it did have its moments obviously if you were far enough north.

I'm not convinced there's going to be a lot of blocking yet. The further we go along without seeing any sign of it returning is a little concerning for those counting on it IMHO. One common theme during the past 2+ years, is that blocking seemingly wanted to always be present...when it broke down, it didn't take long for it to come back. We have essentially gone 2 months without NAO blocking now which is longest at any point in the past couple of years.

The positive zonal wind anomalies in the upper levels up in the arctic means the PV might want to be stronger than normal heading into winter.

Don't you think the lack of blocking might be related to the rapid strengthening of the Niña? Do you think as the -ENSO event matures, we might see more blocking?

I also think the Aleutian high might become stronger in winter, which leads to a chance for a -NAO as those high heights tend to bleed across the Arctic.

In Winter 10-11, the PV was generally stronger than normal, and the stratosphere colder than normal, and yet the blocking was still able to displace the cold air. I still think the SST anomalies in both the Pacific (favoring a more poleward Aleutian high) and the Atlantic (Newfoundland cold pool with warmer SSTs near Greenland) as well as the low sea ice and the decadal cycle favor a -NAO. I definitely agree that it will be more transient but overall I'm not tool worried. The vortex over Baffin Island/Canadian Archipelago could be concerning but it might just mean cold air on our side of the pole, which favors the Northern Tier if we have an Aleutian ridge and a weak block over Greenland/Iceland.

[ORH_wxman]

The correlation of a Neg summer and a Neg winter is very strong, a Pos Fall and a Neg winter too. Why are you more skeptical. I expect the AO to soar positive in Nov the crash again. Pretty confidant blocking has a good run coming up for our prime season.

I'm def aware of the correlations. I had a long thread on it back on eastern and we've talked it about over the years every autumn...but this recent run has been different for some reason. It has not been the typical oscillations that we see historically....its been just non-stop negative almost, I mean at one point we had 16 consecutive months of a -NAO and 19 out of 20...and that seems to be breaking down a bit now. Not sure what it means, but it makes me think more what is going on up there.

I'd still def lean -NAO overall, but I don't think I'd count on massive blocking up there like we saw the last 2 winters.

[Ginx snewx]

Don't you think the lack of blocking might be related to the rapid strengthening of the Niña? Do you think as the -ENSO event matures, we might see more blocking?

I also think the Aleutian high might become stronger in winter, which leads to a chance for a -NAO as those high heights tend to bleed across the Arctic.

In Winter 10-11, the PV was generally stronger than normal, and the stratosphere colder than normal, and yet the blocking was still able to displace the cold air. I still think the SST anomalies in both the Pacific (favoring a more poleward Aleutian high) and the Atlantic (Newfoundland cold pool with warmer SSTs near Greenland) as well as the low sea ice and the decadal cycle favor a -NAO. I definitely agree that it will be more transient but overall I'm not tool worried. The vortex over Baffin Island/Canadian Archipelago could be concerning but it might just mean cold air on our side of the pole, which favors the Northern Tier if we have an Aleutian ridge and a weak block over Greenland/Iceland.

At any rate the coldness of the N hemisphere should be another positive.

[OKpowdah]

I wonder if blocking will come back strong. There's no sign of it on the ensembles...esp the Atlantic side. The vortex near Baffin Island looks quite potent. The last two autumns we've seen it show up a lot...it sort of goes against the traditional relationship though as historically lots of blocking in autumn usually led to less in winter.

The upper level zonal wind anomalies have been above average for the polar vortex region.

I doubt we'll have blocking anywhere near the last two winters. However, I'm not too concerned yet about the development of a negative NAO this winter. I know the last two winters we saw strong blocking periods precede the epic winters. I bet we see model guidance coming on strong with blocking by December, but it really doesn't get going until late in the month and into January.

[ORH_wxman]

I doubt we'll have blocking anywhere near the last two winters. However, I'm not too concerned yet about the development of a negative NAO this winter. I know the last two winters we saw strong blocking periods precede the epic winters. I bet we see model guidance coming on strong with blocking by December, but it really doesn't get going until late in the month and into January.

It could def be like that. We saw this in '08-'09...we got a big block in late Dec and early Jan, then it broke down and we got another less potent block in late Jan into the first few days of Feb.

[CoastalWx]

Huh?, month 2

5th month in the last 10th. My bad, not 5 in a row.

[CoastalWx]

It could def be like that. We saw this in '08-'09...we got a big block in late Dec and early Jan, then it broke down and we got another less potent block in late Jan into the first few days of Feb.

Our guy at work seems to be liking the '08-'09 progression too..or perhaps something similar.

I don't know why Steve is taking offense..lol, but I think it is very fair to say we will not have blocking like the previous two winters. Could we have a period of strong blocking...sure, but I was thinking low end negative. Maybe -0.5 or something averaged through the period. But of course, what do I know.

Although we don't know for sure, the somewhat optic of solar could also disturb the blocking as well. I looked back at some things, and there seemed to be a relationship to the uptick in UV and/or magnetic flux. I'm still unsure of the solar aspect, but I was just trying to see if there was some sort of a correlation. I know the Ap index is low which hopefully is a plus for blocking.

[Damage In Tolland]

Are we still looking at a warm up around Helloween ensemble wise?

[Snowstorms]

Today's Euro ensembles are definitely looking chilly for early November. Not talking full blown arctic cold, but it definitely looks below average. Its been keeping heights down near and S of the Aleutians in the long range which helps pump up a bit of a PNA ridge....NAO still looks positive though.

But it has some good below average temps in central and SE Canada into our region.

We see a slight East Based -NAO developing next week which may help the storm next week tracking it just along the App. Mountains than what the 12z GFS showed. EPO remains positive however and we likely won't see any decent cold anomalies until the EPO and AO don't go negative.

'08-'09 was kind of like that, slightly negative NAO overall...'07-'08 of course had a very +NAO but it did have its moments obviously if you were far enough north.

I'm not convinced there's going to be a lot of blocking yet. The further we go along without seeing any sign of it returning is a little concerning for those counting on it IMHO. One common theme during the past 2+ years, is that blocking seemingly wanted to always be present...when it broke down, it didn't take long for it to come back. We have essentially gone 2 months without NAO blocking now which is longest at any point in the past couple of years.

The positive zonal wind anomalies in the upper levels up in the arctic means the PV might want to be stronger than normal heading into winter.

07-08 despite being a positive NAO provided a record breaking Winter for the Great Lakes region and SouthEastern Canada in general. 07-08 wasnt very cold given the +NAO/+AO anomaly but it still featured a few cold outbreaks here and there but 2008-09 was def. colder given the better NAO/AO configuration. I analyzed alot of analogues a few weeks ago and I found a interesting correlation between -NAO/-AO Winters and +NAO/+AO Autumns. I found most years that featured a +NAO/+AO anomaly in the Fall often featured the opposite in the Winter though not very extreme when comparing to the past two years but still a negative anomaly and warm stratosphere.

We need that Cold air to build up across Northern Canada for now and build the Snow/Ice cover there as a strong Cold anomaly in the Fall across Northern Canada can lead to more Arctic Outbreaks further south based on what I've seen.

Don't you think the lack of blocking might be related to the rapid strengthening of the Niña? Do you think as the -ENSO event matures, we might see more blocking?

I also think the Aleutian high might become stronger in winter, which leads to a chance for a -NAO as those high heights tend to bleed across the Arctic.

In Winter 10-11, the PV was generally stronger than normal, and the stratosphere colder than normal, and yet the blocking was still able to displace the cold air. I still think the SST anomalies in both the Pacific (favoring a more poleward Aleutian high) and the Atlantic (Newfoundland cold pool with warmer SSTs near Greenland) as well as the low sea ice and the decadal cycle favor a -NAO. I definitely agree that it will be more transient but overall I'm not tool worried. The vortex over Baffin Island/Canadian Archipelago could be concerning but it might just mean cold air on our side of the pole, which favors the Northern Tier if we have an Aleutian ridge and a weak block over Greenland/Iceland.

With a -QBO at 30hpa and slightly positive component at 50 hpa the chances of any extreme blocking are slim but the Extremely -AAO this past Winter across the SH may have been linked to the Chile Volcano Eruption and we had a similar eruption across Iceland earlier this year so lets see what happens.

Based on my research EB -NAO seems more likely than WB -NAO but I could be wrong with a decent Aleutian Ridge/-PNA/-EPO anomaly across the Pacific. SE Ridge IMO may stay consistent through the Winter though very weak when comparing to 2007-08.

Whats your thought on the AMO? The models develop a -AMO anomaly come next year. What do u think the effects wil be?

[HoarfrostHubb]

Ginxy likes the volcano angle...

Interesting post

[Ginx snewx]

Our guy at work seems to be liking the '08-'09 progression too..or perhaps something similar.

I don't know why Steve is taking offense..lol, but I think it is very fair to say we will not have blocking like the previous two winters. Could we have a period of strong blocking...sure, but I was thinking low end negative. Maybe -0.5 or something averaged through the period. But of course, what do I know.

Although we don't know for sure, the somewhat optic of solar could also disturb the blocking as well. I looked back at some things, and there seemed to be a relationship to the uptick in UV and/or magnetic flux. I'm still unsure of the solar aspect, but I was just trying to see if there was some sort of a correlation. I know the Ap index is low which hopefully is a plus for blocking.

Oh heck no, no offense at all, just read your 5 as 5 in a row. If you look at last year the blocking was more about timing rather than intensity. Dailies show the Boxing Day, Jan 12 and 19 were minimum negatives, actually the 12 19 was positive.

[ORH_wxman]

Are we still looking at a warm up around Helloween ensemble wise?

It looks a bit later on today's ensembles...a moderation around Nov 1-2 but then it gets cold again right after that. They seem fairly bullish on cold for the Nov 4-7 time frame...perhaps beyond that, but they only go out to about the 5th.

[OKpowdah]

Oh heck no, no offense at all, just read your 5 as 5 in a row. If you look at last year the blocking was more about timing rather than intensity. Dailies show the Boxing Day, Jan 12 and 19 were minimum negatives, actually the 19 was positive.

The 26th came during the pattern change from -NAO to +NAO also. It was beautifully timed

[ORH_wxman]

Oh heck no, no offense at all, just read your 5 as 5 in a row. If you look at last year the blocking was more about timing rather than intensity. Dailies show the Boxing Day, Jan 12 and 19 were minimum negatives, actually the 19 was positive.

Boxing Day came in the middle of a monster block and that block persisted until the Jan HECS. 1/12 came in a phase change and so did 1/26-27.

[Ginx snewx]

Boxing Day came in the middle of a monster block and that block persisted until the Jan HECS. 1/12 came in a phase change and so did 1/26-27.

One monster block is all it took for an epic stretch, timing.

[Ginx snewx]

Ginxy likes the volcano angle...

Interesting post

I posted several months ago the Brazilian Weather Service paper which dealt with correlations of Brazilian winters and the Northeastern US winters, an interesting piece. Going to have to check how their winter ended up.

[ORH_wxman]

One monster block is all it took for an epic stretch, timing.

Yeah...well it was a historic block, lol. One of the strongest on record. That's why I wouldn't count on it again, but who knows. We can have epic periods without historic blocks. Feb 2010 sucked for us with a ridiculous block. We often like it to ebb and flow and not be so overpowering even though we have done well in the past with those (last winter, Feb 1969, etc).

We all had a solidly above average winter in '08-'09 with an only slightly -NAO. Pike northward cleaned up in '07-'08 with a big +NAO. One of the things that makes it tough to forecast snowfall around here is we aren't as dependent on those factors as other areas. All else equal, we def like -NAOs, but it is not a death sentence if we lack huge blocking.

[ski MRG]

I posted several months ago the Brazilian Weather Service paper which dealt with correlations of Brazilian winters and the Northeastern US winters, an interesting piece. Going to have to check how their winter ended up.

That sounds interesting Ginx. Link?

[Ginx snewx]

That sounds interesting Ginx. Link?

Have to find it but yikes

In southern Peru, temperatures in the higher elevations of the Andes fell to -23°C. Since the beginning of last week 112 people have died of hypothermia and flu.

Coldest winter in 10 years

In Argentina the lowest temperatures  in 10 years were measured – the temperature dropped to -14°C. At least 33 people died, some froze to death and some from poisonous gases emitted from faulty heaters.

Thousands of cattle freeze to death in fields.

It was unusually cold in neighbouring countries. In the tropical regions of Bolivia where temperatures rarely fall below 20°C (68°F), the temperature hovered near 0°C.  At least four people died because of the cold. Two homeless persons died in Uruguay. Thousands of cattle froze in the fields in Paraguay and Brazil.

Natural gas shortages

In some areas of Bolivia and Peru, school was cancelled for some kids at the end of the week. Emergency shelters were opened for the homeless in larger cities. In Argentina some provinces faced natural gas shortages.

Heavy snow in Chile

Unusually heavy snows have fallen in parts of Chile. States of emergency have been declared in 8 communities with some buried in  up to 3 meters of snow. In the south of the country about 170 people have become isolated from supply lines.

[HoarfrostHubb]

Have to find it but yikes

So eastern Brazil was cooler than the norm, western warmer... does one have more of an affect on us as per your paper?

edit - posted this before I saw the rest of your post... interesting.

[Ginx snewx]

Geezus I almost crapped my pants when I read NOAAs winter outlook today

Northeast and Mid-Atlantic: equal chances for above-, near-, or below-normal temperatures and precipitation. Winter weather for these regions is often driven not by La Niña but by the Arctic Oscillation. If enough cold air and moisture are in place, areas north of the Ohio Valley and into the Northeast could see above-average snow;

No sh it welcome the fck aboard!! ENSO my butt!! LOL

[Ginx snewx]

Interesting brief phase change in AO at the time of next weeks modeled storm.

[Typhoon Tip]

Geezus I almost crapped my pants when I read NOAAs winter outlook today

Northeast and Mid-Atlantic: equal chances for above-, near-, or below-normal temperatures and precipitation. Winter weather for these regions is often driven not by La Niña but by the Arctic Oscillation. If enough cold air and moisture are in place, areas north of the Ohio Valley and into the Northeast could see above-average snow;

No sh it welcome the fck aboard!! ENSO my butt!! LOL

I enjoy your exuberance Ginx - really...

Yeah, I have to agree that it is nice to see NCEP stating this. I am sure their Meteorological and Climatological staff have known this for some time; but policy and bureaucrasy in any government owned operation for that matter, doesn't really lend to daily commentators having much latitude for what they are "allowed" to say. And that includes seasonal climate novelists, no doubt!

That said (and that does not impugn NCEP - not the intent anyways...), going back across the last 10 winters - if one graphs out the orientation of the temperature anomalies for N/A above the 37N's parallel, and then enters the AO/NAO (west based bias on the latter notwithstanding...) as a comparative, there is a fairly high correlation with the phase of the AO's negative versus positive phase states, particularly when time lag is applied, to the distribution of temperature departures.

Most know this intuitively in the field anyway... The problem with the bureaucrasy, though, actually stems from predictive skill, as I am interpreting things over the years. Can't say I really blame anyone; it actually seems a bit less like bureaucrasy, and more like admitting what one can and cannot do. "N/S" with regard to the NAO beyond just 5 or 6 days is a huge problem for seasonal forecasters for obvious reasons. But, the inclusion of the caveat about the Arctic Oscillation is a public acknowledgment that is hugely overdue.

***********************************************************************************************************************

I have heard it mentioned about my ideas for the first week of November. Firstly, the idea is not entirely dead, though the GFS ensemble mean is doing everything in its power to crush and shatter the vision before our very eyes. The Euro ensembles, however, are not as opposed to the idea of setting up some cold load into southern/SE Canada. I honestly don't know, particularly in mid October, which mean has the better verification numbers - but I suspect it must be the Euro. That said, the GFS was not dead to the idea, at all, as of 4 or 5 days back... The mean immediately waited until I posted that thread to start eroding the panache of that cold idea per ever cycle the mean is calculated - very funny indeed.

But, let's imagine for a second that I never started that thread. ... It is likely that Will would have mentioned in his thread that November does not look hopeless, anyway - first half included. So it is not all my fault, you can blame him for partially "Gynx"ing the idea.

Seriously though, autumn and spring are fickle with these domains. It doesn't mean one should not try to glean out pattern modalities; if there is concentrated enough evaluation one can detect subtleties about the influences et al. What once was not so subtle, became subtle at best in the GFS mean, and the Euro still nods to some degree in favor. For that, I'd suggest that the extended warm "balmitude", where it stays warm at least excuse imaginable has numbered days. How cold will it get? ...I don't know.

However, I will say that having snow around in the first week of November does not have to arrive because of a "snow storm" per se - I don't think I ever really said that honestly. All you really need is a transient cold slipping by just N of us, suppressing the baroclinic zone such that a well timed wave rides along it at this time of year - viola. In fact, the 00z CMC actually suggests that exact idea. Less reliable model, true.

[Ginx snewx]

I enjoy your exuberance Ginx - really...

Yeah, I have to agree that it is nice to see NCEP stating this. I am sure their Meteorological and Climatological staff have known this for some time; but policy and bureaucrasy in any government owned operation for that matter, doesn't really lend to daily commentators having much latitude for what they are "allowed" to say. And that includes seasonal climate novelists, no doubt!

That said (and that does not impugn NCEP - not the intent anyways...), going back across the last 10 winters - if one graphs out the orientation of the temperature anomalies for N/A above the 37N's parallel, and then enters the AO/NAO (west based bias on the latter notwithstanding...) as a comparative, there is a fairly high correlation with the phase of the AO's negative versus positive phase states, particularly when time lag is applied, to the distribution of temperature departures.

Most know this intuitively in the field anyway... The problem with the bureaucrasy, though, actually stems from predictive skill, as I am interpreting things over the years. Can't say I really blame anyone; it actually seems a bit less like bureaucrasy, and more like admitting what one can and cannot do. "N/S" with regard to the NAO beyond just 5 or 6 days is a huge problem for seasonal forecasters for obvious reasons. But, the inclusion of the caveat about the Arctic Oscillation is a public acknowledgment that is hugely overdue.

***********************************************************************************************************************

So true Tip, the constant year after year bombardment of ENSO being the main story up here, we knew what was the real deal, was aggravating.I tried to no end to change that thinking in our tiny world. It is really refreshing to see NOAA use those terms in an outlook. Great to see someone out of the box.

[HoarfrostHubb]

But does ENSO contribute even a little to our weather?

Just dropping it entirely seems hasty

[ORH_wxman]

But does ENSO contribute even a little to our weather?

Just dropping it entirely seems hasty

I think I've said probably 20 times on these boards that our winter snowfall is fairly ENSO-independent so not sure why Ginx was saying we harp on it. The reason ENSO is focused on is because its way more predictable than variable index players like the AO/NAO. You can't forecast what the NAO is going to be with any skill months in advance.

That said, we do have some ideas in ENSO relating to our weather...i.e., you often see big N/S snowfall gradients when cold ENSO is combined with -QBO. La Nina will promote a SE ridge all else being equal. EL Nino usually is warm in the upper plains and cold in the SE. So ENSO is very important when looking at the pattern as a whole...for New England specifically, we don't have a big pattern in snow for El Nino vs La Nina as I often point out when drawing up the snowfall stats...but knowing the pattern as a whole can give us an idea of what type of events might be more common (usually Ninos like coastal storms more)

[Ginx snewx]

I think I've said probably 20 times on these boards that our winter snowfall is fairly ENSO-independent so not sure why Ginx was saying we harp on it. The reason ENSO is focused on is because its way more predictable than variable index players like the AO/NAO. You can't forecast what the NAO is going to be with any skill months in advance.

That said, we do have some ideas in ENSO relating to our weather...i.e., you often see big N/S snowfall gradients when cold ENSO is combined with -QBO. La Nina will promote a SE ridge all else being equal. EL Nino usually is warm in the upper plains and cold in the SE. So ENSO is very important when looking at the pattern as a whole...for New England specifically, we don't have a big pattern in snow for El Nino vs La Nina as I often point out when drawing up the snowfall stats...but knowing the pattern as a whole can give us an idea of what type of events might be more common (usually Ninos like coastal storms more)

i was referring to the never ending national spotlght on ENSO with little or no discussion of the AO. The fact NOAA even mentioned it in a national press release is huge.

[CT Rain]

I think I've said probably 20 times on these boards that our winter snowfall is fairly ENSO-independent so not sure why Ginx was saying we harp on it. The reason ENSO is focused on is because its way more predictable than variable index players like the AO/NAO. You can't forecast what the NAO is going to be with any skill months in advance.

That said, we do have some ideas in ENSO relating to our weather...i.e., you often see big N/S snowfall gradients when cold ENSO is combined with -QBO. La Nina will promote a SE ridge all else being equal. EL Nino usually is warm in the upper plains and cold in the SE. So ENSO is very important when looking at the pattern as a whole...for New England specifically, we don't have a big pattern in snow for El Nino vs La Nina as I often point out when drawing up the snowfall stats...but knowing the pattern as a whole can give us an idea of what type of events might be more common (usually Ninos like coastal storms more)

Although a raging warm or cold ENSO phase generally isn't good in SNE. When you're talking about weak ENSO conditions there's not much of a difference.