Medium Range Discussion Winter 2011-12

[Scarlet Pimpernel]

Courtesy of the general AO+ regime and MJO, winter has started off on an unusually mild note in the East. On account, when it comes to some flowering plants, fall has apparently given way to spring in terms of their flowering. From today's edition of The Washington Post:

What began as elevated temperatures at the start of fall in parts of the United States have become “dramatically” warmer around the Great Lakes and New England, according to Deke Arndt, chief of the Climate Monitoring Branch at the National Oceanic and Atmospheric Administration’s National Climatic Data Center. And in the Washington area, the region is on track for its fourth-warmest year on record, along with its seventh-warmest December.

That, in turn, has created conditions in which plants are blooming earlier and some birds are lingering before moving south.

http://www.washingto...8vQP_story.html

For what it is worth, in Winter 2006-07, cherry blossoms burst into bloom in Boston's Public Garden in early January and bees were seen feeding on Central Park's cherry blossoms. So, such premature flowering is not unprecedented.

Interesting. You know, the other evening I was out at the Franciscan Monestary (near the Basilica in DC) to take some photos of the Christmas lights they put up and some other areas around the grounds there. Trying out a new camera I got! Anyhow, there was one place where I saw cherry trees blooming. And not just a few buds, the trees were practically in full bloom.

I've seen this before, trees or flowers being "fooled" into blooming early, etc. Saw this in Ohio a lot, mostly the crocuses would come up sometime in February or March during a warm spell, then of course it would freeze again.

I do recall winter 2006-07, and believe I recall some things blooming in January. I even remember fighting off a couple of mosquitos (aaargh, in January!). Then of course we got that amazing flip in the pattern to very cold for the next couple of months.

Hopefully, I'll be able to give the new camera a try on a decent snow before the winter is done!

[Srain]

It is encouraging to see the GFS ensembles remaining consistent for the past 5-7 days suggesting a change may well be in the works. What remains to be seen is if the pattern allows the cold air projected to build across Western Canada to spill S and affect areas in the W and Plains and leave the EC warm. With the suggestion of a weak blocking regime in the longer range, perhaps our neighbors in the E will see some semblance of a pattern change as we head deeper into January.

[usedtobe]

It is encouraging to see the GFS ensembles remaining consistent for the past 5-7 days suggesting a change may well be in the works. What remains to be seen is if the pattern allows the cold air projected to build across Western Canada to spill S and affect areas in the W and Plains and leave the EC warm. With the suggestion of a weak blocking regime in the longer range, perhaps our neighbors in the E will see some semblance of a pattern change as we head deeper into January.

I think we've seen that before during this winter. We'll need help with the pna ridge retrograding west, the east is going to struggle getting cold except maybe the northeast. For the mid atlantic the ridge needs to build and retrograde west so we can get a low locked in near 50 50 with high heights over Baffin Bay into Greenland. I don't see any hint of that on the 06Z gfs ensemble mean. Maybe the euro past day 10 looks better.

[Kevin Druff]

I don't see any hint of that on the 06Z gfs ensemble mean. Maybe the euro past day 10 looks better.

Wes, didn't your mother ever teach you that if you have nothing nice to say don't say anything at all?

[Ian]

Courtesy of the general AO+ regime and MJO, winter has started off on an unusually mild note in the East. On account, when it comes to some flowering plants, fall has apparently given way to spring in terms of their flowering. From today's edition of The Washington Post:

What began as elevated temperatures at the start of fall in parts of the United States have become “dramatically” warmer around the Great Lakes and New England, according to Deke Arndt, chief of the Climate Monitoring Branch at the National Oceanic and Atmospheric Administration’s National Climatic Data Center. And in the Washington area, the region is on track for its fourth-warmest year on record, along with its seventh-warmest December.

That, in turn, has created conditions in which plants are blooming earlier and some birds are lingering before moving south.

http://www.washingto...8vQP_story.html

For what it is worth, in Winter 2006-07, cherry blossoms burst into bloom in Boston's Public Garden in early January and bees were seen feeding on Central Park's cherry blossoms. So, such premature flowering is not unprecedented.

There's a type of cherry blossom that blooms partially in the winter. I've seen them probably every one except maybe 2009-10. This is a bit earlier than normal though, usually in Jan or Feb particularly.

[usedtobe]

Wes, didn't your mother ever teach you that if you have nothing nice to say don't say anything at all?

Well the operational GFS shows a roller coaster with a snowstorm at 360 plus hours for DC. Should get everyone excited. It also shows periods with an east based NAO but also has a pattern where the cold air should plunge into the west as the pna gives way to a rpna. Still it shows lots of amplitude so maybe that's a plus. I'd wait for the ensembles before getting to excited about the neg nao look but that's me. One thing that argues for amplitude is the mjo which is forecast to try to shift into the good phases. However, some forecasts just take it into the circle of death when it gets to 7.

[Feb]

I've decided i am jumping off the Don S express. I'm passing on the Wes Express but i'm all a board the HM Train.

[weathafella]

I think pattern change discussion often centers around ones own back yard. Northern Maine is doing ok this winter and the moose are noting this as is Vim Toot. A change in the EPO and moderation of the AO will bring many more regions into the winter is possible area. Yet some will still have a predominant torch. So to be fair, a large scale pattern change means changes un EPO/AO/NAO and there is no signal for all of these indices changing at this point.

[wolfpackmet]

Looks Like a North Central Pacific Ridge is going to open up the floodgates for the Pacific NW, Northern California in 10 days.

[usedtobe]

I've decided i am jumping off the Don S express. I'm passing on the Wes Express but i'm all a board the HM Train.

You're probably a wise man as I claim no long range skill. However, the euro 6-10 temps are going to be really ugly, it maintains low heights over Baffin Island and across Greenland and ridginess down near Spain, a classic positive nao and in the Pacific low heights over AK with high heights.

[Srain]

You're probably a wise man as I claim no long range skill. However, the euro 6-10 temps are going to be really ugly, it maintains low heights over Baffin Island and across Greenland and ridginess down near Spain, a classic positive nao and in the Pacific low heights over AK with high heights.

There is good agreement with the Euro and GFS regarding the medium range suggesting a trough from Hudson Bay into the SW as we saw during much of December. Happy New Year, Wes.

[usedtobe]

There is good agreement with the Euro and GFS regarding the medium range suggesting a trough from Hudson Bay into the SW as we saw during much of December. Happy New Year, Wes.

Happy new year to you too. I'm chilling at home the year. I do have a bottle of bubbly cooling down so I'll probably watch football in style.

[Feb]

You're probably a wise man as I claim no long range skill. However, the euro 6-10 temps are going to be really ugly, it maintains low heights over Baffin Island and across Greenland and ridginess down near Spain, a classic positive nao and in the Pacific low heights over AK with high heights.

Do you mean the very same Euro which in an early 6-10 outlook this past week had me getting 18" of snow? I'm not to concerned with one run of the euro. Besides i hear the Euro Ensembles are beginning to look a bit better in the long range.

[usedtobe]

Do you mean the very same Euro which in an early 6-10 outlook this past week had me getting 18" of snow? I'm not to concerned with one run of the euro. Besides i hear the Euro Ensembles are beginning to look a bit better in the long range.

You must have looked at different euro ensembles than I did but then I'm no long range forecaster. Here's today's d+10 euro, a positive epo and nao.

[Coach McGuirk]

Courtesy of the general AO+ regime and MJO, winter has started off on an unusually mild note in the East. On account, when it comes to some flowering plants, fall has apparently given way to spring in terms of their flowering. From today's edition of The Washington Post:

What began as elevated temperatures at the start of fall in parts of the United States have become “dramatically” warmer around the Great Lakes and New England, according to Deke Arndt, chief of the Climate Monitoring Branch at the National Oceanic and Atmospheric Administration’s National Climatic Data Center. And in the Washington area, the region is on track for its fourth-warmest year on record, along with its seventh-warmest December.

That, in turn, has created conditions in which plants are blooming earlier and some birds are lingering before moving south.

http://www.washingto...8vQP_story.html

For what it is worth, in Winter 2006-07, cherry blossoms burst into bloom in Boston's Public Garden in early January and bees were seen feeding on Central Park's cherry blossoms. So, such premature flowering is not unprecedented.

I have a rose plant blooming now.

[Kevin Druff]

Well the operational GFS shows a roller coaster with a snowstorm at 360 plus hours for DC. Should get everyone excited. It also shows periods with an east based NAO but also has a pattern where the cold air should plunge into the west as the pna gives way to a rpna. Still it shows lots of amplitude so maybe that's a plus. I'd wait for the ensembles before getting to excited about the neg nao look but that's me. One thing that argues for amplitude is the mjo which is forecast to try to shift into the good phases. However, some forecasts just take it into the circle of death when it gets to 7.

Wes, didn't your mother ever teach you that if you have nothing nice to say don't say anything at all?

Wow, that's good. I hope you didn't strain a muscle.

I'm also pretty sure that's the finest example of damning with faint praise I have ever seen.

Enjoy your bottles of bubbly!

[Srain]

The 12Z suite of operationals is in and there is some agreement regarding a robust upper low developing to our W. As we saw in December, these upper low give guidance fits and are very difficult to forecast beyond the 3-5 day range. What does appear likely is another unsettled pattern will develop next weekend with a possible Winter Storm for the Southern Rockies/S Plains and rains to the S as well as a possible coastal trough/low development as the U/L ejects NE.

[donsutherland1]

The December data is in. Some highlights:

Boston: 40.0° 9th warmest December

New York City: 43.3° 4th warmest December

Philadelphia: 43.3° 5th warmest December (back to 1825)

Washington, DC: 45.0° 7th warmest December

The result of the abnormal and persistent warmth has seen some flowering plants burst into bloom or remain in bloom. Some examples from today:

[Kevin Druff]

The December data is in. Some highlights:

Boston: 40.0° 9th warmest December

New York City: 43.3° 4th warmest December

Philadelphia: 43.3° 5th warmest December (back to 1825)

Washington, DC: 45.0° 7th warmest December

The result of the abnormal and persistent warmth has seen some flowering plants burst into bloom or remain in bloom. Some examples from today:

Yes, my broccoli has begun to form heads this week and my brussels sprouts have started to grow again. Also, my dianthus never stopped sending up blooms.

[donsutherland1]

In recent days, there has been more support on the ensembles for an AO closer to neutral down the road. A few GFS ensemble members actually tank the AO in the long range. In addition, the GFS ensembles point to the EPO heading toward neutral and then possibly negative readings. If this is right, more cold air could be available to be tapped. But where will it be focused?

The GFS ensembles also point to the PNA's continuing to decline. A negative PNA typically correlates with a trough in the West and ridge in the East. It should also be noted that the impact of the PNA is typically larger than the impact of the AO in January, though an extreme AO can overwhelm the other teleconnections.

For now, at least for me, it is too soon to speculate whether one is witnessing the seeds of a pattern change that would unfold after mid-month. That the MJO is now forecast by the GFS and ECMWF to retreat into the proverbial "circle of death" suggests a dose of caution concerning the idea of a pattern change. An alternative scenario would be a relaxation in the current pattern for a time, but not a full-fledged pattern change. I'll look for further data before reaching any conclusions on whether a pattern change is poised to develop.

What appears to be a higher confidence idea is that the probability for colder conditions in British Columbia, the Pacific Northwest, parts of the Rocky Mountains, and perhaps Plains States is growing. That should happen once the current PNA+ episode ends, possibly within the next 5-8 days. What will happen farther east remains to be seen.

At least through mid-month, it does appear that cold shots will remain largely transient, even if the upcoming one is fairly strong courtesy of the elevated PNA (now > +0.8). The upcoming one should be sufficient to produce cool anomalies in parts of the East for the current week. The January 8-15 period still looks to average milder than normal in the East.

[usedtobe]

In recent days, there has been more support on the ensembles for an AO closer to neutral down the road. A few GFS ensemble members actually tank the AO in the long range. In addition, the GFS ensembles point to the EPO heading toward neutral and then possibly negative readings. If this is right, more cold air could be available to be tapped. But where will it be focused?

The GFS ensembles also point to the PNA's continuing to decline. A negative PNA typically correlates with a trough in the West and ridge in the East. It should also be noted that the impact of the PNA is typically larger than the impact of the AO in January, though an extreme AO can overwhelm the other teleconnections.

For now, at least for me, it is too soon to speculate whether one is witnessing the seeds of a pattern change that would unfold after mid-month. That the MJO is now forecast by the GFS and ECMWF to retreat into the proverbial "circle of death" suggests a dose of caution concerning the idea of a pattern change. An alternative scenario would be a relaxation in the current pattern for a time, but not a full-fledged pattern change. I'll look for further data before reaching any conclusions on whether a pattern change is poised to develop.

What appears to be a higher confidence idea is that the probability for colder conditions in British Columbia, the Pacific Northwest, parts of the Rocky Mountains, and perhaps Plains States is growing. That should happen once the current PNA+ episode ends, possibly within the next 5-8 days. What will happen farther east remains to be seen.

At least through mid-month, it does appear that cold shots will remain largely transient, even if the upcoming one is fairly strong courtesy of the elevated PNA (now > +0.8). The upcoming one should be sufficient to produce cool anomalies in parts of the East for the current week. The January 8-15 period still looks to average milder than normal in the East.

Good post, I pretty much agree with all of it ,especially the highlighted part.

[wxmx]

Pretty much agree with Don. It looks like a pattern change, but not so much for the east. The stratosphere warming has done a number to the upper stratosphere PV, and that usually translate to a weaker troposheric PV, which is more vulnerable to planetary wave attacks. This will probably translate into a higher latitude Aleutian high, bringing down the EPO and tapping some artic air. This willl be probably far west enough so that a downstream trough develops near the W Coast, in a classic -PNA configuration. Eventually, some progress east of said ridge and if a SSW occurs, Greenland ridging could develop, bringing a fair ammount of cold for the eastern third, although this will probably happen in February. In the meantime, other than the extreme NE, I would remain cautious of any modeling cool down.

[donsutherland1]

Verification:

From 12/14/2011 (#238):

A look at composite data based on the ENSO, AO, and PNA, as well as the objective analogs argues that not all of Canada will be warmer than normal. At the same time, that data suggests the presence of a southeast ridge, which could keep the Gulf Coast warmer than normal.

Below is a chart that compares the NAEFS with the results of:

1. Composite 500 mb height anomalies based on an AO in the +1 to +2 range; PNA in the -0.75 to +0.75 range, ENSO R3.4 anomalies in the -1.50 to -0.75 range, for the 12/20-31 timeframe (1950-2010)

2. Composite 850 mb temperature anomalies based on an AO in the +1 to +2 range; PNA in the -0.75 to +0.75 range, ENSO R3.4 anomalies in the -1.50 to -0.75 range, for the 12/20-31 timeframe (1950-2010)

3. 500 mb height anomalies based on the objective analogs centered on 12/25 from the 12/14 12z run of the GFS ensembles

4. Temperature anomalies based on the objective analogs centered on 12/25 from the 12/14 12z run of the GFS ensembles

Even as the pattern is the type that could allow a cold shot into the East, with its greatest impact from the Mid-Atlantic region northward, warm anomalies will again likely outduel the cold ones. As has been the case for December to date, a large portion of the western third to half of the U.S. could wind up on the cold side of normal.

Temperature Anomalies for 12/24-31/2011:

The warmth was even more widespread than I had expected.

[The_Global_Warmer]

Verification:

From 12/14/2011 (#238):

A look at composite data based on the ENSO, AO, and PNA, as well as the objective analogs argues that not all of Canada will be warmer than normal. At the same time, that data suggests the presence of a southeast ridge, which could keep the Gulf Coast warmer than normal.

Below is a chart that compares the NAEFS with the results of:

1. Composite 500 mb height anomalies based on an AO in the +1 to +2 range; PNA in the -0.75 to +0.75 range, ENSO R3.4 anomalies in the -1.50 to -0.75 range, for the 12/20-31 timeframe (1950-2010)

2. Composite 850 mb temperature anomalies based on an AO in the +1 to +2 range; PNA in the -0.75 to +0.75 range, ENSO R3.4 anomalies in the -1.50 to -0.75 range, for the 12/20-31 timeframe (1950-2010)

3. 500 mb height anomalies based on the objective analogs centered on 12/25 from the 12/14 12z run of the GFS ensembles

4. Temperature anomalies based on the objective analogs centered on 12/25 from the 12/14 12z run of the GFS ensembles

Even as the pattern is the type that could allow a cold shot into the East, with its greatest impact from the Mid-Atlantic region northward, warm anomalies will again likely outduel the cold ones. As has been the case for December to date, a large portion of the western third to half of the U.S. could wind up on the cold side of normal.

Temperature Anomalies for 12/24-31/2011:

The warmth was even more widespread than I had expected.

Probably some enhancement going on as well from the snow albedo affect. Most of those red areas had warm patterns, but also either no snow cover and in many cases very little. The IMS Graphs/Weather Canada Graphs/Rutgers graphs over do the snow cover for some reason. Not that some is not there...but when there is 1-3cm of snow cover over hundreds of miles in Southern Canada, a lot of thatis likely bare. I remember earlier in the year some grpah showed snow where I live after we had a tenth of an inch.

We had that arctic blast come threw today. With -15 to -16C 850s(this afternoon) and a high of 34F!!!!! Hell even 2000FT hovered around -10C. We had sun so that helped, but obviously lack of snow cover played a major role.

[donsutherland1]

A quick look back at December 2011:

The AO averaged +2.221. That just missed the monthly record of +2.282, which was established in December 2006. The PNA averaged +0.36.

Overall, a comparison of the December 2011 anomalies (left) vs. the composite anomalies based on December days with an AO and PNA +/- 0.15 from the monthly averages (1950-2010):

For the most part, the December 2011 outcome and the outcome in the composite based on the AO and PNA match up very well. The most significant difference was that the highest latitudes had more warmth than what would have been suggested by the composite pattern. That additional warmth could be representative of the observed long-term warming trend that has been underway in the Arctic in recent decades.

[winterymix]

The ten day temperature departures for Alberta and other hatching grounds for our

clippers have that relatively balmy look.

[donsutherland1]

The ten day temperature departures for Alberta and other hatching grounds for our

clippers have that relatively balmy look.

For now, that appears to be the case. If some of the guidance pointing to the development of an EPO- is correct, colder air could begin returning to Canada, particularly toward mid-month. Considering that several previous EPO- forecasts have busted, I still don't place much confidence in that development. At least there's a hint of a change down the road on some of the guidance.

[Ottawa Blizzard]

Joe Bastardi is now hinting at a major flip around the middle of the month, similar to January 2007.

[donsutherland1]

Joe Bastardi is now hinting at a major flip around the middle of the month, similar to January 2007.

As noted in this thread a few days ago, there are some hints of change in the EPO, AO, and PNA. More cold air should become available. The big issue concerns whether a strong PNA- regime sets in, which would focus the cold in the west or a neutral/somewhat negative PNA regime sets up, allowing for more frequent and longer-duration cold farther east. It's still a little soon to be confident in a regime change, as models have hinted at such changes before e.g., for the second half of December, only to prove incorrect. I suspect odds are better this time around, as some of the La Niña analogs that provide insight suggest that January could be the coldest month relative to normal in the eastern half of North America this winter, even as it will likely wind up on the mild side of normal.

[BethesdaWX]

Joe Bastardi is now hinting at a major flip around the middle of the month, similar to January 2007.

As noted in this thread a few days ago, there are some hints of change in the EPO, AO, and PNA. More cold air should become available. The big issue concerns whether a strong PNA- regime sets in, which would focus the cold in the west or a neutral/somewhat negative PNA regime sets up, allowing for more frequent and longer-duration cold farther east. It's still a little soon to be confident in a regime change, as models have hinted at such changes before e.g., for the second half of December, only to prove incorrect. I suspect odds are better this time around, as some of the La Niña analogs that provide insight suggest that January could be the coldest month relative to normal in the eastern half of North America this winter, even as it will likely wind up on the mild side of normal

I'm going to bet against January turning out coldest relative to normal, in all proper analogs in the solar magnetic state (1967/68, 1978/79, 1989/90, 1999/00), All saw either a cold February and/or March. Knowing our distance from the 'true' max is 8-10 months away ((when the fields cross)) rather than the distance preceding a speedy change in more powerful cycles, this favors a brutal February in the Eastern US. I would put good money on this.

I think JB is maybe 10 days too early, based on lagged geomag activity index superimposed on current atmospheric kinetic momentum at all levels, followed by the challenge of forecasting the MJO. February should more than make up for a lackadaisical December and most of January. Call me crazy if you want.