Met Winter Banter

[40/70 Benchmark]

Well, it's quite obvious that this site is heavily snow-oriented, so while there are some warm "weenies" who might constantly disagree with snow lovers, I believe that there should be some balance in this forum. Though some more logical, reasonable debates between snow and warm lovers would definitely be appreciated what with all the constant jabs and insults being thrown back and forth between the two groups of weather lovers.

 

And even so, I'm sure that many of these "fights" between the snow and warm "weenies" are all in good humor, or at worst just some minor arguments between a couple of weather lovers who might not be getting exactly what they want in terms of weather, such as in a pattern like we're in now, and shouldn't be taken too seriously in my opinion.

Crazy idea....how about being objective, rather than offsetting one heavily biased perspective with another?

[doncat]

What happened that winter?

Anything good?

 

; 0

Nothing good at all lol...snowfall here was lowest on station record.

[CiBill]

Crazy idea....how about being objective, rather than offsetting one heavily biased perspective with another?

Crazy idea... how about paying more attention to what you read. I can tell you're looking for a fight. From what I've been reading, you've been quite angry these past few weeks towards warm weather lovers, and I'm pretty sure that's not what being objective is about.

 

What I meant in my post was for there to be more warm lovers on this site to balance the scales a bit. I didn't say for there to be more warm lovers on this site so that they can fight and argue with snow lovers.

[Isotherm]

Because this worked out so brilliantly last year. I'll believe it when I see it.

 

 

No correlation in atmospheric science will ever be 1:1; if there was, we'd have some very wealthy long range forecasters. The fact that his snow advance index failed last year is not indicative of the method's uselessness, but rather, that it is a less than perfect correlation [which we already knew]. Like all other variables, it cannot be examined in a vacuum but in concert with all other factors. The danger is becoming too reliant on one reliable and ignoring others which might be equally important. In the case of this year, there are numerous variables which support the conclusions of the SAI, namely, the reversal of the NAM.

 

This is a science, folks. If an index doesn't work in one year, it isn't "crying wolf", it's statistical reality.

[SnoSki14]

Last year has nothing to do with this year.

I think it may wait until Feb, though...the PAC will kick in for January.

That is true but how effective would a -AO be anyway this season. Everything is strongly dependent on the pacific though it can't hurt to see a -AO/NAO pop up.

I understand what you're saying Isotherm but last season that index was something everyone was harping on and it failed spectacularly. It drove home how much additional research needed to be done because its effectiveness became diluted.

It's still very useful and agree there's a lot of other variables that must be incorporated. LR forecasting is very difficult and I respect all mets who are willing to put their forecast out to the public.

[40/70 Benchmark]

That is true but how effective would a -AO be anyway this season. Everything is strongly dependent on the pacific though it can't hurt to see a -AO/NAO pop up.

The Pacific should not be hostile in Feb.

[40/70 Benchmark]

Crazy idea... how about paying more attention to what you read. I can tell you're looking for a fight. From what I've been reading, you've been quite angry these past few weeks towards warm weather lovers, and I'm pretty sure that's not what being objective is about.

 

What I meant in my post was for there to be more warm lovers on this site to balance the scales a bit. I didn't say for there to be more warm lovers on this site so that they can fight and argue with snow lovers.

I interpreted your post just fine.

My point is I think that logic is ill fated.

 

Analysis should be objective.....believe me, we break ballz all of the time in the NE thread when people are perceived to have a cold biased.

[40/70 Benchmark]

No correlation in atmospheric science will ever be 1:1; if there was, we'd have some very wealthy long range forecasters. The fact that his snow advance index failed last year is not indicative of the method's uselessness, but rather, that it is a less than perfect correlation [which we already knew]. Like all other variables, it cannot be examined in a vacuum but in concert with all other factors. The danger is becoming too reliant on one reliable and ignoring others which might be equally important. In the case of this year, there are numerous variables which support the conclusions of the SAI, namely, the reversal of the NAM.

 

This is a science, folks. If an index doesn't work in one year, it isn't "crying wolf", it's statistical reality.

Believe me, this falls on deaf/indifferent ears more often than not.

 

The correlation coefficient is roughly .7, which while far from 1, is very significant, thus it is a fact that the SAI is a valuable indicator.

If it keeps failing for the next several years, then it's usefulness will need to be reevaluated as that number drops.

[MJO812]

Because this worked out so brilliantly last year. I'll believe it when I see it.

Well he was right with the pattern change in January.

[40/70 Benchmark]

Well he was right with the pattern change in January.

He was right for the wrong reason, which is perfectly fine, I just wished he had acknowledged it.

I was in the same boat, as a lot of folks were.

Its important to acknowledge shortcomings...JMHO.

[donsutherland1]

Several points regarding the Snow Advance Index (SAI) and the Arctic Oscillation (AO):

 

The past two winters have seen the SAI fare less effectively than anticipated. Last winter's forecast was a huge miss. However, even as the consecutive failures suggests that the correlation may be weaker than had first appeared via hindcasting, that does not mean that there is no correlation. Research continues. Considering that the AO cannot be forecast reliably for more than a few weeks, even a modest improvement in prediction can yield seasonal and subseasonal forecasting improvements.

 

With regard to the current winter, the AO has averaged +1.174 so far this month. 77% of the days have seen AO+ values including 68% at +1.000 or above. However, less than 25% of meteorological winter is finished, so it's far too soon to assume that the AO will average positive for the winter or that most days will be positive. The AO needs to average -0.375 for the remainder of meteorological winter to finish with a slightly negative average. It needs to average -1.034 to finish with winter average of -0.500. Furthermore, if all remaining days were negative, the AO could still be negative on 81% of the days.

 

None of the above implies that the AO cannot flip from a predominantly positive regime to a predominantly negative one. Of the 14 cases in which December had an AO average of +1.000 or above, 50% saw either January or February (or both) have negative AO averages. The two biggest turnarounds from that sample were 1951-52 (December: +1.987; January-February: -0.654) and 1979-80 (December: +1.295; January-February: -1.519).

 

Having said this, the odds lean somewhat toward an absence of strong monthly blocking (AO average of -1.000 or below). From the above sample, 29% of cases saw either January or February have an AO average of -1.000 or below (just over 7% in January and just over 21% in February). February tended to be somewhat favored (1951-52, 2004-05, 2006-07).

 

Also, from the sample, 29% of cases saw the January-February AO average +1.000 or above and 43% saw it average +0.500 or above. 43% saw the January-February AO average < 0 and 67% of those cases were El Niño winters.

 

21% of cases saw the January-February AO average exceed the December figure (1. 1988-89: December: +1.679; January-February: +3.188); 2. 1992-93: December: +1.627; January-February: +1.924; 3. 1999-00: December: +1.043; January-February: +1.176). However, none of those cases featured El Niño winters.

 

Considering the above information, with a lot of caution for the uncertainty:

 

1. The January-February AO is very likely to average below the December figure.

2. It is very likely that either January or February will seen the AO average < 0 (the probabilities favor February).

3. It is somewhat likely that the month that averages < 0 could average -1.000 or below.

4. The AO will likely average > 0 for meteorological winter as a whole.

 

None of the above four points is cast in stone.

[MJO812]

 

Remember "The little boy who cried wolf" Newsflash: Nobody cared and his sheep died. You're sort of in that category now too

Don't post if you don't care what he has to say.

[MJO812]

He was right for the wrong reason, which is perfectly fine, I just wished he had acknowledged it.

I was in the same boat, as a lot of folks were.

Its important to acknowledge shortcomings...JMHO.

Yep. I believed he also predicted a -AO last winter but we were helped out big time because of a -EPO.

[Isotherm]

He was right for the wrong reason, which is perfectly fine, I just wished he had acknowledged it.

I was in the same boat, as a lot of folks were.

Its important to acknowledge shortcomings...JMHO.

 

 

If he had mentioned the likelihood of the EPO to be predominantly negative / PNA positive for the winter, then I would disagree. But I think he only utilized the AO. Many of us thought the EPO / PNA would be very favorable, and thus, the downstream pattern would occur largely regardless of the Arctic cooperation.

 

I agree regarding the SAI. If it fails frequently over the next several years, it may be indicative that its mostly correlation w/o causation, although I think solid science has been presented with regards to it.

[40/70 Benchmark]

If he had mentioned the likelihood of the EPO to be predominantly negative / PNA positive for the winter, then I would disagree somewhat. But I think he only utilized the AO. Many of us thought the EPO / PNA would be very favorable, and thus, the downstream pattern would occur largely regardless of the Arctic cooperation.

 

I agree regarding the SAI. If it fails frequently over the next several years, it may be indicative that its mostly correlation w/o causation, although I think solid science has been presented with regards to it.

I did, too, but still graded myself as having been right for the wrong reason.....the entire basis of that theory is the AO, which is tough to ignore.

Anyway, NBD...semantics.

[MJO812]

PNA is getting stronger each run

[Isotherm]

I did, too, but still graded myself as having been right for the wrong reason.....the entire basis of that theory is the AO, which is tough to ignore.

Anyway, NBD...semantics.

 

No doubt, I agree that it's important to acknowledge all failures. Learning can't occur if failures are ignored. Hitting all index forecasts correctly is probably more difficult than accurately forecasting the sensible weather results. Hopefully this winter will continue to shed more light on our current understanding of the AO.

[bluewave]

Only 2 out of the last 33 months had a monthly AO index of -1.000 or lower.

The previous 46 months had 13 months with a monthly AO reading of -1000 or lower.

[40/70 Benchmark]

No doubt, I agree that it's important to acknowledge all failures. Learning can't occur if failures are ignored. Hitting all index forecasts correctly is probably more difficult than accurately forecasting the sensible weather results. Hopefully this winter will continue to shed more light on our current understanding of the AO.

No doubt.

[PB GFI]

The front 15 days are probably only a few degrees above N  , the guidance suggests +3 ish , but in early Jan with the look at 500 , it is step in the right direction 

 

I have the Euro weekly 5 day panels in front of me

Jan 15- 22 , Jan  22- 29 , Jan 29 - Feb 5 

 

This could not evolve any better than what has been opined in here . According to the Euro , the pattern changes in early Jan , it is not transient and looks to lock off once past mid Jan. 

[Brian5671]

The front 15 days are probably only a few degrees above N  , the guidance suggests +3 ish , but in early Jan with the look at 500 , it is step in the right direction 

 

I have the Euro weekly 5 day panels in front of me

Jan 15- 22 , Jan  22- 29 , Jan 29 - Feb 5 

 

This could not evolve any better than what has been opined in here . According to the Euro , the pattern changes in early Jan , it is not transient and looks to lock off once past mid Jan. 

Talk dirty to me....

[wolfsheepsheadbay]

No correlation in atmospheric science will ever be 1:1; if there was, we'd have some very wealthy long range forecasters. The fact that his snow advance index failed last year is not indicative of the method's uselessness, but rather, that it is a less than perfect correlation [which we already knew]. Like all other variables, it cannot be examined in a vacuum but in concert with all other factors. The danger is becoming too reliant on one reliable and ignoring others which might be equally important. In the case of this year, there are numerous variables which support the conclusions of the SAI, namely, the reversal of the NAM.

This is a science, folks. If an index doesn't work in one year, it isn't "crying wolf", it's statistical reality.

Thanks, Tom. And thank you for continuing to post your thoughts as there is far too little LR analysis going on IMO. One can only harp on and on about record warmth for so long.

The pattern is evolving exactly as you have been suggesting and as Cohen laid out. Each ensemble run is getting better and better and in just a couple weeks we will be in MUCH better shape. The similarities to 57-58 are uncanny.

[PB GFI]

Talk dirty to me....

 

The mean ridge is slipping back to WEST of HB , the jet cuts underneath and there trough is in the SE/MA . 

It goes to the Euro seasonal . 

[wolfsheepsheadbay]

The mean ridge is slipping back to WEST of HB , the jet cuts underneath and there trough is in the SE/MA .

It goes to the Euro seasonal .

The para EPS on wxbell looks really good, eh?

[PB GFI]

The para EPS on wxbell looks really good, eh?

 

Yes . It goes to its seasonal . This is where the Euro and CFS diverge .

These 2 seasonals were in agreement in Dec . The CFS and EURO at 500 are different and will yield a different outcome .

[Brian5671]

I just hope the models aren't too quick with the pattern change-history suggests another 2-3 weeks after the initial calls for a flip.

[UnionWeatherWx]

NYC should be named "a heat island", they still don't have temps below freezing? I've done that several times already dating back to October, and I live in a pretty populated / industrialized area.

[snowman19]

Hot off the presses, the new, updated WSI forecast for January through March: http://www.wsi.com/news/scheduled-forecasts/very-warm-northern-us-winter-expected-to-continue-cooler-stormier-southern-us

[North and West of Town]

 

PNA is getting stronger each run

 

Dumb question: as a hobbyist, what does this mean?

[Brian5671]

Dumb question: as a hobbyist, what does this mean?

it's a ridge over the Rockies when it is positive which favors a trough over the Eastern US.  A -PNA is a trough over the Rockies and ridge over the east.