Winter 2020-2021

[40/70 Benchmark]

Lots of down time at the new job....pretty well finished with the composite framework of my winter outlook. Just gotta do the narrative and post the remained of the supplementary addendums, which explain the indexes, etc.

[RUNNAWAYICEBERG]

22 minutes ago, 40/70 Benchmark said:

Lots of down time at the new job....pretty well finished with the composite framework of my winter outlook. Just gotta do the narrative and post the remained of the supplementary addendums, which explain the indexes, etc.

Great gig when you can do your weenie work. 

[stadiumwave]

IRI Model updated

DJF

 

JFM

 

[radarman]

I think I would probably sign for that

[raindancewx]

The NAO thing I use is designed on the assumption that the changes are random, and so it should be hard to find a good match to any given set of changes. What I do find is, if the NAO has several years with similar changes, the blends work much better if the prior Nino 3.4 SST is the same. So if you just looked at 2015-16, you'd see 1968 is an amazingly close match in April to May, and March to September, in terms of how the NAO changed. But, 2015 followed an El Nino and 1968 followed a near La Nina - so the NAO match fails. This is one reason I weight ENSO order pretty highly when I analog stuff. Here is 2015:

2015   1.79   1.32   1.45   0.73   0.15  -0.07  -3.18  -0.76  -0.65   0.44   1.74   2.24

1968   0.13  -1.29   0.40  -1.08  -1.76   0.33  -0.80  -0.66  -1.92  -2.30  -0.93  -1.40

So you've got near identical March to September and April to May NAO changes. That combo doesn't exist in very many years. But the 2015-16 winter NAO was very positive, and 1968-69 was very negative. So a blend of 1992/1994, which has near identical changes to 1968 in the NAO, but nearly matches the prior Nino 3.4 reading, produces a much better outcome.

1992  -0.13   1.07   0.87   1.86   2.63   0.20   0.16   0.85  -0.44  -1.76   1.19   0.47

1994   1.04   0.46   1.26   1.14  -0.57   1.52   1.31   0.38  -1.32  -0.97   0.64   2.02

1992: -1.31 (Sept-Mar), 0.77 (May-Apr)  Nino 3.4 prior (26.76C)

1994: -2.58 (Sept-Mar), -1.71 (May-Apr) Nino 3.4 prior (27.64C)

Blend:  -1.95 (Sept-Mar), -0.47 (May-Apr) Nino 3.4 prior (27.20C)  --> DJF NAO of +1.11

2015: -2.10 (Sept-Mar), -0.58 (May-Apr) Nino 3.4 prior (27.18C) --> DJF NAO of +1.31

Basically, you have to match on the two change periods first, but it works better if you get the prior Nino 3.4 reading to match. For 1950-2019, the r-squared for March NAO to the following DJF is about 0.10 - it's not too strong. None of the months are individually, but the two changes in combination are actually pretty hard to replicate even with 70 years of data, you usually end up with less than three good matches. My rule is no match should take me more than five minutes to make by eye-balling the data. 

The data also relies on only the monthly NAO readings from 1950-2019. So pre-1995, there really isn't enough data to get good matches, since I only use years that would have been available and known to make the NAO matches. Not every year can be replicated super well with the SST prior matching. But I find it gets the NAO sign (neutral, positive, negative) right almost all years, and is +/-0.4 for the seasonal DJF value 18/25 times since 1995. The average error is about 0.36 for DJF, which is somewhat better (~40%?) than guessing the 1995-2019 NAO winter value each year.

[RUNNAWAYICEBERG]

Looks very N Stream driven. Makes sense. I’m ok with it. 

[dryslot]

Bring it all on, I'm all in for a northern stream winter, Clippers and Miller B's.

[yoda]

Well this sucks for me down here.. but perhaps you all can still cash in some?

https://www.noaa.gov/media-release/us-winter-outlook-cooler-north-warmer-south-with-ongoing-la-nina

[RUNNAWAYICEBERG]

42 minutes ago, dryslot said:

Bring it all on, I'm all in for a northern stream winter.

Yea. Those Miller B’s that spin up in gulf of Maine...I’d be ready to eat too.

[powderfreak]

2 hours ago, stadiumwave said:

IRI Model updated

DJF

 

JFM

 

That’s the look here, just a bit above normal and good precipitation.  Comfy winter recreation temps and active.  

[USCAPEWEATHERAF]

What is the latitude and longitude of the NAO/AO/PNA domains?

[CoastalWx]

Ray jeopardizing his employment on 30" of snow this winter?

[Typhoon Tip]

6 hours ago, USCAPEWEATHERAF said:

What is the latitude and longitude of the NAO/AO/PNA domains?

James .. they may vary slightly (or not...) from agency to agency but the Climate Diagnostic Center labels them as:

Pacific North America Pattern (PNA) [(15-25N, 180-140W)-(40-50N, 180-140W)+(45-60N, 125W-105W)-(25-35N, 90W-70W)]

North Atlantic Oscillation(NAO) [(35-45N, 70W-10W) - (55-70N, 70W-10W)]

Western Pacific Oscillation(WPO) [(25-40N, 140E-150W) - (50-70N, 140E-150W)]

Eastern Pacific Oscillation(EPO) [(20-35N, 160W-125W) - (55-65N, 160W-125W)]

(Couresy: https://psl.noaa.gov/forecasts/reforecast2/teleconn/ )

However, any variances between agency definitions would likely not reflect a difference in correlation significance - meaning...doesn't really matter.  

Note, due to the recent upgrades in the GEFs ensemble system, CDC's coverage/calculations necessarily need to be reconstructed; however, I shared a correspondence with personal at that office recently who indicated that there is no present funding for such an operation - therefore, public URL access to CDC - derivatives is discontinued pending further notice.  Nevertheless, these are the domain spaces that were employed for the GEFs, and though I cannot confirm this with certainty .. it is likely that any new system won't change these geographical areas - it is the data density that is the cause for the product suspension and revamp necessity.   The ECMWF and/or UKMET ( super blend..etc) may or may define their domain regions the same way. 

[40/70 Benchmark]

2 hours ago, CoastalWx said:

Ray jeopardizing his employment on 30" of snow this winter?

Nah....as long as I don't have a client scheduled, we ween.

[40/70 Benchmark]

15 hours ago, stadiumwave said:

IRI Model updated

DJF

 

JFM

 

Looks like some west-based NAO love in that forecast. 2010-11 like.

[40/70 Benchmark]

13 hours ago, raindancewx said:

The NAO thing I use is designed on the assumption that the changes are random, and so it should be hard to find a good match to any given set of changes. What I do find is, if the NAO has several years with similar changes, the blends work much better if the prior Nino 3.4 SST is the same. So if you just looked at 2015-16, you'd see 1968 is an amazingly close match in April to May, and March to September, in terms of how the NAO changed. But, 2015 followed an El Nino and 1968 followed a near La Nina - so the NAO match fails. This is one reason I weight ENSO order pretty highly when I analog stuff. Here is 2015:

2015   1.79   1.32   1.45   0.73   0.15  -0.07  -3.18  -0.76  -0.65   0.44   1.74   2.24

1968   0.13  -1.29   0.40  -1.08  -1.76   0.33  -0.80  -0.66  -1.92  -2.30  -0.93  -1.40

So you've got near identical March to September and April to May NAO changes. That combo doesn't exist in very many years. But the 2015-16 winter NAO was very positive, and 1968-69 was very negative. So a blend of 1992/1994, which has near identical changes to 1968 in the NAO, but nearly matches the prior Nino 3.4 reading, produces a much better outcome.

1992  -0.13   1.07   0.87   1.86   2.63   0.20   0.16   0.85  -0.44  -1.76   1.19   0.47

1994   1.04   0.46   1.26   1.14  -0.57   1.52   1.31   0.38  -1.32  -0.97   0.64   2.02

1992: -1.31 (Sept-Mar), 0.77 (May-Apr)  Nino 3.4 prior (26.76C)

1994: -2.58 (Sept-Mar), -1.71 (May-Apr) Nino 3.4 prior (27.64C)

Blend:  -1.95 (Sept-Mar), -0.47 (May-Apr) Nino 3.4 prior (27.20C)  --> DJF NAO of +1.11

2015: -2.10 (Sept-Mar), -0.58 (May-Apr) Nino 3.4 prior (27.18C) --> DJF NAO of +1.31

Basically, you have to match on the two change periods first, but it works better if you get the prior Nino 3.4 reading to match. For 1950-2019, the r-squared for March NAO to the following DJF is about 0.10 - it's not too strong. None of the months are individually, but the two changes in combination are actually pretty hard to replicate even with 70 years of data, you usually end up with less than three good matches. My rule is no match should take me more than five minutes to make by eye-balling the data. 

The data also relies on only the monthly NAO readings from 1950-2019. So pre-1995, there really isn't enough data to get good matches, since I only use years that would have been available and known to make the NAO matches. Not every year can be replicated super well with the SST prior matching. But I find it gets the NAO sign (neutral, positive, negative) right almost all years, and is +/-0.4 for the seasonal DJF value 18/25 times since 1995. The average error is about 0.36 for DJF, which is somewhat better (~40%?) than guessing the 1995-2019 NAO winter value each year.

I must be missing something because those bold numbers do not seem that close to me.

[Ginx snewx]

Lots of downtime in my new gig too, like all the time, so I finished my framework last month. 10-11  and might even be able to turn Feb 11 around.  La La lock it up

[Typhoon Tip]

I got a question for those individuals ...or anyone else, posting precipitation anomaly products...  

Are those 'melted' equiv.   ?

I suspect so... for science utility, snow totals really don't mean as much for climate as the precipitable water - which either snow or rain is equally rooted... which thus requires a standard mass format... Liquid is that rest state - so...  melt the snow, and call it all rain? 

I don't typically ever put much stock in those precipitation products because I noticed in the 1990s ...then more tacitly during the early 2000's...any prediction, no matter how touted the source, was 100 % always wrong       ...  hands thrown... 

It's never f'n right folks... ever - and that may be some frustration there ... fine, but the skill, at least from what I have been exposed to, just doesn't validate the effort.   I may not be completely right? - this isn't a declarative -   Just from what I've seen over the years and years and years of it ...it's on par with the Farmer's f'um Almanac if you ask me... 

Which ... I suspect their extra top secret recipe ...is really nowadays in modernity woken up to science by merely employing what everyone else does.  They have to be... unless they have some  pulsing, glowing emerald that hums and spines information lighting to some sort of mystical console that then tells them their forecast fantasy ... But then again, they'd have a bone to pick with that god because that god must be a f'n dumbasstic moron then because the FA sucks asshole too -

My advice...?  Don't  .... 

I'd suggest going with temperature alone ...and figuring that whatever falls, it'll edge heavier than the 50 or 100 year mean - relative to phenomenal circumstances - due to GW -attributed ambient increases in PWAT feeding anything that's animate in the atmosphere....  

[RUNNAWAYICEBERG]

1 hour ago, Ginx snewx said:

Lots of downtime in my new gig too, like all the time, so I finished my framework last month. 10-11  and might even be able to turn Feb 11 around.  La La lock it up

Big balls there. I haven’t seen anyone else lay there’s on the table like that so I hope yours will slap us silly. GL.

[michsnowfreak]

19 hours ago, 40/70 Benchmark said:

Lots of down time at the new job....pretty well finished with the composite framework of my winter outlook. Just gotta do the narrative and post the remained of the supplementary addendums, which explain the indexes, etc.

Glad to know I am not the only one who does my weather stuff during work lol. I usually organize my week so it's busy the 1st half and then Thursday Friday I have a lot of downtime so that's when I catch up on my weather research.

[CoastalWx]

24 minutes ago, RUNNAWAYICEBERG said:

Big balls there. I haven’t seen anyone else lay there’s on the table like that so I hope yours will slap us silly. GL.

Will he ever go for a ratter?

[stadiumwave]

2 hours ago, 40/70 Benchmark said:

Looks like some west-based NAO love in that forecast. 2010-11 like.

 

Where the warmth is located around & north of Hudson it would appear so. 

[40/70 Benchmark]

38 minutes ago, RUNNAWAYICEBERG said:

Big balls there. I haven’t seen anyone else lay there’s on the table like that so I hope yours will slap us silly. GL.

I do   when I feel it prudent to do so. 

This year, I do not. I will say that the streak of not having any month from DM average negative NAO is going to end very soon.

[40/70 Benchmark]

15 minutes ago, CoastalWx said:

Will he ever go for a ratter?

Its tough to predict something as bad as last year.

[40/70 Benchmark]

I have to be honest. I am more optimistic than I was a month ago. Only negative is the stronger than expected la nina, but given Tip's bedtime, expanding-Hadley cell erotica, that may not be such a bad thing-

SO FAR....la nina has been more deliberate with westward expansion than I had thought.

[CoastalWx]

6 minutes ago, 40/70 Benchmark said:

Its tough to predict something as bad as last year.

I mean in general. We love Steve, just busting chops. 

[CoastalWx]

1 minute ago, 40/70 Benchmark said:

I have to be honest. I am more optimistic than I was a month ago. Only negative is the stronger than expected la nina, but given Tip's bedtime, expanding-Hadley cell erotica, that may not be such a bad thing-

Just give us a half decent Atlantic. 

[40/70 Benchmark]

Just now, CoastalWx said:

Just give us a half decent Atlantic. 

I think the current structure of la nina favors that.

[RUNNAWAYICEBERG]

 

[RUNNAWAYICEBERG]

10 minutes ago, 40/70 Benchmark said:

I do   when I feel it prudent to do so. 

This year, I do not. I will say that the streak of not having any month from DM average negative NAO is going to end very soon.

I know. My point is this year I have not seen/read anyone go big.