Winter 2016-17 discussion

[LithiaWx]

Ugh,  folks the cpc maps are probabilities.  They don't forecast cold or warm. 

 

And jesus folks please don't throw out something from a reputable source because it doesn't show what you want to see.  Odds slightly favor a warmer winter to them around here.  So what?  Doesn't mean that's what's happening.  It means they see that as a more likely outcome than normal or below.  They are clearly showing that the possibilities of cold and normal are there bit with a higher chance of warmer than normal time frame.  I can also assure you they don't just use Enso as their only contributing factor.  

[packbacker]

Looking at these forcasts and seasonals that call for DJF to finish AN for the east/SE.  Only winter (-enso) that I could find where Dec was BN and DJF finished AN was 05/06.  And that winter Feb was BN too.  Here's hoping we get a BN Dec.  

Below are all the BN Dec -enso's and how Dec/Jan ended up.

 

 

[Daniel Boone]

2 hours ago, LithiaWx said:

Ugh,  folks the cpc maps are probabilities.  They don't forecast cold or warm. 

 

And jesus folks please don't throw out something from a reputable source because it doesn't show what you want to see.  Odds slightly favor a warmer winter to them around here.  So what?  Doesn't mean that's what's happening.  It means they see that as a more likely outcome than normal or below.  They are clearly showing that the possibilities of cold and normal are there bit with a higher chance of warmer than normal time frame.  I can also assure you they don't just use Enso as their only contributing factor.  

No one's bashing them per se, it's just that most of us know what a typical averaged la nina map looks like and that's it to a t.

  I've been in the wx business for about 40 years and yes they sometimes do use other variables but not often and very little. They have even said they didn't factor in blocking in their lr outlooks saying it was hard to know when it would occur. Also, in their discussions they say they don't take into account the sai in lr that it is not proven. So, what's left ? qbo, pna, wpo, epo,amo ? they don't mention whether factored or not.

   As far as reputable, just because they're a gov't agency with degreed mets doesn't mean they're good at what they do. If you kept up with their outlooks you'd see they are pretty abysmal. Many from the private sector as well as amateurs on here have outperformed them. Don't mean to bash them but, with the skills and tools they have, they could and should do better.

[PisgahNCWeather]

CPC and it's probabilities scheme. It just reminds me so much of The Naked Gun when Ed said that the doctors say that Nordberg has a 50/50 chance of living, though there's only a 10 percent chance of that.

[packbacker]

Monthly CFS starting to come around with a little better pattern for Dec.  

[Jon]

11 hours ago, Met1985 said:

Thanks Jon. Is that from today ? 

Yes, Euro Weeklies come out every Mon and Thursday around 5-6pm.

 

11 hours ago, RubiksDestroyer said:

How well have weeklies been verifying? I know the monthly (seasonal?) model runs have utterly failed, and don't have a good history over the past few winters, but I haven't seen anything about how accurate the weeklies are.

I know these pattern changes can be frustrating when they are drawn out a few weeks longer than first shown, but I'm just glad we're going through this now instead of a month later, like we did last year. I do believe that this pattern change will happen, and that the Pacific pattern will improve eventually. A big part of this will likely be the PDO; over the last couple of months, the +PDO we've seen dominate the North Pacific pattern seemed to disappear. Yet, the PDO has made an incredible comeback over the past few weeks: http://www.esrl.noaa.gov/psd/map/clim/sst.anom.anim.html. The PDO and PNA often fall into the same phase, so I anticipate that this comeback will help drive a west coast ridge as we progress into the future.

The timeline the weeklies show may work out, and if so I think it would be a very nice pattern. The movement of the trough may not be so immediate, though. I wouldn't worry if the pattern gets delayed a little bit more, as it will likely work out. Not to mention climatologically speaking, this delay (even if small) probably puts the most favorable of conditions in a more favorable time frame for snowfall.

 10-day verification score for the ECMWF EPS is 50.4% for the last 30 days, and the ECWMF Weeklies is a 46-day version of the EPS, so the idea here is to see the evolution of the overall pattern and compare that do all global models and ask yourself if it looks possible.  When you compare observations with a 46-day ensemble and say it sucks, you'll win 9/10 times. Modeling just simply isn't that powerful to predict temps across a small area of land that far out. Just open up the GFS ensemble on day 16 take a screenshot, and compare to the obs 500mb map 16 days from now and see how well it works out. Same idea here. 

10 hours ago, LithiaWx said:

Ugh,  folks the cpc maps are probabilities.  They don't forecast cold or warm. 

 

And jesus folks please don't throw out something from a reputable source because it doesn't show what you want to see.  Odds slightly favor a warmer winter to them around here.  So what?  Doesn't mean that's what's happening.  It means they see that as a more likely outcome than normal or below.  They are clearly showing that the possibilities of cold and normal are there bit with a higher chance of warmer than normal time frame.  I can also assure you they don't just use Enso as their only contributing factor.  

Yeah CPC basically copy and pasted the IRI seasonal probabilities (conspiracy). 

[LithiaWx]

16 hours ago, Daniel Boone said:

yeah, clearly nina climo composite.  they have a bad track record. looking back over the past 15 years they missed every cold winter except maybe 1; 2009-10. i think they went cold or ec then.

http://www.cpc.ncep.noaa.gov/products/predictions/long_range/tools.html

 

there are also links in there for forecast skill verification.  

http://www.cpc.ncep.noaa.gov/products/verification/summary/

[griteater]

12 hours ago, Met1985 said:

Lol no. Well we have had a positive PNA since about the middle of October to really currently but the pattern has not shown what we would think of as a positive PNA. We have had some good periods but we have also had  systems crashing into the NW. We have had record warmth in this plus Pna regime also. So how do they measure the PNA?

Here’s the +PNA pattern.  The index covers a vast domain from the Pacific Ocean, all the way across North America (PNA – Pacific North American Oscillation).  There are 4 components to a +PNA (from CPC):

 

1. Above-avg heights in the vicinity of Hawaii

2. Below-avg heights located south of the Aleutian Islands

3. Above-avg heights over the intermountain region of North America

4. Below avg heights over the southeastern U.S.

 

Each area is important in the PNA calculation…but #3 and #4 are the most important for our winter weather interests.

 

 

 

The PNA has been positive since Oct 1.  Although the Oct1-Nov16 pattern crudely matches the +PNA pattern, it doesn’t have the key couplet of W Canada above avg heights / SE U.S. below avg heights

 

[Met1985]

Thank you Griteater! 

[Jon]

I'm going to post all seasonal/climate model outputs in this thread and leave the LR thread for daily model watching. I'm getting confused. ha.

 

But the BCC model is throwing us a bone

[NWNC2015]

Brad Panovich winter outlook has above snow/ice with 1-3 big storms for anyone Charlotte to Greensboro west. Mentions cold/dry overall but with colder temps increases frozen precip risk.

[packfan98]

Here's a link to Brad P's winter forecast:

Brad P's Winter Forecast

[griteater]

Updated call for the Mid Atlantic from Roger Smith...

42 minutes ago, Roger Smith said:

My forecast --

Dec -1 anomaly, one reasonable snowfall event ... most likely timing for that is 23-25 Dec, ho ho ho.

Jan -3 anomaly, 2-3 good snowfall events ... if a memorable blizzard this winter, favored timing is 21-25 Jan.

Feb cold to start, very mild to end, one reasonable snowfall event before the transition. 

Warm March, spring early. 

 

[Jon]

Updated call for the Mid Atlantic from Roger Smith...

I agree with the warm March, weak Nina winters torch in March...strong Ninas torch in Feb, on average.

[Jon]

Just for fun, here's  the 45-day EPS snow meteogram (50 members) for RDU for the past 3 runs of the Euro Weeklies:

11/10 Weeklies: 19/50 members with snowfall through Dec 26th, 2/50 members 6"+, 0/50 10"+, mean 0.6" snow

11/14 Weeklies: 28/50 members with snowfall through Jan 1st, 4/50 members 6"+, 2/50 10"+, mean 1.5" snow

11/17 Weeklies: 31/50 members with snowfall through Jan 4th, 3/50 members 6"+, 1/50 12"+, mean 1.5" snow

 

[Poimen]

14 hours ago, griteater said:

Updated call for the Mid Atlantic from Roger Smith...

When RS barks, I listen. Hoping he's in the ballpark! 

[Met1985]

There is a lot of uncertainty in the indices. a lot of spread. I think this pattern change will collapse .  I think we see near normal temps but the cold air will be on the other side of the pole.

[Met1985]

It looks like the negative NAO will be short lived. The ao is a toss up. It could go either way really, back to positive or staying negative.

[NWNC2015]

23 minutes ago, Met1985 said:

It looks like the negative NAO will be short lived. The ao is a toss up. It could go either way really, back to positive or staying negative.

FWIW, I would be completely shocked if we do not see a winter storm before Christmas down to about 900ft in NC. We will have the cold to work with and leftover dry air near the surface from a drought with several systems to monitor as they transfer to the coast in the new pattern. I would put the odds significantly high near 30% for winter weather from now through December 10th....and near 40% by Christmas before we enter a mild period going into the New Year. 

[Lookout]

If only we could somehow tap into this.

While the North Pole warms beyond the melting point, it’s freakishly cold in Siberia

Meteorologists are having a difficult time recalling a more amazing contrast.

While the North Pole flirts with melting temperatures, Siberia is shivering in off-the-charts cold.

The Weather Channel described the stunning side-by-side extremes as “one of the most bizarre juxtapositions seen”.

The Siberian cold, up to 60 degrees below normal, has persisted for weeks. On Nov. 15, it manifested itself in more than 12 cities registering temperatures to minus-40 degrees or colder, the Weather Channel said.

 

https://www.washingtonpost.com/news/capital-weather-gang/wp/2016/11/18/while-the-north-pole-warms-beyond-the-melting-point-its-freakishly-cold-in-siberia/

[Met1985]

22 minutes ago, Lookout said:

If only we could somehow tap into this.

While the North Pole warms beyond the melting point, it’s freakishly cold in Siberia

Meteorologists are having a difficult time recalling a more amazing contrast.

While the North Pole flirts with melting temperatures, Siberia is shivering in off-the-charts cold.

The Weather Channel described the stunning side-by-side extremes as “one of the most bizarre juxtapositions seen”.

The Siberian cold, up to 60 degrees below normal, has persisted for weeks. On Nov. 15, it manifested itself in more than 12 cities registering temperatures to minus-40 degrees or colder, the Weather Channel said.

 

https://www.washingtonpost.com/news/capital-weather-gang/wp/2016/11/18/while-the-north-pole-warms-beyond-the-melting-point-its-freakishly-cold-in-siberia/

Most of the cold is on that side of the world. Even if the AO is negative it may not help us as we have already scene. It's helping Europe instead.

[mackerel_sky]

11 minutes ago, Met1985 said:

Most of the cold is on that side of the world. Even if the AO is negative it may not help us as we have already scene. It's helping Europe instead.

Winter cancel!

[Met1985]

1 minute ago, mackerel_sky said:

Winter cancel!

Lol no no. It's way to early but this has been the trend for fall. I'm not sure we have a front end winter . This year has been a year of huge uncertainty and irregular weather events . I think most forecasts are using a basis of what was normal for the past years according to ENSO and the state of everything else. I think this year will throw us several curve balls that are not the norm. I'm not being skeptical or optimistic. I'm just looking at what this crazy year has offered and I'm thinking the crazy continues . 

[packbacker]

We can work with this...-EPO/-AO/-NAO.   Need this a little deeper into Dec though.

 

 

[mrdaddyman]

On 11/18/2016 at 3:14 PM, NWNC2015 said:

Brad Panovich winter outlook has above snow/ice with 1-3 big storms for anyone Charlotte to Greensboro west. Mentions cold/dry overall but with colder temps increases frozen precip risk.

That's funny. What's new? It's almost always Charlotte to Greensboro West. I could take climo and make that forecast.

[mackerel_sky]

10 minutes ago, packbacker said:

We can work with this...-EPO/-AO/-NAO.   Need this a little deeper into Dec though.

 

 

I'd take an early December 2002 redux, and call it a winter!

[SN_Lover]

I see this winter for Charlotte verify 1 of 2 ways. 

1. Cold and below average precip with average to above average snowfall. 

2. Average temperature and zonal with below average precip and below average snowfall. 

[mackerel_sky]

1 hour ago, SN_Lover said:

I see this winter for Charlotte verify 1 of 2 ways. 

1. Cold and below average precip with average to above average snowfall. 

2. Average temperature and zonal with below average precip and below average snowfall. 

Good call! Don't forget warm with below normal snow and precip! NOAA says it can swing that way

[SN_Lover]

2 minutes ago, mackerel_sky said:

Good call! Don't forget warm with below normal snow and precip! NOAA says it can swing that way

I don't know it being warm. I side with Brad Panovitch's thoughts. I am confident that this winter will be colder than last winter at least. 

[packfan98]

Here is DT's extensive Winter Forecast.  The short version is 24 pages and the long version is 34.  Looks to have the best winter weather chances the latter half of December and January before an early spring.

DT's Winter Forecast