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January 2020 Mid/Long Term Discussion


nj2va
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@frd there are so many variables it’s impossible to know them all. I know overall phase 7/8 in January are cold. But what does phase 8 correlate too when a purple polka dot unicorn does the Macarena while facing southeast on top of Mount Washington?  Apparently there is some obscure reason why phase 7/8/1 actually suck whenever the mjo actually goes into 7/8/1!  This would be 3 times in a row someone offered a reason why “in this very specific scenario” it’s not actually good. In 2018 things were delayed a week more than typical but an epic pattern did come in March. Yea it was March but it snowed in our area 3 times and one was significant!  They wasn’t a fluke. Last year we never got a typical phase 8 response but the wave was very weak. And when I looked into what Furtado said there was a sample size of like 3 and 1 was cold, 2 not. So how that’s statistically significant?  My guess is there are factors that can countermand the mjo or mute it. Especially when it’s a weak wave. But at some point it’s paralysis by analysis.  You break down these pattern influencers into smaller and smaller categories and you don’t have enough examples to really know anything anymore. Besides what then happens in other phases?  I asked Furtado what phases we want for cold in his specific scenario and he never answered. Was the answer we can’t get cold during low solar with a weak strat PV?  They can’t be true!  Do we want no mjo wave?  Honestly I don’t know. He didn’t answer. 

Anyhow we can’t even predict the mjo very well at long range so it’s tool in long range predictions is limited. Remember last year it looked great then suddenly collapsed through the COD and cycled right back to the warm phases. Really screwed the unanimous calls for cold.  Then after the fact a lot of people gave reasons but funny I don’t remember them saying anything before it became apparent.  

 

 

 

 

 

 

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52 minutes ago, Bob Chill said:

Extrapolating ensembles is a sure sign winter is a raging dumpster fire. 

Yea I would much rather be analyzing a 24 hour plot of moisture convergence, fgen, vorticity etc to figure out where the death band is going to set up. 

But truth is in 90% of the time I’m stuck chasing long range unicorns or day 15 pattern changes. 

Even our rare amazing winters often have lots of dead space. 3 weeks after the second Jan 1996 storm. A month between storms in 2010.  Even 2013/14 had a dead spot the second half of Dec and it was the most consistent non stop winter of my lifetime. 

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@Bob Chill @C.A.P.E.

the way the gfs goes off on that beautiful tangent actually happens at only hour 120 or so.   After the weekend storm instead of getting absorbed into the TPV that NS vort in Quebec dives in and phases with the fish storm early next week pulling it up into a 50/50. The wave break from that pumps the NAO ridge and sets to the crazy blocking across Canada that leads to everything after. That one thing sets off a chain reaction.  

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23 minutes ago, psuhoffman said:

@Bob Chill @C.A.P.E.

the way the gfs goes off on that beautiful tangent actually happens at only hour 120 or so.   After the weekend storm instead of getting absorbed into the TPV that NS vort in Quebec dives in and phases with the fish storm early next week pulling it up into a 50/50. The wave break from that pumps the NAO ridge and sets to the crazy blocking across Canada that leads to everything after. That one thing sets off a chain reaction.  

The following is not an attempt to criticize but an honest attempt to learn.  Why do you (by "you" I mean the top-tier knowledgeable weenies as opposed to random posters) analyze the operationals in the long range?  It was my understanding that they are effectively useless at that lead.  Is it just something fun to do, or is there sometimes some actually useful info buried in the trends etc?  I know that PSU has mentioned that since the GEFS is still based on the old GFS, he still looks at the GFS just so he has an idea of what the new core thinks.  Is that the only justification?

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10 minutes ago, cbmclean said:

The following is not an attempt to criticize but an honest attempt to learn.  Why do you (by "you" I mean the top-tier knowledgeable weenies as opposed to random posters) analyze the operationals in the long range?  It was my understanding that they are effectively useless at that lead.  Is it just something fun to do, or is there sometimes some actually useful info buried in the trends etc?  I know that PSU has mentioned that since the GEFS is still based on the old GFS, he still looks at the GFS just so he has an idea of what the new core thinks.  Is that the only justification?

I was mostly analyzing how the gefs was trending towards the gfs op wrt what happens in the Atlantic. 

As for the op run I was analyzing what happens around day 5 that sets off the chain reaction after. I would never waste time analyzing specifics longer out than that on an op run unless it was just to have fun. 

But the op run is a look at one permutation of the atmospheres possible outcomes.  Looking at how it got to that outcome to understand what we need to happen can be useful. Using an op run as a carbon copy forecast at day 10 or analyzing synoptic details at day 10 are a waste of time. 

 

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46 minutes ago, psuhoffman said:

GEFS is trending the right way. Look at the changes the last 3 runs wrt the 50/50 and where the ridging is centered leading into the threat.  

60330FBB-6DCB-404C-9590-3E11234B6A2C.thumb.gif.e26980d700a8aa5af8719cc4289bce2f.gif

Pumping that ridge out west... if this happens and NAO space even gets modest blocking I think we score a fun one (6+)

Is that a west-based NAO? It seems a little under the latitude for true -NAO... correct?

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23 minutes ago, psuhoffman said:

I was mostly analyzing how the gefs was trending towards the gfs op wrt what happens in the Atlantic. 

As for the op run I was analyzing what happens around day 5 that sets off the chain reaction after. I would never waste time analyzing specifics longer out than that on an op run unless it was just to have fun. 

But the op run is a look at one permutation of the atmospheres possible outcomes.  Looking at how it got to that outcome to understand what we need to happen can be useful. Using an op run as a carbon copy forecast at day 10 or analyzing synoptic details at day 10 are a waste of time. 

 

I follow your analysis and look forward to it daily, thanks

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10 minutes ago, PivotPoint said:

Pumping that ridge out west... if this happens and NAO space even gets modest blocking I think we score a fun one (6+)

Is that a west-based NAO? It seems a little under the latitude for true -NAO... correct?

It won’t show up as a -NAO because of the lower heights near Iceland. It’s not a typical NAO. But that look is good. A block across Canada with a 50/50 is a good look even if it doesn’t show as an NAO block. 

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Latest from Don S  about an hour ago. I enjoy his updates for our area  in regards to the information he presents on the MJO sand the AO. 

Here is Don's post:

<<<<

Today again saw temperatures run above normal. In the Southeast, near record and record warmth prevailed. However, the prevalent pattern that saw New York City record a mean temperature of 42.7° during January 1-15 (6th warmest on record going back to 1869) is coming to a close. Winter has not been canceled.

 

During the coming weekend, colder temperatures are likely. The temperature could even fall into the teens in New York City on Saturday morning. Afterward, even as moderation should follow for a time, the cold will likely return during the closing week of the month. At that point, the cold could become sustained and it could continue into at least the first week of February.

 

In addition, on Friday night and Saturday a system could bring New York City and Newark its first measurable snowfall since January 6. Philadelphia could receive its first measurable snowfall since December 11.

 

Initial snowfall estimates are:

 

Albany: 3"-6"

Binghamton: 3"-6"

Boston: 2"-4"

Bridgeport: 1"-3"

Islip: 2" or less

New York City: 1"-3"

Newark: 1"-3"

Philadelphia: 1"-3"

Poughkeepsie: 3"-6"

Scranton: 3"-6"

 

The ENSO Region 1+2 anomaly was +0.2°C and the Region 3.4 anomaly was +0.5°C for the week centered around January 8. For the past six weeks, the ENSO Region 1+2 anomaly has averaged +0.27°C and the ENSO Region 3.4 anomaly has averaged +0.50°C. The remainder of winter 2019-2020 will likely feature neutral-warm to weak El Niño conditions.

 

The SOI was -11.63 today.

 

Today, the preliminary Arctic Oscillation (AO) figure was +3.622.

 

The AO had a preliminary average of +3.560 during the January 1-15 period. Since 1950, there were 7 cases when the AO averaged +2.000 or above during that period. Four (57%) saw the AO average for the final 15 days of January average 1.500 or more sigma lower than the January 1-15 figure (1952, 1983, 2005, and 2007) with 1952 and 2005 having a negative average for the latter period. All four had a negative AO average for February. Three (43%) saw smaller declines (1975, 1989, and 1993). All three had February AO averages > 0.000.

 

No significant stratospheric warming event appears likely through January 23. Wave 2 activity will remain relatively suppressed. Overall, most of the stratosphere is forecast to remain cold on the EPS.

 

On January 14, the MJO was in Phase 5 at an amplitude of 3.258 (RMM). The January 13-adjusted amplitude was 3.554.

 

Since 1974, there were 8 prior cases where the MJO reached Phase 4 at an amplitude of 1.500 or above in the January 5-20 period. In 7 or 88% of those cases, the MJO progressed into Phases 7 and 8. Progression consistent with the historical experience would increase prospects for the development of a colder pattern during late January, which could continue into at least the start of February.

 

Further, the MJO was in Phase 4 at an amplitude of 2.273 on January 7 with an AO of +4.048. Since 1974, there were three January cases when the MJO was in Phase 4 at an amplitude of 2.000 or above and an AO of +3.000 or above. In all three cases the Week 3-4 period was colder than the Week 1-2 period (smallest change: 2.7° in 1993; largest change 16.8° in 2007). The change in 14-day average temperatures from the above three cases would imply a January 22-February 3 mean temperature of 10°-12° below the January 8-21 mean temperature in New York City. This data implies that the latter two week period would be colder than normal overall.

 

In addition, an MJO in Phase 7 at an amplitude of 2.000 or above typically sees measurable snowfall consistent with overall January 16-31 climatology. That would imply approximately 2 measurable snow events for Philadelphia to New York City and 2-3 such events for Boston during the closing two weeks of January. The first such event should occur this coming weekend.

 

Based on sensitivity analysis applied to the latest guidance, New York City has an implied 84% probability of a warmer than normal January. The monthly mean temperature could finish near 36.0° in New York City.

 

Finally, the latest C3S multi-system forecast suggests that the February-April temperature will likely be somewhat warmer than normal for the region (despite what could be a colder than normal February) and warmer to perhaps much warmer than normal in Europe where winter has been largely absent.

 

>>>>>

 

 

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1 hour ago, Solution Man said:

I follow your analysis and look forward to it daily, thanks

Again, I must hasten to add that was not a criticism.  I simply assume that if he mentions something on here, there is a good reason.  I just wanted to understand the reasoning behind it.

I know that he does not require kid gloves, but I do not want the rest of the forum to think I am one of those posters who comes in and gripes to show off how much they think they know.

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Just now, cbmclean said:

Again, I must hasten to add that was not a criticism.  I simply assume that if he mentions something on here, there is a good reason.  I just wanted to understand the reasoning behind it.

I know that he does not require kid gloves, but I do not want the rest of the forum to not think I am one of those posters who comes in an gripes to show off how much they think they know.

 No issues, all good my friend

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1 minute ago, jaydreb said:

No more mega block on 0z GFS and weaker 50-50 and the Day 9-10 thing is now a rainy cutter.  

It’s ok. The 50/50 is fine. The blocking is fine. But the trough cuts off over Colorado then lifts up near Chicago. That’s the issue. There is cold in front available if it took a good track. 

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