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January 2020 General Discussions & Observations Thread

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With regard to the Week 3 (January 10-17) Ridging in the East:

There is a wide range of thought concerning this potential ridging (the "missing piece" I alluded to yesterday on a GEFS map). Unfortunately, a day later, the EPS, GEFS, and Canadian ensembles have all "found" this piece.

That raises the question as to whether it is a realistic model depiction in a timeframe where skill scores are low.

I believe it is. This does not, of course, mean that I expect it to persist through much or all of the remainder of January. It's far too soon to make such a call. I do believe it is a crucial development that will likely lead to a warmer than normal month as a whole in much or all of the East (I'm currently thinking somewhere in the vicinity of 1.5° above normal but haven't finalized the number).

My reasoning concerning the development of the ridging is as follows:

1. The latest EPS (and GEFS) forecasts the MJO to move into Phase 5 toward January 10 (the start of the period in question).

MJO12272019.jpg

Model guidance has grown firmer on this idea in recent days, though such forecasts are still in a time range with low skill (and a wider turn that takes it through an alternative path that includes Phases 7-8-1 rather than 4-5 can't be ruled out). The fading IOD+ may also still be constructively interfering with the MJO. Rossby wave activity may also have an impact.

The 200 mb height anomaly (DJF with no lag) for Phase 5 produces a map that is quite similar to the forecast 500 mb anoamlies shown on the latest ensemble guidance (including the 6z GEFS) in the extended range:

MJO12272019-200mblaggedcomposite.jpg

Any time one of the composite maps fits modeled output suggests one should give at least some consideration to that output.

2. The 12/27 0z EPS and 12/27 6z GEFS show the development of ridging in the East in the extended range (present from hour 336 and afterward on the EPS and from hour 354 and afterward on the GEFS). The CFSv2 week 3 forecast also shows such ridging.

3. The pattern fits the January 500 mb pattern with a monthly AO of +1.000 or above and an EPO > 0 (1950-2019).

4. The ensemble forecasts call for a strong polar vortex to be present through at least January 10.

5. No significant stratospheric warming events are likely through at least the middle of the first week of January according to the EPS.

Overall, there is a body of evidence that argues for ridging to develop in the East around January 10 +/- a few days. Whether such ridging persists will depend on the progression of the MJO (will it spend appreciable time in the Maritime Continent before progressing through Phases 6 and 7 and 8 should the EPS forecast verify?) and the state of the teleconnections (persistence of AO+/EPO+).

Some of the new guidance shows the EPO falling to neutral late in the first week of January or just afterward, so that's a positive development that will need to be watched. At the same time, some of the recent guidance shows the development of a PNA- in the extended range, a development that would also favor ridging in the East.

As always, it should be noted that such forecasts have low skill and may change considerably over a week or two. Moreover, I could be wrong. The main point was that there is a body of evidence to suggest that the forecast development of ridging is plausible. The picture should become clearer over the next week.

 

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11 hours ago, donsutherland1 said:

With regard to the Week 3 (January 10-17) Ridging in the East:

There is a wide range of thought concerning this potential ridging (the "missing piece" I alluded to yesterday on a GEFS map). Unfortunately, a day later, the EPS, GEFS, and Canadian ensembles have all "found" this piece.

That raises the question as to whether it is a realistic model depiction in a timeframe where skill scores are low.

I believe it is. This does not, of course, mean that I expect it to persist through much or all of the remainder of January. It's far too soon to make such a call. I do believe it is a crucial development that will likely lead to a warmer than normal month as a whole in much or all of the East (I'm currently thinking somewhere in the vicinity of 1.5° above normal but haven't finalized the number).

My reasoning concerning the development of the ridging is as follows:

1. The latest EPS (and GEFS) forecasts the MJO to move into Phase 5 toward January 10 (the start of the period in question).

MJO12272019.jpg

Model guidance has grown firmer on this idea in recent days, though such forecasts are still in a time range with low skill (and a wider turn that takes it through an alternative path that includes Phases 7-8-1 rather than 4-5 can't be ruled out). The fading IOD+ may also still be constructively interfering with the MJO. Rossby wave activity may also have an impact.

The 200 mb height anomaly (DJF with no lag) for Phase 5 produces a map that is quite similar to the forecast 500 mb anoamlies shown on the latest ensemble guidance (including the 6z GEFS) in the extended range:

MJO12272019-200mblaggedcomposite.jpg

Any time one of the composite maps fits modeled output suggests one should give at least some consideration to that output.

2. The 12/27 0z EPS and 12/27 6z GEFS show the development of ridging in the East in the extended range (present from hour 336 and afterward on the EPS and from hour 354 and afterward on the GEFS). The CFSv2 week 3 forecast also shows such ridging.

3. The pattern fits the January 500 mb pattern with a monthly AO of +1.000 or above and an EPO > 0 (1950-2019).

4. The ensemble forecasts call for a strong polar vortex to be present through at least January 10.

5. No significant stratospheric warming events are likely through at least the middle of the first week of January according to the EPS.

Overall, there is a body of evidence that argues for ridging to develop in the East around January 10 +/- a few days. Whether such ridging persists will depend on the progression of the MJO (will it spend appreciable time in the Maritime Continent before progressing through Phases 6 and 7 and 8 should the EPS forecast verify?) and the state of the teleconnections (persistence of AO+/EPO+).

Some of the new guidance shows the EPO falling to neutral late in the first week of January or just afterward, so that's a positive development that will need to be watched. At the same time, some of the recent guidance shows the development of a PNA- in the extended range, a development that would also favor ridging in the East.

As always, it should be noted that such forecasts have low skill and may change considerably over a week or two. Moreover, I could be wrong. The main point was that there is a body of evidence to suggest that the forecast development of ridging is plausible. The picture should become clearer over the next week.

 

Great write-up Don. It's interesting that, up here in Canada, Environment Canada was the only outlet which called for a mild winter. It was against the grain, and raised eyebrows in other weather outlets; The Weather Network called for a much colder than average winter across much of Ontario. It's looking increasingly likely that Environment Canada and the NWS were right, while Canada's Weather Network and Weatherbell Analytics were wrong.

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18 minutes ago, Ottawa Blizzard said:

Great write-up Don. It's interesting that, up here in Canada, Environment Canada was the only outlet which called for a mild winter. It was against the grain, and raised eyebrows in other weather outlets; The Weather Network called for a much colder than average winter across much of Ontario. It's looking increasingly likely that Environment Canada and the NWS were right, while Canada's Weather Network and Weatherbell Analytics were wrong.

Thanks Ottawa Blizzard. I hope all is well with you.

I'm not sure what The Weather Network and Weatherbell saw or on which they based their forecasts. The composite temperature anomalies for neutral-warm/borderline weak El Nino cases didn't favor widespread cold in Canada (northern Canada was favored), especially in Ontario. The C3S multi-system guidance also favored warmth across a large part of Canada. Toronto will likely wind up having a warmer than normal winter. Unfortunately, snowfall appears to be in line for a below normal season.

 

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9 hours ago, donsutherland1 said:

Thanks Ottawa Blizzard. I hope all is well with you.

I'm not sure what The Weather Network and Weatherbell saw or on which they based their forecasts. The composite temperature anomalies for neutral-warm/borderline weak El Nino cases didn't favor widespread cold in Canada (northern Canada was favored), especially in Ontario. The C3S multi-system guidance also favored warmth across a large part of Canada. Toronto will likely wind up having a warmer than normal winter. Unfortunately, snowfall appears to be in line for a below normal season.

 

I'm not sure about The Weather Network Don, but Weatherbell seems to have been basing their forecast on the warm water south of Alaska, and how this apparently led to cold in years like 2003, 2014, and 2015. However, it has to be said that, on his blog this morning, Joe Bastardi has drawn attention to the winter of 1936-1937, which apparently also had warm water in the Gulf of Alaska, but ended up with a warm winter in eastern North America, following a colder than average November. Here is a link to that winter's observations in Toronto.

https://climate.weather.gc.ca/climate_data/daily_data_e.html?hlyRange=1953-01-01|1969-05-31&dlyRange=1840-03-01|2017-04-27&mlyRange=1840-01-01|2006-12-01&StationID=5051&Prov=ON&urlExtension=_e.html&searchType=stnName&optLimit=yearRange&StartYear=1840&EndYear=1977&selRowPerPage=25&Line=0&searchMethod=contains&txtStationName=Toronto&timeframe=2&Day=1&Year=1937&Month=1

 

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10 hours ago, donsutherland1 said:

Thanks Ottawa Blizzard. I hope all is well with you.

I'm not sure what The Weather Network and Weatherbell saw or on which they based their forecasts. The composite temperature anomalies for neutral-warm/borderline weak El Nino cases didn't favor widespread cold in Canada (northern Canada was favored), especially in Ontario. The C3S multi-system guidance also favored warmth across a large part of Canada. Toronto will likely wind up having a warmer than normal winter. Unfortunately, snowfall appears to be in line for a below normal season.

 

Hi Don, with regard to The Weather Network's forecast, please see the link below.

 

https://www.theweathernetwork.com/ca/news/article/canadas-winter-forecast-update-2019-2020-winter-pattern-locks-in-for-january

 

I think it goes without saying that their forecast is in trouble.

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The beginning of January doesn't look good. Hopefully we can get into a better pattern from mid January through mid March, maybe even through March, with a few shots at snow. I think if we get that, and throw in a big Miller A the whole forum would be happy. We need to keep reminding ourselves that winter just started.

Sent from my Lenovo TB-X605F using Tapatalk

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There's a wee bit of uncertainty regarding the MJO next week.

Some keep it in the COD, some are low amplitude in phases 4-5, and some are very high amplitude in those same phases.

Whichever one ends up being right could determine how warm/cold January gets. Both low & high amplitude 4/5 phases will lead to an AN Jan but it'll mean the difference between +1/1.5 or +3 to +5 or better.

Right now a transient cold (maybe arctic?) shot still appears likely after Jan 5. 

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1 hour ago, Snow88 said:

Way too many people giving up on  January.  

Noting that there will be a mild start should not be seen as giving up. Big flips have occurred in the past i.e., 2005 and 2007. Hopefully, we will see something similar this time around. 

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31 minutes ago, donsutherland1 said:

Noting that there will be a mild start should not be seen as giving up. Big flips have occurred in the past i.e., 2005 and 2007. Hopefully, we will see something similar this time around. 

The 1st full week of January looks to be cold enough for snow with plenty of potential for snow on the 12Z GFS

gfs_T850_us_43.png

 

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37 minutes ago, NEG NAO said:

The 1st full week of January looks to be cold enough for snow with plenty of potential for snow on the 12Z GFS

gfs_T850_us_43.png

 

The cmc brings the vortex into central illinios and the 0c 850s into central florida. Suppressive look there

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28 minutes ago, binbisso said:

The cmc brings the vortex into central illinios and the 0c 850s into central florida. Suppressive look there

gem_T850_us_41.png
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12 minutes ago, Snow88 said:

Euro is similar 

(seems like I am the only one around here who knows how to cut and paste images)

850tw.conus.png

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Quick follow up on the discussion concerning possible East Coast ridging for the January 10-17 period:

1. The 12z EPS builds the ridging, especially from 300 hours to 360 hours

2. The 12z GEFS shows some ridging now, but it could be transient there. Still that's a pretty big change from 24-48 hours ago.

3. The ECMWF still shows the MJO briefing passing through Phases 7-8 and then entering the dreaded Maritime Continent at high and increasing amplitude in the extended range. 

So, at least for now, my concerns about the specified period above persist, namely that transient cold could give way to a period of milder conditions. Afterward, much will depend on the MJO's progression and the evolution of the teleconnections.

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LaMarcus Thompson's   "Switchback Railway" had better curves than this back in 1884.

Even some of the web's worst X_Rated pages have better curves too.............eke!

2019122812_054@007_E1_knyc_I_NAEFS@EPSGR

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8 hours ago, SnoSki14 said:

There's a wee bit of uncertainty regarding the MJO next week.

Some keep it in the COD, some are low amplitude in phases 4-5, and some are very high amplitude in those same phases.

Whichever one ends up being right could determine how warm/cold January gets. Both low & high amplitude 4/5 phases will lead to an AN Jan but it'll mean the difference between +1/1.5 or +3 to +5 or better.

Right now a transient cold (maybe arctic?) shot still appears likely after Jan 5. 

It looks like pretty good agreement between the Euro, GFS, and CMC on the MJO. Lingering mild phase 5-6 influence to start out January. Then a shift to colder a few days later after we go through phase 7-8. Followed by a shift back to mild with phase 4-5. So The January 1-15 progression should be mild...cold...mild. Exact dates of the quick transitions to be determined later. The GFS VP anomalies eventually get out of the the COD and over to 4-5 like the other models. The GFS can struggle with those RMM charts. That why I like to look at the VP anomalies. 
 

 

 

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9 hours ago, Ottawa Blizzard said:

Hi Don, with regard to The Weather Network's forecast, please see the link below.

 

https://www.theweathernetwork.com/ca/news/article/canadas-winter-forecast-update-2019-2020-winter-pattern-locks-in-for-january

 

I think it goes without saying that their forecast is in trouble.

The forecast map suggests a warmer than usual Alaska, which was indeed the case until recently. However, there appears to have been a shift towards much colder since about the start of winter on Dec 22, with much below normal temperatures. So perhaps there will be some revision in the near future..

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9 minutes ago, bluewave said:

It looks like pretty good agreement between the Euro, GFS, and CMC on the MJO. Lingering mild phase 5-6 influence to start out January. Then a shift to colder a few days later after we go through phase 7-8. Followed by a shift back to mild with phase 4-5. So The January 1-15 progression should be mild...cold...mild. Exact dates of the quick transitions to be determined later. The GFS VP anomalies eventually get out of the the COD and over to 4-5 like the other models. The GFS can struggle with those RMM charts. That why I like to look at the VP anomalies. 
 

 

 

If the Euro having that insane 4-5 passage is right this winter could very well be over. It basically starts it around 1/12.  So figure you’re toast through 2/1 minimum if it’s that strong of a wave.  My hunch though is that it won’t verify anything like that 

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17 minutes ago, SnowGoose69 said:

If the Euro having that insane 4-5 passage is right this winter could very well be over. It basically starts it around 1/12.  So figure you’re toast through 2/1 minimum if it’s that strong of a wave.  My hunch though is that it won’t verify anything like that 

I try to go more by the actual VP anomalies especially with the GFS. The GFS can really struggle with those RMM diagrams. The Euro, CMC, and GFS all get the forcing over to phase 4-5 in early January. So with the lag, the MJO 4-5 influence about a week later. The ultimate amplitude of the MJO 4-5 is still uncertain. But we could be looking at  mild to cold and back to mild temperature swings January 1-15. The exact change dates to be determined later.
 

Forcing shifting to Maritime Continent in early January on the GFS 

83157E55-C132-4C3B-A8D3-400E5F09A1CE.thumb.png.d6738b9e96b91f212bce410e2f278f32.png

 

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today JB mentioned 1936-37 as an analog...what a terrible winter...it was similar to last year...some of the 1930's winters had good Novembers and terrible winters...1931-32...1936-37...even 1938-39 but it did have above average snowfall due to November snows...

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A quick note on the 18z GFS:

The model showed the EPO diving to historic levels toward or below -5.000 in the extended range. That was radically different from the 12z run and the 18z GEFS. It is an outlier with that teleconnection. Hence, its extended range depiction might be a low probability outcome.

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One final thought on the potentially major implications of the recent EPS MJO forecast...

The forecast shows the MJO emerging into Phases 4 and then moving into Phase 5 at a high and increasing amplitude during the extended range:

MJO12282019.jpg

The composite temperature anomalies for December-February MJO phases are below:

MJO-Composites-DJF.jpg

For New York City, the below table shows data for the January 10-20, 1981-2019 period for all dates and for dates when the MJO was in Phases 4 or 5 at an amplitude ranging from 1.000 to 2.000:

MJO12282019-2.jpg

One important caveat: At the current timescale, MJO forecasts have relatively low verification. Therefore, such a scenario is not cast in stone. Greater clarity should develop over the coming week.

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2 hours ago, SnowGoose69 said:

If the Euro having that insane 4-5 passage is right this winter could very well be over. It basically starts it around 1/12.  So figure you’re toast through 2/1 minimum if it’s that strong of a wave.  My hunch though is that it won’t verify anything like that 

in 1978 late January February MJO was in phase 4-5 during those snowstorms - as noted by JB today in his Saturday Summary

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The cold keeps reloading on the GFS after the 5th. What a cold but dry run. There were alot of energy running around on this run but there wouldn't be any storm threat if it's this cold

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4 minutes ago, Snow88 said:

Euro and CMC show a big snowstorm at day 9-10.

Given the extreme AO flip and lag time of the MJO after it passes phase 8-1, I do think some kind of storm is possible.

The AO flip mirrors the early Dec storm that slammed SNE and northern parts of the area. 

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2 minutes ago, SnoSki14 said:

Given the extreme AO flip and lag time of the MJO after it passes phase 8-1, I do think some kind of storm is possible.

The AO flip mirrors the early Dec storm that slammed SNE and northern parts of the area. 

There will be a lag. Every model has a big blast of cold air after the 6th. Gfs has it the whole run.

 

Models also build a ridge in the west.

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