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I'm beyond mystified why a number of mets have written off the La Nina possibility this winter.  The last week has featured a full blown Nina atmosphere with Nino 3.4 currently at weak Nina levels.  A huge trade wind burst has been ongoing for the past week or so which will only help our chances.  Here is a rundown of the ENSO vital statistics.
 
Nino 3.4 - Below -0.5
 
OLR (5N to 5S / 160W to 160E) - moderate positive anoms (ninaish)
 
30 day SOI = +11 (ninaish)
 
SOI* (September to date) = positive (ninaish)
 
NOI (September to date) = positive (ninaish)
 
Current MJO = octant 4 (ninaish)
 
200mb zonal winds = positive (ninaish)
 
Subsurface ocean temps under the ENSO regions also remain cold.
 
ENSO SST's will only drop with these number.  Feel free to post any ENSO related graphics you may have.

Death To Warm Anomalies!

 

Winter 2021-22 stats

 

Total Snowfall = 0.0"

Day with 1" or more snow depth = 0

Total Hail = 0.0"

Coldest Low = 29

Lows 32 or below = 6

Highs 32 or below = 0

Lows 20 or below = 0

Highs 40 or below = 0

 

 

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Here is the last week... that huge trade wind burst did nothing much at all.   In fact it looks like it warmed a little overall. 

 

http://coralreefwatch.noaa.gov/satellite/bleaching5km/images_current/cur_b05kmnn_ssttrend_007d_large.gif

**REPORTED CONDITIONS AND ANOMALIES ARE NOT MEANT TO IMPLY ANYTHING ON A REGIONAL LEVEL UNLESS SPECIFICALLY STATED**

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Published: September 15, 2016

A monthly summary of the status of El Niño, La Niña, and the Southern Oscillation, or ENSO, based on the NINO3.4 index (120-170W, 5S-5N)

Use the navigation menu on the right to navigate to the different forecast sections

During mid-September 2016 the tropical Pacific SST anomaly was close to -0.5C, the weak La Niña threshold. However, not all of the atmospheric variables support weak La Niña conditions. Although the upper level winds in the tropical Pacific are somewhat suggestive of La Niña, the lower level winds remain near average. The Southern Oscillation index and the pattern of cloudiness and rainfall in the equatorial Pacific are somewhat suggestive of weak La Niña conditions, but could also be interpreted as being in the cool-neutral range. The collection of ENSO prediction models indicates SSTs hovering at levels near borderline La Niña during fall, then weakening to cool-neutral in late fall and into winter.

 

http://iri.columbia.edu/wp-content/uploads/2016/09/figure4.gif

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I'm hoping somebody will post the graphs that show daily SST anomalies for the ENSO regions.  I have been able to find those.

Death To Warm Anomalies!

 

Winter 2021-22 stats

 

Total Snowfall = 0.0"

Day with 1" or more snow depth = 0

Total Hail = 0.0"

Coldest Low = 29

Lows 32 or below = 6

Highs 32 or below = 0

Lows 20 or below = 0

Highs 40 or below = 0

 

 

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Published: September 15, 2016

A monthly summary of the status of El Niño, La Niña, and the Southern Oscillation, or ENSO, based on the NINO3.4 index (120-170W, 5S-5N)

Use the navigation menu on the right to navigate to the different forecast sections

During mid-September 2016 the tropical Pacific SST anomaly was close to -0.5C, the weak La Niña threshold. However, not all of the atmospheric variables support weak La Niña conditions. Although the upper level winds in the tropical Pacific are somewhat suggestive of La Niña, the lower level winds remain near average. The Southern Oscillation index and the pattern of cloudiness and rainfall in the equatorial Pacific are somewhat suggestive of weak La Niña conditions, but could also be interpreted as being in the cool-neutral range. The collection of ENSO prediction models indicates SSTs hovering at levels near borderline La Niña during fall, then weakening to cool-neutral in late fall and into winter.

 

 

 

I actually don't totally buy the bolded statement.  The 200mb, 850mb, and surface (SOI) are all quite Ninaish.  That doesn't really translate to no anomalous trade winds at the surface.  The warming being shown on the graph is not climatologically favored.  Usually ENSO anomalies reach their max during winter.

Death To Warm Anomalies!

 

Winter 2021-22 stats

 

Total Snowfall = 0.0"

Day with 1" or more snow depth = 0

Total Hail = 0.0"

Coldest Low = 29

Lows 32 or below = 6

Highs 32 or below = 0

Lows 20 or below = 0

Highs 40 or below = 0

 

 

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Here is the last week... that huge trade wind burst did nothing much at all.   In fact it looks like it warmed a little overall. 

 

 

Give it a few more days.  The subsurface is still cold and the trades favor upwelling of the cold water.

Death To Warm Anomalies!

 

Winter 2021-22 stats

 

Total Snowfall = 0.0"

Day with 1" or more snow depth = 0

Total Hail = 0.0"

Coldest Low = 29

Lows 32 or below = 6

Highs 32 or below = 0

Lows 20 or below = 0

Highs 40 or below = 0

 

 

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Give it a few more days.  The subsurface is still cold and the trades favor upwelling of the cold water.

 

 

All sort of meaningless for us.   Cold neutral or weak Nina is all about the same and offers good prospects for us.   Not worth worrying about at this point... just have to see how it plays out. 

**REPORTED CONDITIONS AND ANOMALIES ARE NOT MEANT TO IMPLY ANYTHING ON A REGIONAL LEVEL UNLESS SPECIFICALLY STATED**

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Yea. Probably not a big difference if ONI comes in at 0.3 or 0.6

 

Probably true.  Oddly the CPC has us EC for the winter now instead of cold though.

Death To Warm Anomalies!

 

Winter 2021-22 stats

 

Total Snowfall = 0.0"

Day with 1" or more snow depth = 0

Total Hail = 0.0"

Coldest Low = 29

Lows 32 or below = 6

Highs 32 or below = 0

Lows 20 or below = 0

Highs 40 or below = 0

 

 

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Probably true.  Oddly the CPC has us EC for the winter now instead of cold though.

 

 

Who cares?   Those are just formulas.   You can't really predict a neutral type winter.    But it probably offers us the best chance at snow and cold at least at some point during the winter.

**REPORTED CONDITIONS AND ANOMALIES ARE NOT MEANT TO IMPLY ANYTHING ON A REGIONAL LEVEL UNLESS SPECIFICALLY STATED**

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Looks like a Nina to me.  The reanalysis really gives a good picture of what's actually going on.  It's also worth noting the 2 month running average is below -0.5 for Nino 3.4.  It's likely this will verify as a Nina or at least very close to it.  Sometimes I think the CPC requirement of five consecutive tri monthly averages is too strict.  Under that criteria 2008-09 didn't qualify as a Nina even though it had one monthly average at -1.0.

 

 

post-222-0-06164500-1474256706_thumb.gif

Death To Warm Anomalies!

 

Winter 2021-22 stats

 

Total Snowfall = 0.0"

Day with 1" or more snow depth = 0

Total Hail = 0.0"

Coldest Low = 29

Lows 32 or below = 6

Highs 32 or below = 0

Lows 20 or below = 0

Highs 40 or below = 0

 

 

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Looks like a Nina to me. The reanalysis really gives a good picture of what's actually going on. It's also worth noting the 2 month running average is below -0.5 for Nino 3.4. It's likely this will verify as a Nina or at least very close to it. Sometimes I think the CPC requirement of five consecutive tri monthly averages is too strict. Under that criteria 2008-09 didn't qualify as a Nina even though it had one monthly average at -1.0.

So neutral to weak nina?

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I am unsure whether this will officially qualify as a nina but in my mind the atmosphere is already behaving like a weak nina and that is what counts, not SSTAs. 

 

Very good point.

Death To Warm Anomalies!

 

Winter 2021-22 stats

 

Total Snowfall = 0.0"

Day with 1" or more snow depth = 0

Total Hail = 0.0"

Coldest Low = 29

Lows 32 or below = 6

Highs 32 or below = 0

Lows 20 or below = 0

Highs 40 or below = 0

 

 

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Yeah, I'm not quite sure why anyone is in such a panic over these small details. Who cares whether it's an official weak nina or cold neutral year... it doesn't make much difference.

Nope, I don't think it does either. What should be of a little more interest is where the coldest and warmest anomalies are though. Negative anomalies will be central pacific this year. 

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Illustration of how this fledgling Nina has shifted to being west-based and how the GOA has warmed dramatically...

 

June 1st:

 

http://www.ospo.noaa.gov/data/sst/anomaly/2016/anomnight.6.2.2016.gif

 

 

Today:

 

http://www.ospo.noaa.gov/data/sst/anomaly/2016/anomnight.9.19.2016.gif

**REPORTED CONDITIONS AND ANOMALIES ARE NOT MEANT TO IMPLY ANYTHING ON A REGIONAL LEVEL UNLESS SPECIFICALLY STATED**

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The PDO has definitely dropped in response to the stronger NPAC high. Circulation is definitely more Niña-esque, with help from the +QBO.

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MEI matters.

This is from the wiki page on how it is made:

 

MEI is determined as the first principal component of six different parameters: sea level pressure, zonal and meridional components of the surface wind, sea surface temperature, surface air temperature and cloudiness using data from the International Comprehensive Ocean-Atmosphere Data Set (ICOADS ).

 

This is a longer and more complete way of saying what I said. So yes, SSTA's are not meaningless, but the MEI uses 5 other parameters in its calculation along with SSTs and is therefore a much more comprehensive view of the system as it considers the atmosphere as well. And as you know, SSTAs are a reflection of longer term atmospheric/oceanic processes. Although SSTAs influence convective anomalies down there (important), the SSTAs themselves are a result of whatever pattern is in play, and therefore by themselves they don't mean a lot as I originally said. 

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Is that why we're about to get a death ridge?

The +QBO helps you guys during the winter, in that it favors poleward NPAC anticyclones (stronger Pacific blocking, reduced zonal component). So while you'll occasionally wind up underneath the aforementioned ridge, having the amplified ridge is a necessary component for true Arctic air, as opposed to a flat/equatorward ridge that'd lead to something along the lines of 2007/08.

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This is from the wiki page on how it is made:

 

MEI is determined as the first principal component of six different parameters: sea level pressure, zonal and meridional components of the surface wind, sea surface temperature, surface air temperature and cloudiness using data from the International Comprehensive Ocean-Atmosphere Data Set (ICOADS ).

 

This is a longer and more complete way of saying what I said. So yes, SSTA's are not meaningless, but the MEI uses 5 other parameters in its calculation along with SSTs and is therefore a much more comprehensive view of the system as it considers the atmosphere as well. And as you know, SSTAs are a reflection of longer term atmospheric/oceanic processes. Although SSTAs influence convective anomalies down there (important), the SSTAs themselves are a result of whatever pattern is in play, and therefore by themselves they don't mean a lot as I originally said.

Yep. :)

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Lighten up??? Have you seen today's models???

Did you really find my two posts this morning that offensive? Or do you just wish I was more upset? :lol:

 

The ridge looks fairly short lived. It did kind of suck to lose that potential cool shot at the end of the month, though. That thing looked pretty.

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Jim and others have noted the unusually high surface pressure over the NE Pacific this past summer. This is backed up by the NPI (North Pacific Index), which recorded monthly readings of 1017.59, 1020.14, and 1018.83 in June, July, and August respectively.

 

What do those numbers mean?

 

Combined, the NPI was the highest for any summer on record (back to 1900). The closest was 1915.

 

The June number was highest since 1998. The July number was the highest since 1922. The August number was the highest since 1938.

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Is that why we're about to get a death ridge?

 

No way to be sure of that yet.

Death To Warm Anomalies!

 

Winter 2021-22 stats

 

Total Snowfall = 0.0"

Day with 1" or more snow depth = 0

Total Hail = 0.0"

Coldest Low = 29

Lows 32 or below = 6

Highs 32 or below = 0

Lows 20 or below = 0

Highs 40 or below = 0

 

 

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Jim and others have noted the unusually high surface pressure over the NE Pacific this past summer. This is backed up by the NPI (North Pacific Index), which recorded monthly readings of 1017.59, 1020.14, and 1018.83 in June, July, and August respectively.

 

What do those numbers mean?

 

Combined, the NPI was the highest for any summer on record (back to 1900). The closest was 1915.

 

The June number was highest since 1998. The July number was the highest since 1922. The August number was the highest since 1938.

 

1915...doesn't get much better than that.  Out of the 4 years you mentioned there 3 had major Arctic blasts that winter.  1915-16 and 1922-23 were top tier winters.

 

I actually went to the trouble of making a table of NPI anomalies.  Much more useful than the actual numbers IMO.

Death To Warm Anomalies!

 

Winter 2021-22 stats

 

Total Snowfall = 0.0"

Day with 1" or more snow depth = 0

Total Hail = 0.0"

Coldest Low = 29

Lows 32 or below = 6

Highs 32 or below = 0

Lows 20 or below = 0

Highs 40 or below = 0

 

 

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Share on other sites

Jim and others have noted the unusually high surface pressure over the NE Pacific this past summer. This is backed up by the NPI (North Pacific Index), which recorded monthly readings of 1017.59, 1020.14, and 1018.83 in June, July, and August respectively.

 

What do those numbers mean?

 

Combined, the NPI was the highest for any summer on record (back to 1900). The closest was 1915.

 

The June number was highest since 1998. The July number was the highest since 1922. The August number was the highest since 1938.

Yeah, not only that, but the ENSO CP anomaly (reflective of wind stress forcing) was/is more reminiscent of a very strong Niña. The SSTs seem to be lagging, as it looks like the atmosphere has its mind made up.

 

http://www.esr.org/enso_index.html

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Yeah, not only that, but the ENSO CP anomaly (reflective of wind stress forcing) was/is more reminiscent of a very strong Niña. The SSTs seems to be lagging:

 

http://www.esr.org/enso_index.html

 

 

Maybe can get a lovely 1998-99 repeat without the strong Nina!  

**REPORTED CONDITIONS AND ANOMALIES ARE NOT MEANT TO IMPLY ANYTHING ON A REGIONAL LEVEL UNLESS SPECIFICALLY STATED**

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The +QBO helps you guys during the winter, in that it favors poleward NPAC anticyclones (stronger Pacific blocking, reduced zonal component). So while you'll occasionally wind up underneath the aforementioned ridge, having the amplified ridge is a necessary component for true Arctic air, as opposed to a flat/equatorward ridge that'd lead to something along the lines of 2007/08.

 

Well said.  It's pretty common for our best NPAC blocks to come on the heels of a death ridge near the West Coast.

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Death To Warm Anomalies!

 

Winter 2021-22 stats

 

Total Snowfall = 0.0"

Day with 1" or more snow depth = 0

Total Hail = 0.0"

Coldest Low = 29

Lows 32 or below = 6

Highs 32 or below = 0

Lows 20 or below = 0

Highs 40 or below = 0

 

 

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Maybe can get a lovely 1998-99 repeat without the strong Nina!

Lol, that would be horrible. I do think the entire country went into the freezer for a few weeks in January of 1999, but that was an exception to the rule.

 

Good news is this year, we have a +QBO, weak solar, and a more favorable IO/WPAC.

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Lol, that would be horrible. I do think the entire country went into the freezer for a few weeks in January of 1999, but that was an exception to the rule.

 

Good news is this year, we have a +QBO, weak solar, and a more favorable IO/WPAC.

 

We had a pretty major blast in December 1998, but the rest of the winter was awful.

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Death To Warm Anomalies!

 

Winter 2021-22 stats

 

Total Snowfall = 0.0"

Day with 1" or more snow depth = 0

Total Hail = 0.0"

Coldest Low = 29

Lows 32 or below = 6

Highs 32 or below = 0

Lows 20 or below = 0

Highs 40 or below = 0

 

 

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1915...doesn't get much better than that.  Out of the 4 years you mentioned there 3 had major Arctic blasts that winter.  1915-16 and 1922-23 were top tier winters.

 

I actually went to the trouble of making a table of NPI anomalies.  Much more useful than the actual numbers IMO.

 

Yeah, I wish there was a monthly anomaly series out there for the NPI. If there is, I haven't seen it.

 

If the NPI stays high through October, that's a very good sign.

 

Here's the Octobers (excluding strong ENSO years) since 1950 with 1014+ NPI: 1956, 1958, 1961, 1964, 1966, 1970, 1971, 1981, 1983, 1985, 1989, 1990, 1996, 2006, and 2008. Most of the following winters featured quite a bit of blockiness, with some major cold spells across much of the country. 

 

If we narrow it down to +QBO years: 1961, 1966, 1971, 1985, 1990, 2006, and 2008.

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Yeah, I wish there was a monthly anomaly series out there for the NPI. If there is, I haven't seen it.

 

If the NPI stays high through October, that's a very good sign.

 

Here's the Octobers (excluding strong ENSO years) since 1950 with 1014+ NPI: 1956, 1958, 1961, 1964, 1966, 1970, 1971, 1981, 1983, 1985, 1989, 1990, 1996, 2006, and 2008. Most of the following winters featured quite a bit of blockiness, with some major cold spells across much of the country. 

 

If we narrow it down to +QBO years: 1961, 1966, 1971, 1985, 1990, 2006, and 2008.

 

Nice list except for 1966.

 

I have found that strong surface pressure over the NE Pacific in October is perhaps the most important indicator for a cold winter in the NW there is.  I made an index that is a variant of the NPI that looks more specifically at anomalies more in the eastern part of the North Pacific and the correlation is near 100% when dealing with abnormally strong positive anoms.

Death To Warm Anomalies!

 

Winter 2021-22 stats

 

Total Snowfall = 0.0"

Day with 1" or more snow depth = 0

Total Hail = 0.0"

Coldest Low = 29

Lows 32 or below = 6

Highs 32 or below = 0

Lows 20 or below = 0

Highs 40 or below = 0

 

 

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Nice list except for 1966.

 

I have found that strong surface pressure over the NE Pacific in October is perhaps the most important indicator for a cold winter in the NW there is. I made an index that is a variant of the NPI that looks more specifically at anomalies more in the eastern part of the North Pacific and the correlation is near 100% when dealing with abnormally strong positive anoms.

Yeah, I was running some cross-correlations on ESRL tonight and found something similar. The latitude of the NPAC in October is actually a good predictor of the midwinter NPAC state. Much more predictive than I'd originally thought.

 

I also found that an Alaskan vortex during the middle & later portions of October is strongly correlated to reduced NPAC blocking during DJF, so I guess that's something we want to avoid. The correlative signal here falls apart in November, however.

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30 day SOI is up to +13 now.  With another trade wind burst on the way I would presume high SOI will continue for a while.

Death To Warm Anomalies!

 

Winter 2021-22 stats

 

Total Snowfall = 0.0"

Day with 1" or more snow depth = 0

Total Hail = 0.0"

Coldest Low = 29

Lows 32 or below = 6

Highs 32 or below = 0

Lows 20 or below = 0

Highs 40 or below = 0

 

 

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Weatherbell's updated winter forecast:

 

http://www.weatherbell.com/winter-2016-17-forecast

 

I mean, a lot of it is fairly well reasoned. I think they have nailed the jet placement for winter. I wouldn't be surprised to see the PNW overall be about normal or slightly above in the temp department, but have a couple weeks where the temps are in the deep freeze. Fraser Outflow FTW!

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Weatherbell's updated winter forecast:

 

http://www.weatherbell.com/winter-2016-17-forecast

 

I mean, a lot of it is fairly well reasoned. I think they have nailed the jet placement for winter. I wouldn't be surprised to see the PNW overall be about normal or slightly above in the temp department, but have a couple weeks where the temps are in the deep freeze. Fraser Outflow FTW!

 

I'm a bit dubious about their use of 2014-15 and 2015-16 as analogs.  They were both Ninos after all.

Death To Warm Anomalies!

 

Winter 2021-22 stats

 

Total Snowfall = 0.0"

Day with 1" or more snow depth = 0

Total Hail = 0.0"

Coldest Low = 29

Lows 32 or below = 6

Highs 32 or below = 0

Lows 20 or below = 0

Highs 40 or below = 0

 

 

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Share on other sites

Weatherbell's updated winter forecast:

 

http://www.weatherbell.com/winter-2016-17-forecast

 

I mean, a lot of it is fairly well reasoned. I think they have nailed the jet placement for winter. I wouldn't be surprised to see the PNW overall be about normal or slightly above in the temp department, but have a couple weeks where the temps are in the deep freeze. Fraser Outflow FTW!

 

 

So they are directly saying in the first point that the PDO is driving the weather and will result in cold in the Plains and the East.

 

I thought the PDO was a reflection of the pattern... not a driver???

**REPORTED CONDITIONS AND ANOMALIES ARE NOT MEANT TO IMPLY ANYTHING ON A REGIONAL LEVEL UNLESS SPECIFICALLY STATED**

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