Jump to content
  • Member Statistics

    17,502
    Total Members
    7,904
    Most Online
    Weathernoob335
    Newest Member
    Weathernoob335
    Joined

Weak La Nina Winter


Recommended Posts

  • Replies 469
  • Created
  • Last Reply

December conditions in Nino 3.4, Nino 3, Nino 1.2 were a good match for a blend of 1967, 2005, 2005, 2007. If you blend those years, it isn't a terrible match nationally for December (Nino 1.2, 3.4, 4 is better for national conditions anyway), and you have a lot of pretty warm waters by the US.

Winter 1967-68 was cooler than normal in 3.4, but very cold in Nino 1.2, so it had a very positive Modoki value, which is unusual in years when Nino 3.4 is cold. The 2017-18 imbalance between 3.4 and 1.2 isn't as great as that year, and diminishing somewhat but its useful for blending. I like that blend because something about it is similar in the Atlantic too, you had a major hurricane hit Texas in 1967, the big hurricane season in 2005, and then 2007 had similar sea-ice in Summer to this year. When Beulah hit in 1967, parts of TX had 27 inches of rain (half of Harvey in half the time), and I think super heavy rains in TX in the Summer have some kind of effect on the strength of the subtropical ridge for a long time.

This is on ERSST V.5 - on different data sets 1967 (x5), 1975 (x1), 2005 (x1), 2007 (x3) works pretty well too.

Dec Nino 3.4 Nino 3 Nino 1.2
1967 25.95 23.99 20.97
2005 25.68 24.00 21.89
2007 25.01 23.57 21.15
2005 25.68 24.00 21.89
Mean 25.58 23.89 21.48
2017 25.62 24.02 21.44

I've been looking hard at Spring 1951 too - the dryness (0.04" in Oct-Dec 2017 here, 0.01" in Oct-Dec 1950) with a very hot Nov+Dec here is similar to 1950. If you want to see a batsh-t crazy pattern, look at March 1951.

Link to comment
Share on other sites

1932-33 had similar dryness nationally to this winter, although it was much colder in the West (it was a volcanic-cold neutral). I'm not surprised that 90% of the lower-48 is drier than normal so far. We're actually drier than 1932-33 so far, which is not good as that was one of the winters that triggered the Dust Bowl. Still expecting some turn around in the West toward wetter conditions over the second half of winter. California is actually 5"+ below normal in places so far (3mm/day * 45 days).

jVPOesc.png

Link to comment
Share on other sites

On 1/18/2018 at 3:51 AM, raindancewx said:

1932-33 had similar dryness nationally to this winter, although it was much colder in the West (it was a volcanic-cold neutral). I'm not surprised that 90% of the lower-48 is drier than normal so far. We're actually drier than 1932-33 so far, which is not good as that was one of the winters that triggered the Dust Bowl. Still expecting some turn around in the West toward wetter conditions over the second half of winter. California is actually 5"+ below normal in places so far (3mm/day * 45 days).

jVPOesc.png

There is a bit of correlation, but a lot of the east doesn't match up, and with the current pattern change, things should start to improve out west and in the midwest as well.

Link to comment
Share on other sites

Yep. The winter isn't over yet either, but for an ancient year, its not terrible. I only gave it 1/10th weight anyway.

The main similarity in that year to this year is it has the warm anomalies in the Atlantic north of the cold anomalies in the Atlantic, which has some relationship to precipitation in the West.

cdas-sflux_ssta_global_1.png

Link to comment
Share on other sites

18 minutes ago, AfewUniversesBelowNormal said:

The La Nina is falling apart in the west. it may cold pulse again but it will less than before and followed by a warm up probably above 0.0

I would be careful here, the SOI shot through the roof over the last week, would be indicative of strengthening not weakening with the La Nina.

Link to comment
Share on other sites

Using the 1950-2000 base period from the extended data set NOAA has for Nino 3.4/Nino 1.2, I think NDJ ends up around -0.80C in Nino 3.4, Nino 1.2 around -1.10C.

Last year, against that base period was -0.49C in 3.4, and +0.09C in NDJ, and both warmed a lot in DJF.

I'm hoping we get some last second warming in both - I find hand-blending Nino 1.2, Nino 3.4, for NDJ, with annualized solar analogs produces around a 0.65-r-squared relationship with Spring precipitation in my area. Super dry Springs tend to be very cold in Nino 1.2, Nino 3.4, with low solar activity. The relationship is based on 1987-2016, the further back you go the harder it gets to recreate years. The blend I'm using (-0.8C, -1.1C, 18 sunspots July-Jun) implies 0.96" precipitation here for March-May, which is close to 40% below normal.

My hunch at this point is Nino 3 stays in La Nina conditions the longest, with the event rotting away on both sides pretty rapidly in March/April. 

Link to comment
Share on other sites

January 2018 MJO looks like a blend of 1978, 1986, 1989, 1990 to me. Those years overall had a start in phase two, with February starting around 6/7, and they had no "neutral" MJO conditions. The timing of the phases is too early in those years, but if you add a week, its pretty spot on nationally. January looks pretty warm nationally on the blend, suspect it won't be too far off for Jan 7-Feb 5 or so. I gave Jan 1986 the most weight, as it was a near-Nina in DJF, with low solar, and started in phase two in January. The low-solar years seem to have slower MJO propagation, so the speed is most similar to 1986 too.

ArNLqeb.png

DUH9E_CV4AAeFH2.jpg

Link to comment
Share on other sites

Weakening
                Nino1+2      Nino3        Nino34        Nino4
 Week          SST SSTA     SST SSTA     SST SSTA     SST SSTA 
 01NOV2017     20.4-0.8     24.4-0.6     26.3-0.4     28.7 0.1
 08NOV2017     20.2-1.2     23.8-1.2     25.6-1.1     28.3-0.3
 15NOV2017     20.6-1.0     23.8-1.1     25.6-1.1     28.2-0.4
 22NOV2017     20.6-1.2     23.9-1.1     25.9-0.8     28.5-0.1
 29NOV2017     20.8-1.3     23.9-1.1     25.9-0.7     28.5 0.0
 06DEC2017     20.8-1.6     24.1-1.0     25.7-0.8     28.2-0.3
 13DEC2017     21.3-1.3     24.0-1.1     25.8-0.8     28.1-0.3
 20DEC2017     21.6-1.4     23.8-1.4     25.6-1.0     28.1-0.3
 27DEC2017     22.1-1.3     24.4-0.9     26.0-0.6     28.2-0.2
 03JAN2018     22.9-0.8     24.0-1.4     25.8-0.8     28.3-0.1
 10JAN2018     23.3-0.9     24.3-1.3     25.6-0.9     28.2-0.1
 17JAN2018     23.9-0.6     24.7-0.9     26.0-0.6     27.9-0.3

 

GgoUXXp.png

Link to comment
Share on other sites

In the weekly era here is a look back at how cold the regions were in cold ENSO winters in the same time frame as the most recent week:

                       Nino1+2    Nino3         Nino34         Nino4

                     SST SSTA   SST SSTA  SST SSTA  SST SSTA

 17JAN2018     23.9-0.6     24.7-0.9     26.0-0.6     27.9-0.3
 18JAN2017     26.2 1.6     25.8 0.1     26.4-0.2     28.1-0.1
 15JAN2014     25.0 0.6     25.2-0.4     25.9-0.7     28.0-0.3
 16JAN2013     24.1-0.4     25.0-0.6     26.0-0.6     28.1-0.2
 18JAN2012     24.0-0.6     24.9-0.8     25.4-1.2     27.1-1.2
 19JAN2011     24.2-0.5     24.4-1.3     25.0-1.6     26.7-1.6
 14JAN2009     24.0-0.3     24.8-0.8     25.4-1.1     27.4-0.9
 16JAN2008     24.1-0.4     24.0-1.6     24.6-2.0     26.6-1.7
 18JAN2006     24.3-0.2     24.8-0.9     25.5-1.1     27.6-0.7
 16JAN2002     23.5-1.0     25.0-0.7     26.4-0.1     28.9 0.6
 17JAN2001     23.7-0.8     25.1-0.6     25.8-0.8     27.5-0.8
 19JAN2000     23.7-0.9     24.0-1.7     24.8-1.8     26.9-1.4
 20JAN1999     23.3-1.4     24.5-1.3     25.0-1.6     26.4-1.8
 15JAN1997     23.6-0.8     24.6-1.0     25.8-0.7     28.4 0.1
 17JAN1996     24.0-0.5     25.2-0.5     25.9-0.7     27.8-0.5
 

It looks like 2012-13 right now. ONI for 2012-13 got to near-Nina conditions (-0.4C) in DJF 2012-13. The 2013-14 look was more of a Modoki-cold Neutral. 

 17JAN2018     23.9-0.6     24.7-0.9     26.0-0.6     27.9-0.3

 15JAN1997     23.6-0.8     24.6-1.0     25.8-0.7     28.4 0.1

 15JAN1997     23.6-0.8     24.6-1.0     25.8-0.7     28.4 0.1
 17JAN1996     24.0-0.5     25.2-0.5     25.9-0.7     27.8-0.5

 16JAN2013     24.1-0.4     25.0-0.6     26.0-0.6     28.1-0.2

The blend of 1995-96, 1996-97, 1996-97, 2012-12 gives you -0.6 in Nino 1.2 (correct), -0.8 in Nino 3 (close), -0.7 in Nino 3.4 (close), and -0.1 in Nino 4 (close)

 

Link to comment
Share on other sites

The main 'typical' Nina effects have been a warm SW and a dry subtropical jet this winter, although the STJ position is more similar to a Neutral year I'd argue. I had the East +0 to +2 for DJF highs against 1951-2010, except in FL, which looks OK at the moment.

The subsurface + MJO movement sort of like 2006 right now, but a month ahead, with less cold in the East and less heat in the West.

If the warm up Tropical Tidbits is showing shows up in the weeklies on Monday, the peak of this event was probably -0.9C in an ONI sense. NDJ looks -0.8 or so. The raw numbers for last NDJ were -0.68C, my best guess for this NDJ is -0.85C.

DUbpr9bUQAAp2F5.jpg:large

 

Link to comment
Share on other sites

Less subsurface cold waters to sustain the Nina in 3.4 each week. Also, the warm waters below the surface split this week, some went toward Nino 1.2 for the first time, and others re-consolidated to the West. With the cold v. warm anomalies about even below 3.4 now, would expect ONI to get to near 0 around April in Nino 3.4, but remain pretty healthy in Nino 1.2. There really hasn't been a big decline in the unusually cold subsurface waters east of 100W in the past two months.

vvpnH7Z.png

                Nino1+2      Nino3        Nino34        Nino4
 Week          SST SSTA     SST SSTA     SST SSTA     SST SSTA
 27DEC2017     22.1-1.3     24.4-0.9     26.0-0.6     28.2-0.2
 03JAN2018     22.9-0.8     24.0-1.4     25.8-0.8     28.3-0.1
 10JAN2018     23.3-0.9     24.3-1.3     25.6-0.9     28.2-0.1
 17JAN2018     23.9-0.6     24.7-0.9     26.0-0.6     27.9-0.3
 24JAN2018     24.0-0.9     24.7-1.1     25.9-0.7     27.8-0.4

Still kind of east-central based at the surface. Nino 1.2 departure hasn't been under -0.9C since December.

 

Link to comment
Share on other sites

The Canadian will be out tomorrow. Will be interesting to see how it has the event evolving with another month of data.

The MJO keeps verifying at higher amplitude than the ECMF shows, think it has a real shot at phase two around March 1st, its been hitting the same phases 50-55 days later lately. Was in two for from Dec 29 to Jan 9, which implies Feb 19 to Mar 5 for reaching phase two again, if the magnitude remains high. Phase two in March is cold/stormy in the SW, and a violent tornado pattern for the Central US if we make it to two in March. Kind of like a blend of the European, the red line on the Euro image is what I'm expecting currently.

https://journals.ametsoc.org/doi/abs/10.1175/MWR-D-12-00173.1

A census of events shows that violent tornado outbreaks during March–April–May (MAM) are more than twice as frequent during phase 2 of the Real-time Multivariate MJO (RMM) index as during other phases or when the MJO was deemed inactive

0IH5gLU.png

Link to comment
Share on other sites

http://www.cpc.ncep.noaa.gov/products/analysis_monitoring/ocean/index/heat_content_index.txt
Equatorial Upper 300m temperature Average anomaly based on 1981-2010 Climatology (deg C)
YR    MON   130E-80W   160E-80W   180W-100W 
2017    9    -0.45     -0.57      -0.79
2017   10    -0.54     -0.77      -0.97
2017   11    -0.41     -0.65      -0.84
2017   12    -0.31     -0.54      -0.75
2018    1     0.01     -0.17      -0.16
Link to comment
Share on other sites

SOI is around -20 for Feb 1-3, after the spike to +9 for January.

The Nina is in some trouble, as these reversed/weakened trades will be happening as the warm water continues to surface around Nino 4 and the western part of Nino 3.4. 

SST figures for January, and Nov-Jan should be out within a week. 

Link to comment
Share on other sites

http://origin.cpc.ncep.noaa.gov/products/analysis_monitoring/ensostuff/ONI_v5.php

ONI is in for NDJ: -1.0C. The "de-trended" anomaly is against 26.62C according to this - http://www.cpc.ncep.noaa.gov/products/analysis_monitoring/ensostuff/detrend.nino34.ascii.txt

February came in at -0.9C, the peak was -1.04C for December. Against 1951-2000, NDJ is -0.8C, so even historically its a pretty healthy peak.

Nino 1.2, 3, 4 not in yet. Likely will be later today. Will edit this once they are.

Nino 1.2 came in at 23.32C for January. On the ERSST V.5 data set, that is the coldest January since 1981 (close to 40 years!) for Nino 1.2. Nino 1.2 is really the story of this event, Nino 3.4 isn't particularly impressive.

 

Link to comment
Share on other sites

                Nino1+2      Nino3        Nino34        Nino4
 Week          SST SSTA     SST SSTA     SST SSTA     SST SSTA
 03JAN2018     22.9-0.8     24.0-1.4     25.8-0.8     28.3-0.1
 10JAN2018     23.3-0.9     24.3-1.3     25.6-0.9     28.2-0.1
 17JAN2018     23.9-0.6     24.7-0.9     26.0-0.6     27.9-0.3
 24JAN2018     24.0-0.9     24.7-1.1     25.9-0.7     27.8-0.4
 31JAN2018     24.4-0.9     24.8-1.2     25.8-0.9     27.7-0.5

WEe6KYJ.png

That little blob of warm water in Nino 3 isn't too far away from the surface now, and with most of the subsurface cold used up outside Nino 1.2, it should be able to do some damage to the Nina in the coming weeks. In an SST sense, this event should remain in place until April. The SOI crash to -20.3 for Feb 1-5 means we're 65% favored for an SOI crash of at least 9 from December. Odds are based on 1932-2017 February SOI readings >=4.4 out of all February SOI readings.

Strongly negative SOI crashes favor precipitation in the SW quite strongly, with correlations up to 0.7 in Arizona, Nevada, and Western NM.

QBQ6hrE.png

This is what I got for SOI odds using observed Feb SOI readings plugged in for the remaining 23-days of February. SOI drop from January is in (). Biggest drop since 1931 from Jan to Feb is -30.7 in 2005, during the 2004-05 El Nino.

5th %  = -20.53 (-29.4)
10th % = -16.76 (-25.7)
20th % = -10.18 (-19.1)
50th % = -3.90  (-12.8)
80th % = +2.96 (-7.0)
90th % = +7.48 (-1.5)
95th % = +9.32 (+0.4)

Link to comment
Share on other sites

SOI is now -22.5 for Feb 1-8. The GFS as of when I looked on 2/6, was implying the negative burst continues into at least 2/15 (see image from 2/6). We're up to about a 23% chance of a 20 point SOI drop, which is 16-17x more likely than usual. My odds are based on plugging in historical February SOI numbers from 1932-2017 for the remainder of February, blended with the Feb 1-8 observations and dividing the total by 28. The plug-in method is up to a 15.6 drop from Dec-Jan as the median through 2/8.

ljnfNOq.png

Models are hinting at major precipitation in the SW in the long-range, possibly in recognition of the drop?

Link to comment
Share on other sites

If an El Nino does develop, its worth noting that some of the bigger El Ninos (peak trimester >1.5) have seen weak El Ninos only three years after their conclusion:

1965-66:  1968-60

1991-92:  1994-95

NOAA/CPC has been centering ONI values for each ENSO event in its 30-year "climate", so the +2.6 peak or whatever for the 2015-16 Nino is based on 1986-2015 currently. When they have 2001-2030 means and if Nino 3.4 averages have increased a bit, the peak will probably be like the 1965-66 event, at +2.0 or so given that both the strong warm/cold events have been peaking in Fall over the past couple decades.

 

Link to comment
Share on other sites

Archived

This topic is now archived and is closed to further replies.

  • Recently Browsing   0 members

    • No registered users viewing this page.

×
×
  • Create New...