Enso Neutral Conditions Prevails June 2018 – Full-fledged El Nino Ruled Out During Southwest Monsoon 2018

Enso Status on 6th July 2018

Enso Neutral Conditions Prevails June 2018

 

The ONI is based on SST departures from average in the Niño 3.4 region, and is a principal measure for monitoring, assessing, and predicting ENSO. Defined as the three-month running-mean SST departures in the Niño 3.4 region. Departures are based on a set of further improved homogeneous historical SST analyses (Extended Reconstructed SST – ERSST.v5). Explanation about ERSST.v5 is given here.

The SST reconstruction methodology is described in Huang et al., 2015, J. Climate, vol. 28, 911-930.
CPC uses current Climatology based on 1986-2015 which has been changed late last year from base years 1981-2010. Explanation about Climatology base years change is given here.

NOAA Operational Definitions for El Niño and La Niña, El Niño: characterized by a positive ONI greater than or equal to +0.5ºC. La Niña: characterized by a negative ONI less than or equal to -0.5ºC. By historical standards, to be classified as a full-fledged El Niño or La Niña episode, these thresholds must be exceeded for a period of at least 5 consecutive overlapping 3-month seasons.

CPC considers El Niño or La Niña conditions to occur when the monthly Niño3.4 OISST departures meet or exceed +/- 0.5ºC along with consistent atmospheric features. These anomalies must also be forecast to persist for 3 consecutive months.

Last five ONI Index are DJF 2018 -0.9ºC, JFM 2018 -0.8ºC, FMA 2018 -0.6ºC, MAM 2018 -0.4ºC and AMJ 2018 -0.1ºC. Latest Nino 3.4 SST is 0.11ºC and the calculated ONI AMJ 2018 -0.1ºC is negative but in neutral zone. Hence ENSO neutral conditions continues to exist.

La Nina event 2017-18 had officially ended at the end of April 2018 (FMA 2018). ENSO neutral conditions exists since then. The last La Nina event was the second consecutive La Nina event, the first one was 2016-17 La Nina event that ended at the end of January 2017 (NDJ 2017).

 

Latest Oceanic Nino Index Graph Shows ENSO Neutral Conditions Continues AMJ 2018 Season

 

 

The Table below shows the monthly SST of Nino3.4 Region and the Climate adjusted normal SST and SST anomaly for last two years. Climate Base 1986-2015. ERSST.v5

Period    Nino3.4 ClimAdjust
YR   MON  Temp.ºC Temp.ºC ANOM ºC

2016   6   27.70   27.65    0.05
2016   7   26.82   27.26   -0.44
2016   8   26.28   26.91   -0.63
2016   9   26.15   26.80   -0.65
2016  10   25.98   26.75   -0.78
2016  11   25.95   26.75   -0.80
2016  12   26.10   26.65   -0.55
2017   1   26.12   26.45   -0.33
2017   2   26.68   26.66    0.02
2017   3   27.33   27.21    0.12
2017   4   28.04   27.73    0.30
2017   5   28.30   27.85    0.45
2017   6   28.06   27.65    0.41
2017   7   27.54   27.26    0.28
2017   8   26.70   26.91   -0.21
2017   9   26.29   26.80   -0.51
2017  10   26.15   26.75   -0.60
2017  11   25.74   26.75   -1.01
2017  12   25.62   26.65   -1.04
2018   1   25.58   26.45   -0.88
2018   2   25.98   26.66   -0.68
2018   3   26.50   27.21   -0.71
2018   4   27.32   27.73   -0.41
2018   5   27.74   27.85   -0.11
2018   6   27.76   27.65    0.11

 

CPC considers El Niño or La Niña conditions to occur when the monthly Niño3.4 OISST departures meet or exceed +/- 0.5°C along with consistent atmospheric features. These anomalies must also be forecast to persist for 3 consecutive months.

 

Southern Oscillation Index

 

As per BOM, Australia:

The 30-day Southern Oscillation Index (SOI) to 1 July was −6.2, and the 90-day SOI was −0.8. The SOI has been within the neutral range since late April.

 

 

Sustained positive values of the SOI above +7 typically indicate La Niña while sustained negative values below −7 typically indicate El Niño. Values between about +7 and −7 generally indicate neutral conditions.

Recent (preliminary) Southern Oscillation Index values as per The Long Paddock – Queensland Government.

30 Days average SOI was -7.63 at the end of June 2018 and was -6.27 on 6th July 2018 as per The Long Paddock – Queensland Government and 90 Days average SOI was -2.24.

 

SOI Monthly graph up to June 2018 as per The Long Paddock – Queensland Government.

 

 

 

 

 

 

Summary by: Climate Prediction Center / NCEP  Dated 2nd July 2018

ENSO Alert System Status: El Niño Watch

ENSO-neutral conditions are present.*
Equatorial sea surface temperatures (SSTs) are near-to-above average across he east-central Pacific Ocean.
ENSO-neutral is favored through Northern Hemisphere summer 2018, with the chance for El Niño increasing to 50% during fall, and ~65% during winter 2018-19.

* Note: These statements are updated once a month (2nd Thursday of each month) in association
with the ENSO Diagnostics Discussion, which can be found by clicking here.

 

As per BOM -Australia 3rd July 2018

ENSO outlooks

All earlier updates are listed below:

Click here for Update “Weak La Nina Exists Till The End Of April 2018”

Click here for Update “Full Fledged La Nina Event Has Developed At The End Of March 2018”

Click here for Update “La Nina Event 2017-18 Expected To Commence At The End Of March”

Click here for Update “Three Consecutive 3-Monthly Seasons Have Oni -0.5ºC Or Below”