\nTitle: “El Ni\u00f1o Ends & First ENSO Neutral Threshold Established End of June 2024 – Full-fledged La Ni\u00f1a As Per NOAA Criteria Not Expected During Indian Southwest Monsoon 2024” Available here<\/a><\/strong><\/em>
\nIn our first post, we highlighted the end of the El Ni\u00f1o phase, with the ENSO conditions transitioning to neutral by the end of June. Based on NOAA criteria, we concluded that a full-fledged La Ni\u00f1a event was unlikely during the Indian Southwest Monsoon of 2024.<\/p>\n
9th August 2024<\/strong> 6th September 2024<\/strong> 23rd October 2024<\/strong> 6th November 2024<\/strong> 6th December 2024<\/strong> To understand why the anticipated La Ni\u00f1a failed to materialize, it’s important to define what constitutes a “fully developed La Ni\u00f1a,” or a “full-fledged La Ni\u00f1a,” based on NOAA\u2019s operational definitions for ENSO (El Ni\u00f1o-Southern Oscillation):<\/p>\n For an event to be classified as a full-fledged<\/em> El Ni\u00f1o or La Ni\u00f1a, the respective ONI threshold must be exceeded for at least five consecutive overlapping 3-monthly seasons.<\/p>\n In the case of the 2024 Indian Summer Monsoon, despite extensive monitoring, a La Ni\u00f1a event never materialized. The required threshold for La Ni\u00f1a, a negative ONI of -0.5\u00baC or lower, was never reached.<\/p>\n ONI Data has been obtained from CPC – NWS – NOAA available here<\/a><\/p>\n As of the end of November 2024, the Oceanic Ni\u00f1o Index (ONI) remains at -0.2\u00b0C, keeping the ENSO-neutral threshold intact for the SON (September-October-November) 2024 season. This marks the sixth consecutive ENSO-neutral condition. To transition into a La Ni\u00f1a state, the ONI would need to drop to at least -0.5\u00b0C during the OND (October-November-December) 2024 season. Specifically, the combined Ni\u00f1o3.4 sea surface temperature (SST) for September, October, and November 2024 must total at least -1.36\u00b0C.<\/p>\n Currently, the Ni\u00f1o3.4 SST is recorded at -0.26\u00b0C for October 2024 and -0.19\u00b0C for November 2024. To meet the necessary three-month total, the SST in December 2024 would need to drop to -0.91\u00b0C. If this occurs, the first La Ni\u00f1a threshold would be met for the OND 2024 season, potentially setting the stage for a fully developed La Ni\u00f1a by April 2025, provided the La Ni\u00f1a thresholds are sustained across all overlapping three-monthly seasons until then.<\/p>\n However, if the Ni\u00f1o3.4 SST does not reach -0.91\u00b0C by December 2024, ENSO-neutral conditions will persist. In that case, the earliest a fully developed La Ni\u00f1a could form would be in May 2025, assuming the necessary three monthly seasons thresholds are met till then.<\/p>\n Based on this analysis and NOAA criteria, a fully developed La Ni\u00f1a is unlikely unless the La Ni\u00f1a threshold is sustained over two to three consecutive seasons in the coming months. It is also possible that the first La Ni\u00f1a threshold may only be exceeded for a period of four or fewer consecutive overlapping three-month seasons, which, historically, would still be considered ENSO-neutral.<\/p>\n How ONI is determined:<\/strong><\/p>\n The ONI is based on SST departures from average in the Ni\u00f1o 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 Ni\u00f1o 3.4 region. Departures are based on a set of improved homogeneous historical SST analyses (Extended Reconstructed SST \u2013 ERSST.v5).<\/p>\n NOAA Operational Definitions for El Ni\u00f1o and La Ni\u00f1a, El Ni\u00f1o: characterized by a positive ONI greater than or equal to +0.5\u00baC. La Ni\u00f1a: characterized by a negative ONI less than or equal to -0.5\u00baC. By historical standards, to be classified as a full-fledged El Ni\u00f1o or La Ni\u00f1a episode, these thresholds must be exceeded for a period of at least 5 consecutive overlapping 3-month seasons.<\/p>\n CPC considers El Ni\u00f1o or La Ni\u00f1a conditions to occur when the monthly Ni\u00f1o3.4 OISST departures meet or exceed +\/- 0.5\u00baC along with consistent atmospheric features. These anomalies must also be forecast to persist for 3 consecutive months.<\/p>\n The\u00a0Climate Prediction Center<\/b>\u00a0(CPC<\/b>) is a United States Federal Agency that is one of the NECP, which are a part of the NOAA<\/p>\n The Table below shows the monthly SST of Nino3.4 Region and the Climate adjusted normal SST and SST anomaly from February 2023. Climate Base 1991-2020. ERSST.v5<\/strong><\/p>\n Indications and analysis of various International Weather\/Climate agencies monitoring Enso conditions is depicted hereunder:<\/strong><\/p>\n ENSO Alert System Status: La Ni\u00f1a Watch<\/strong><\/p>\n ENSO-neutral conditions are present.* Note: 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<\/a>.<\/span><\/p>\n Although the 30 Days average SOI was in neutral zone at +6.96 end of November 2024, today the 5th December 2024 it was in the positive zone at\u00a0+10.95 as per The Long Paddock – Queensland Government and 90 Days average SOI was +4.34 on 5th December 2024.<\/p>\n <\/p>\n <\/p>\n <\/p>\n <\/p>\n <\/p>\n <\/p>\n <\/p>\n","protected":false},"excerpt":{"rendered":" La Ni\u00f1a Threshold Not Yet Reached, ENSO Neutral Conditions Persist: Full-fledged La Nina Requires At Least Five Months Enso Status on 5th December 2024 Analysis & Commentary by Ashok Patel Several international meteorological agencies, including the Indian Meteorological Department and Read More …<\/a><\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"closed","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[1,7],"tags":[],"class_list":["post-34154","post","type-post","status-publish","format-standard","hentry","category-enso","category-ashok-patel-weather"],"_links":{"self":[{"href":"https:\/\/www.gujaratweather.com\/index.php?rest_route=\/wp\/v2\/posts\/34154","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.gujaratweather.com\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.gujaratweather.com\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.gujaratweather.com\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.gujaratweather.com\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=34154"}],"version-history":[{"count":0,"href":"https:\/\/www.gujaratweather.com\/index.php?rest_route=\/wp\/v2\/posts\/34154\/revisions"}],"wp:attachment":[{"href":"https:\/\/www.gujaratweather.com\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=34154"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.gujaratweather.com\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=34154"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.gujaratweather.com\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=34154"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}
\nTitle: “NOAA Criteria Suggest Full-Fledged La Ni\u00f1a Unlikely in 2024 \u2013 Even a Single La Ni\u00f1a Threshold Unlikely During the Indian Southwest Monsoon” Available here<\/a><\/strong><\/em>
\nOur second update reiterated that, according to NOAA criteria, a full-fledged La Ni\u00f1a was unlikely in 2024. We further emphasized that even crossing a single La Ni\u00f1a threshold during the monsoon season seemed improbable.<\/p>\n
\nTitle: “Much-Awaited La Ni\u00f1a Unlikely in 2024; La Ni\u00f1a Threshold Not Expected During Indian Southwest Monsoon”
\nAvailable here<\/a><\/strong><\/em>
\nBy September, our analysis further confirmed that the much-anticipated La Ni\u00f1a event was unlikely to occur, with no indications of reaching the La Ni\u00f1a threshold during the Indian Southwest Monsoon.<\/p>\n
\nTitle: “La Ni\u00f1a Threshold Not Yet Reached: Full-fledged La Ni\u00f1a Unlikely During Indian Winter 2024-25” Available here<\/a><\/strong><\/em>
\nOur fourth update noted that as of September end, the La Ni\u00f1a threshold had still not been reached, suggesting that a full-fledged La Ni\u00f1a event during the Indian Winter of 2024-25 was also unlikely.<\/p>\n
\nTitle: “La Ni\u00f1a Playing Hard Ball: Full-fledged La Ni\u00f1a Unlikely During Indian Winter 2024-25” Available here<\/a><\/strong><\/em>
\nOur fifth post reaffirmed that La Ni\u00f1a conditions were proving elusive. With no clear signals of a La Ni\u00f1a, we maintain that La Nina will not materialize during the Indian Winter 2024-25.<\/p>\n
\nTitle: “ENSO Neutral Conditions Persist: La Ni\u00f1a Threshold Not Yet Reached, Full-fledged La Ni\u00f1a Requires At Least Five Months”\u00a0<\/em>
\nIn our latest update, we report that ENSO neutral conditions are still persisting. Despite the ongoing monitoring, the La Ni\u00f1a threshold has not yet been reached, and we stress that a full-fledged La Ni\u00f1a would require at least five months of sustained La Nina thresh hold conditions once it is reached.<\/p>\nWhat is a Fully Developed La Ni\u00f1a?<\/h3>\n
\n
Latest Oceanic Nino Index Graph Shows Enso Neutral
\nConditions Prevail\u00a0 At The End Of November 2024<\/strong><\/h4>\n![\"\"](\"https:\/\/vmi2318806.contaboserver.net\/wp-content\/uploads\/2024\/12\/ONI_SON_2024-1024x761.jpg\")
<\/a><\/p>\nPeriod Nino3.4 ClimAdjust\r\nYR MON Temp.\u00baC Temp.\u00baC ANOM \u00baC\r\n\r\n\r\n2023 2 26.30 26.76 -0.46\r\n2023 3 27.19 27.29 -0.11\r\n2023 4 27.96 27.83 0.14\r\n2023 5 28.40 27.94 0.46\r\n2023 6 28.57 27.73 0.84\r\n2023 7 28.31 27.29 1.02\r\n2023 8 28.21 26.86 1.35\r\n2023 9 28.32 26.72 1.60\r\n2023 10 28.44 26.72 1.72\r\n2023 11 28.72 26.70 2.02\r\n2023 12 28.63 26.60 2.02\r\n2024 1 28.37 26.55 1.82\r\n2024 2 28.28 26.76 1.52\r\n2024 3 28.42 27.29 1.12\r\n2024 4 28.60 27.83 0.78\r\n2024 5 28.17 27.94 0.24\r\n2024 6 27.91 27.73 0.18\r\n2024 7 27.34 27.29 0.05\r\n2024 8 26.74 26.86 -0.11\r\n2024 9 26.46 26.72 -0.25\r\n2024 10 26.45 26.72 -0.26\r\n2024 11 26.51 26.70 -0.19\r\n<\/pre>\n
Summary by: Climate Prediction Center \/ NCEP \u00a0Dated 2nd December 2024<\/strong><\/h4>\n
\nEquatorial sea surface temperatures (SSTs) are mostly near average in the central and eastern Pacific Ocean.
\nLa Ni\u00f1a is most likely to emerge in October-December 2024 (57% chance) and is expected to persist through January-March 2025.*<\/p>\n<\/h4>\n
Recent (preliminary) Southern Oscillation Index values as per The Long Paddock – Queensland Government.<\/strong><\/h4>\n
![\"\"](\"https:\/\/vmi2318806.contaboserver.net\/wp-content\/uploads\/2024\/12\/Long-Padock-051224-1024x427.png\")
<\/a><\/p>\nAs per BOM \u2013 Australia 23rd November 2024<\/strong><\/h4>\n
\n
\n
![\"\"](\"https:\/\/vmi2318806.contaboserver.net\/wp-content\/uploads\/2024\/12\/20241126.sstOutlooks_nino34.png\")
<\/a><\/p>\n