{"id":247239,"date":"2023-06-09T19:46:44","date_gmt":"2023-06-09T14:16:44","guid":{"rendered":"https:\/\/blog.forumias.com\/?p=247239"},"modified":"2023-06-09T19:46:44","modified_gmt":"2023-06-09T14:16:44","slug":"what-is-the-onset-of-the-monsoon-and-why-the-delayed-onset-is-not-necessarily-bad-news","status":"publish","type":"post","link":"https:\/\/forumias.com\/blog\/what-is-the-onset-of-the-monsoon-and-why-the-delayed-onset-is-not-necessarily-bad-news\/","title":{"rendered":"What is the \u2018onset\u2019 of the monsoon, and why the delayed onset is not necessarily bad news"},"content":{"rendered":"\n

Source:\u00a0<\/b>The post is based on the article\u00a0\u201cWhat is the \u2018onset\u2019 of the monsoon, and why the delayed onset is not necessarily bad news\u201d<\/b> published in the Indian Express <\/b>on\u00a09th <\/strong>June\u00a0<\/b>2023<\/b><\/p>\n

What is the News?<\/span><\/h2>\n

According to the India Meteorological Department (IMD), the southwest monsoon onset over Kerala this year will be delayed.<\/p>\n

What is meant by the \u201conset of the monsoon\u201d over the Kerala coast?<\/h2>\n

The onset of the monsoon over Kerala signals the beginning of the four-month (June-September) southwest monsoon season. During the southwest monsoon, India gets more than 70% of its annual rainfall. It is an important day in the economic calendar of the country.<\/p>\n

\u2018Onset\u2019 is a technical expression with a specific definition and the IMD does not officially declare onset until certain prescribed conditions are met. The onset does not mean the first rain of the season. That can start happening in certain places even before the onset is declared.<\/p>\n

The normal date of the onset of the monsoon over the Kerala coast is June 1.\u00a0 The monsoon covers the entire country by July 15. Neither an early nor a late onset of the monsoon is unusual.<\/p>\n\n\n\n
Must read: Monsoon Forecast in India<\/a><\/strong><\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n

What are the IMD defined conditions for the onset of the monsoon?<\/h2>\n

According to the IMD, the onset of the monsoon happens when there is a significant transition in the large-scale atmospheric and ocean circulations in the Indo-Pacific region. The IMD essentially looks at the consistency of rainfall over a defined geography, the intensity of the rainfall, and the wind speed.<\/p>\n

Rainfall<\/strong>: The onset is declared if at least 60% of 14 designated meteorological stations in Kerala and Lakshadweep record at least 2.5 mm of rain for two consecutive days at any time after May 10.<\/p>\n

The onset over Kerala is declared on the second day, as long as specific wind and temperature criteria are also fulfilled.<\/p>\n

Wind field<\/strong>: The IMD says that the depth of westerlies should be up to 600 hectopascal (1 hPa is equal to 1 millibar of pressure) in the area that is bound by the equator to 10\u00baN latitude, and from longitude 55\u00baE to 80\u00baE.<\/p>\n

Heat<\/strong>: The INSAT-derived Outgoing Longwave Radiation (OLR) value should be below 200 watt per sq m (wm2) in the area between the 5\u00baN and 10\u00baN latitudes, and 70\u00baE and 75\u00baE longitudes.<\/p>\n

Note<\/strong>: Outgoing Longwave Radiation (OLR) value is a measure of the energy emitted to space by the Earth\u2019s surface, oceans, and atmosphere.<\/em><\/p>\n

What are the impacts of the delayed onset of the monsoon?<\/h2>\n

A delay in the onset over Kerala can potentially delay the arrival of the monsoon in other parts of the country, especially in the southern states. However, the delayed onset over Kerala does not automatically or invariably mean delays in the arrival of the monsoon over other parts of the country.<\/p>\n

This is because the northward progression of the monsoon after it has hit the Kerala coast is not uniform and depends on local factors, including the creation of low-pressure areas.<\/p>\n

A delay or an early arrival has no bearing on the quality or amount of rainfall, or its regional distribution across the country.<\/p>\n","protected":false},"excerpt":{"rendered":"

Source:\u00a0The post is based on the article\u00a0\u201cWhat is the \u2018onset\u2019 of the monsoon, and why the delayed onset is not necessarily bad news\u201d published in the Indian Express on\u00a09th June\u00a02023 What is the News? According to the India Meteorological Department (IMD), the southwest monsoon onset over Kerala this year will be delayed. What is meant… Continue reading What is the \u2018onset\u2019 of the monsoon, and why the delayed onset is not necessarily bad news<\/span><\/a><\/p>\n","protected":false},"author":10311,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"jetpack_post_was_ever_published":false,"footnotes":""},"categories":[1566,4182,11209,9],"tags":[10500],"class_list":["post-247239","post","type-post","status-publish","format-standard","hentry","category-daily-factly-articles","category-environment","category-geography-in-news","category-public","tag-indian-express","entry"],"jetpack_featured_media_url":"","views":"","jetpack_sharing_enabled":true,"_links":{"self":[{"href":"https:\/\/forumias.com\/blog\/wp-json\/wp\/v2\/posts\/247239","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/forumias.com\/blog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/forumias.com\/blog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/forumias.com\/blog\/wp-json\/wp\/v2\/users\/10311"}],"replies":[{"embeddable":true,"href":"https:\/\/forumias.com\/blog\/wp-json\/wp\/v2\/comments?post=247239"}],"version-history":[{"count":0,"href":"https:\/\/forumias.com\/blog\/wp-json\/wp\/v2\/posts\/247239\/revisions"}],"wp:attachment":[{"href":"https:\/\/forumias.com\/blog\/wp-json\/wp\/v2\/media?parent=247239"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/forumias.com\/blog\/wp-json\/wp\/v2\/categories?post=247239"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/forumias.com\/blog\/wp-json\/wp\/v2\/tags?post=247239"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}