{"id":1953,"date":"2025-08-18T10:47:21","date_gmt":"2025-08-18T08:47:21","guid":{"rendered":"https:\/\/acriv.org\/WP\/?page_id=1953"},"modified":"2025-08-18T11:06:35","modified_gmt":"2025-08-18T09:06:35","slug":"%e2%9b%88%ef%b8%8fmto-les-fronts","status":"publish","type":"page","link":"https:\/\/acriv.org\/WP\/%e2%9b%88%ef%b8%8fmto-les-fronts\/","title":{"rendered":"\u26c8\ufe0fMTO : LES FRONTS"},"content":{"rendered":"\n<figure class=\"wp-block-image size-full is-resized\"><img loading=\"lazy\" decoding=\"async\" width=\"800\" height=\"244\" src=\"https:\/\/acriv.org\/WP\/wp-content\/uploads\/2025\/08\/coupe-fronts.png\" alt=\"\" class=\"wp-image-1955\" style=\"width:863px;height:auto\" srcset=\"https:\/\/acriv.org\/WP\/wp-content\/uploads\/2025\/08\/coupe-fronts.png 800w, https:\/\/acriv.org\/WP\/wp-content\/uploads\/2025\/08\/coupe-fronts-300x92.png 300w, https:\/\/acriv.org\/WP\/wp-content\/uploads\/2025\/08\/coupe-fronts-768x234.png 768w, https:\/\/acriv.org\/WP\/wp-content\/uploads\/2025\/08\/coupe-fronts-650x198.png 650w, https:\/\/acriv.org\/WP\/wp-content\/uploads\/2025\/08\/coupe-fronts-310x95.png 310w, https:\/\/acriv.org\/WP\/wp-content\/uploads\/2025\/08\/coupe-fronts-150x46.png 150w\" sizes=\"auto, (max-width: 800px) 100vw, 800px\" \/><\/figure>\n\n\n\n<p>Les <strong>fronts m\u00e9t\u00e9orologiques<\/strong> sont des <strong>zones de transition<\/strong> entre deux masses d\u2019air aux caract\u00e9ristiques diff\u00e9rentes (temp\u00e9rature, humidit\u00e9, densit\u00e9). Leur dynamique explique une grande partie des ph\u00e9nom\u00e8nes m\u00e9t\u00e9o (pluie, orages, neige).<\/p>\n\n\n<div class=\"wp-block-image\">\n<figure class=\"aligncenter size-full is-resized\"><img loading=\"lazy\" decoding=\"async\" width=\"254\" height=\"210\" src=\"https:\/\/acriv.org\/WP\/wp-content\/uploads\/2025\/08\/FrontSchema.png\" alt=\"\" class=\"wp-image-1954\" style=\"width:282px;height:auto\" srcset=\"https:\/\/acriv.org\/WP\/wp-content\/uploads\/2025\/08\/FrontSchema.png 254w, https:\/\/acriv.org\/WP\/wp-content\/uploads\/2025\/08\/FrontSchema-127x105.png 127w\" sizes=\"auto, (max-width: 254px) 100vw, 254px\" \/><\/figure>\n<\/div>\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n\n\n<h1 class=\"wp-block-heading\">\ud83c\udf21\ufe0f 1. Le front chaud<\/h1>\n\n\n\n<ul class=\"wp-block-list\">\n<li><strong>Situation :<\/strong> l\u2019air chaud avance sur de l\u2019air froid, plus dense, qui reste plaqu\u00e9 au sol.<\/li>\n\n\n\n<li>L\u2019air chaud glisse progressivement <em>au-dessus<\/em> de l\u2019air froid \u2192 mont\u00e9e douce et \u00e9tendue.<\/li>\n\n\n\n<li><strong>Nuages associ\u00e9s :<\/strong> succession de <strong>cirrus \u2192 cirrostratus \u2192 altostratus \u2192 nimbostratus<\/strong>.<\/li>\n\n\n\n<li><strong>Cons\u00e9quences m\u00e9t\u00e9o :<\/strong>\n<ul class=\"wp-block-list\">\n<li>ciel qui se voile progressivement,<\/li>\n\n\n\n<li>pluie\/neige <strong>continue et durable<\/strong>, souvent faible \u00e0 mod\u00e9r\u00e9e,<\/li>\n\n\n\n<li>am\u00e9lioration apr\u00e8s le passage, avec retour de l\u2019air chaud.<\/li>\n<\/ul>\n<\/li>\n<\/ul>\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n\n\n<h1 class=\"wp-block-heading\">\u2744\ufe0f 2. Le front froid<\/h1>\n\n\n\n<ul class=\"wp-block-list\">\n<li><strong>Situation :<\/strong> l\u2019air froid avance et <strong>soul\u00e8ve brutalement<\/strong> l\u2019air chaud, qui est plus l\u00e9ger.<\/li>\n\n\n\n<li>Ascendance rapide \u2192 condensation violente.<\/li>\n\n\n\n<li><strong>Nuages associ\u00e9s :<\/strong> <strong>cumulus \u2192 cumulonimbus<\/strong>, souvent \u00e0 d\u00e9veloppement vertical.<\/li>\n\n\n\n<li><strong>Cons\u00e9quences m\u00e9t\u00e9o :<\/strong>\n<ul class=\"wp-block-list\">\n<li>averses soudaines et intenses,<\/li>\n\n\n\n<li>orages, gr\u00eale, rafales de vent,<\/li>\n\n\n\n<li>baisse nette de la temp\u00e9rature apr\u00e8s le passage.<\/li>\n<\/ul>\n<\/li>\n<\/ul>\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n\n\n<h1 class=\"wp-block-heading\">\ud83c\udf2a\ufe0f 3. Le front occlus (ou occlusion)<\/h1>\n\n\n\n<ul class=\"wp-block-list\">\n<li><strong>Situation :<\/strong> un front froid rattrape un front chaud.<\/li>\n\n\n\n<li>L\u2019air chaud, coinc\u00e9 entre deux masses d\u2019air froid, est forc\u00e9 de s\u2019\u00e9lever totalement.<\/li>\n\n\n\n<li><strong>Nuages associ\u00e9s :<\/strong> m\u00e9lange des deux types \u2192 stratus, nimbostratus, cumulonimbus.<\/li>\n\n\n\n<li><strong>Cons\u00e9quences m\u00e9t\u00e9o :<\/strong>\n<ul class=\"wp-block-list\">\n<li>temps perturb\u00e9 et complexe,<\/li>\n\n\n\n<li>pluies\/neiges durables et parfois fortes,<\/li>\n\n\n\n<li>souvent associ\u00e9 aux <strong>d\u00e9pressions matures<\/strong>.<\/li>\n<\/ul>\n<\/li>\n<\/ul>\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n\n\n<h1 class=\"wp-block-heading\">\ud83c\udf2b\ufe0f 4. Le front stationnaire<\/h1>\n\n\n\n<ul class=\"wp-block-list\">\n<li><strong>Situation :<\/strong> deux masses d\u2019air (chaud et froid) s\u2019affrontent mais <strong>aucune ne progresse vraiment<\/strong>.<\/li>\n\n\n\n<li>La limite reste bloqu\u00e9e sur place pendant des heures\/jours.<\/li>\n\n\n\n<li><strong>Nuages associ\u00e9s :<\/strong> altostratus, nimbostratus.<\/li>\n\n\n\n<li><strong>Cons\u00e9quences m\u00e9t\u00e9o :<\/strong>\n<ul class=\"wp-block-list\">\n<li>pr\u00e9cipitations continues sur de longues dur\u00e9es,<\/li>\n\n\n\n<li>risque d\u2019inondations si persistant.<\/li>\n<\/ul>\n<\/li>\n<\/ul>\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n\n<div class=\"wp-block-image\">\n<figure class=\"aligncenter size-full is-resized\"><img loading=\"lazy\" decoding=\"async\" width=\"282\" height=\"103\" src=\"https:\/\/acriv.org\/WP\/wp-content\/uploads\/2025\/08\/fig_symboles_fronts.gif\" alt=\"\" class=\"wp-image-1965\" style=\"width:324px;height:auto\"\/><\/figure>\n<\/div>\n\n\n<h2 class=\"wp-block-heading\">\ud83d\udd0e R\u00e9sum\u00e9 visuel (simplifi\u00e9)<\/h2>\n\n\n\n<ul class=\"wp-block-list\">\n<li><strong>Front chaud<\/strong> : air chaud monte doucement \u2192 pluie longue et r\u00e9guli\u00e8re.<\/li>\n\n\n\n<li><strong>Front froid<\/strong> : air chaud repouss\u00e9 brutalement \u2192 orages, averses violentes.<\/li>\n\n\n\n<li><strong>Front occlus<\/strong> : air chaud pi\u00e9g\u00e9 et soulev\u00e9 \u2192 mauvais temps durable.<\/li>\n\n\n\n<li><strong>Front stationnaire<\/strong> : masses d\u2019air bloqu\u00e9es \u2192 pluies persistantes.<\/li>\n<\/ul>\n","protected":false},"excerpt":{"rendered":"<p>Les fronts m\u00e9t\u00e9orologiques sont des zones de transition entre deux masses d\u2019air aux caract\u00e9ristiques diff\u00e9rentes (temp\u00e9rature, humidit\u00e9, densit\u00e9). Leur dynamique explique une grande partie des ph\u00e9nom\u00e8nes m\u00e9t\u00e9o (pluie, orages, neige). \ud83c\udf21\ufe0f 1. Le front chaud \u2744\ufe0f 2. Le front froid \ud83c\udf2a\ufe0f 3. Le front occlus (ou occlusion) \ud83c\udf2b\ufe0f 4. Le front stationnaire \ud83d\udd0e R\u00e9sum\u00e9 visuel (simplifi\u00e9)<\/p>\n","protected":false},"author":1,"featured_media":0,"parent":0,"menu_order":0,"comment_status":"closed","ping_status":"closed","template":"","meta":{"footnotes":""},"class_list":["post-1953","page","type-page","status-publish","hentry"],"jetpack_sharing_enabled":true,"_links":{"self":[{"href":"https:\/\/acriv.org\/WP\/wp-json\/wp\/v2\/pages\/1953","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/acriv.org\/WP\/wp-json\/wp\/v2\/pages"}],"about":[{"href":"https:\/\/acriv.org\/WP\/wp-json\/wp\/v2\/types\/page"}],"author":[{"embeddable":true,"href":"https:\/\/acriv.org\/WP\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/acriv.org\/WP\/wp-json\/wp\/v2\/comments?post=1953"}],"version-history":[{"count":3,"href":"https:\/\/acriv.org\/WP\/wp-json\/wp\/v2\/pages\/1953\/revisions"}],"predecessor-version":[{"id":1986,"href":"https:\/\/acriv.org\/WP\/wp-json\/wp\/v2\/pages\/1953\/revisions\/1986"}],"wp:attachment":[{"href":"https:\/\/acriv.org\/WP\/wp-json\/wp\/v2\/media?parent=1953"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}