{"id":60429,"date":"2026-07-17T10:12:29","date_gmt":"2026-07-17T08:12:29","guid":{"rendered":"https:\/\/alertes-meteo.com\/?page_id=60429"},"modified":"2026-07-17T10:12:29","modified_gmt":"2026-07-17T08:12:29","slug":"cartes-meteo-en-france-temperatures-point-de-rosee","status":"publish","type":"page","link":"https:\/\/alertes-meteo.com\/index.php\/cartes-meteo\/cartes-meteo-en-france-temperatures-point-de-rosee\/","title":{"rendered":"Cartes M\u00e9t\u00e9o en France &#8211; Temp\u00e9ratures point de ros\u00e9e"},"content":{"rendered":"<div class=\"fusion-fullwidth fullwidth-box fusion-builder-row-1 fusion-flex-container nonhundred-percent-fullwidth non-hundred-percent-height-scrolling\" style=\"--awb-border-radius-top-left:0px;--awb-border-radius-top-right:0px;--awb-border-radius-bottom-right:0px;--awb-border-radius-bottom-left:0px;--awb-flex-wrap:wrap;\" ><div class=\"fusion-builder-row fusion-row fusion-flex-align-items-flex-start fusion-flex-content-wrap\" style=\"max-width:1575px;margin-left: calc(-5% \/ 2 );margin-right: calc(-5% \/ 2 );\"><div class=\"fusion-layout-column fusion_builder_column fusion-builder-column-0 fusion_builder_column_1_1 1_1 fusion-flex-column\" style=\"--awb-bg-blend:overlay;--awb-bg-size:cover;--awb-width-large:100%;--awb-margin-top-large:0px;--awb-spacing-right-large:2.375%;--awb-margin-bottom-large:0px;--awb-spacing-left-large:2.375%;--awb-width-medium:100%;--awb-spacing-right-medium:2.375%;--awb-spacing-left-medium:2.375%;--awb-width-small:100%;--awb-spacing-right-small:2.375%;--awb-spacing-left-small:2.375%;\"><div class=\"fusion-column-wrapper fusion-flex-justify-content-flex-start fusion-content-layout-column\"><div class=\"fusion-text fusion-text-1\"><h1 align=\"center\"><b>Comment lire une carte d\u2019observation du point de ros\u00e9e ? (actualis\u00e9es en temps r\u00e9el)<\/b><\/h1>\n<\/div><div style=\"text-align:center;\">\n  <img class=\"lazyload\" decoding=\"async\" src=\"data:image\/gif;base64,R0lGODlhAQABAAAAACH5BAEKAAEALAAAAAABAAEAAAICTAEAOw==\" data-orig-src=\"https:\/\/www.meteociel.fr\/cartes_obs\/pointrosee.png\" \n       style=\"max-width:100%; height:auto;\" \n         alt=\"Carte des Temp\u00e9ratures Point de ros\u00e9e\">\n<\/div><script async src=\"https:\/\/pagead2.googlesyndication.com\/pagead\/js\/adsbygoogle.js?client=ca-pub-8902396130105212\"\n     crossorigin=\"anonymous\"><\/script>\n<!-- bas de page -->\n<ins class=\"adsbygoogle\"\n     style=\"display:block\"\n     data-ad-client=\"ca-pub-8902396130105212\"\n     data-ad-slot=\"7724440717\"\n     data-ad-format=\"auto\"\n     data-full-width-responsive=\"true\"><\/ins>\n<script>\n     (adsbygoogle = window.adsbygoogle || []).push({});\n<\/script><div class=\"fusion-text fusion-text-2\"><div class=\"has-inline-images my-2 first:mt-0 &#091;&amp;:has(&#091;data-inline-type=image&#093;)+&amp;:has(&#091;data-inline-type=image&#093;)_&#091;data-inline-type=image&#093;&#093;:hidden &#091;&amp;:has(table)_&#091;data-inline-type=image&#093;&#093;:hidden &#091;&amp;_h1:first-of-type&#093;:mt-8 &#091;&amp;_h2:first-of-type&#093;:mt-6\">\n<div>\n<div class=\"prose dark:prose-invert inline leading-relaxed break-words min-w-0 &#091;word-break:break-word&#093; &#091;&amp;_&gt;*:first-child&#093;:mt-0 &#091;&amp;_&gt;*:last-child&#093;:mb-0\" data-renderer=\"lm\">\n<h2 id=\"introduction\" class=\"font-editorial font-bold mb-2 mt-4 &#091;.has-inline-images_&amp;&#093;:clear-end text-lg first:mt-0 md:text-lg &#091;hr+&amp;&#093;:mt-4\">Introduction<\/h2>\n<\/div>\n<\/div>\n<\/div>\n<div class=\"has-inline-images my-2 first:mt-0 &#091;&amp;:has(&#091;data-inline-type=image&#093;)+&amp;:has(&#091;data-inline-type=image&#093;)_&#091;data-inline-type=image&#093;&#093;:hidden &#091;&amp;:has(table)_&#091;data-inline-type=image&#093;&#093;:hidden &#091;&amp;_h1:first-of-type&#093;:mt-8 &#091;&amp;_h2:first-of-type&#093;:mt-6\">\n<div>\n<div class=\"prose dark:prose-invert inline leading-relaxed break-words min-w-0 &#091;word-break:break-word&#093; &#091;&amp;_&gt;*:first-child&#093;:mt-0 &#091;&amp;_&gt;*:last-child&#093;:mb-0\" data-renderer=\"lm\">\n<p class=\"my-2 &#091;&amp;+p&#093;:mt-4 &#091;&amp;_strong:has(+br)&#093;:inline-block &#091;&amp;_strong:has(+br)&#093;:align-top\">Le point de ros\u00e9e, ou temp\u00e9rature de ros\u00e9e, est un indicateur cl\u00e9 pour comprendre l\u2019humidit\u00e9 de l\u2019air, la formation de brouillard, de nuages et le ressenti de chaleur en \u00e9t\u00e9. Les cartes d\u2019observation du point de ros\u00e9e en France permettent de visualiser en temps r\u00e9el la structure des masses d\u2019air humides ou s\u00e8ches et d\u2019anticiper certains ph\u00e9nom\u00e8nes comme les orages, les brumes matinales ou les nuits tropicales.<\/p>\n<\/div>\n<\/div>\n<\/div>\n<div class=\"has-inline-images my-2 first:mt-0 &#091;&amp;:has(&#091;data-inline-type=image&#093;)+&amp;:has(&#091;data-inline-type=image&#093;)_&#091;data-inline-type=image&#093;&#093;:hidden &#091;&amp;:has(table)_&#091;data-inline-type=image&#093;&#093;:hidden &#091;&amp;_h1:first-of-type&#093;:mt-8 &#091;&amp;_h2:first-of-type&#093;:mt-6\">\n<div>\n<div class=\"prose dark:prose-invert inline leading-relaxed break-words min-w-0 &#091;word-break:break-word&#093; &#091;&amp;_&gt;*:first-child&#093;:mt-0 &#091;&amp;_&gt;*:last-child&#093;:mb-0\" data-renderer=\"lm\">\n<h2 id=\"1-questce-que-le-point-de-rose-et-pourquoi-estil-i\" class=\"font-editorial font-bold mb-2 mt-4 &#091;.has-inline-images_&amp;&#093;:clear-end text-lg first:mt-0 md:text-lg &#091;hr+&amp;&#093;:mt-4\">1. Qu\u2019est\u2011ce que le point de ros\u00e9e et pourquoi est\u2011il important en m\u00e9t\u00e9o ?<\/h2>\n<\/div>\n<\/div>\n<\/div>\n<div class=\"has-inline-images my-2 first:mt-0 &#091;&amp;:has(&#091;data-inline-type=image&#093;)+&amp;:has(&#091;data-inline-type=image&#093;)_&#091;data-inline-type=image&#093;&#093;:hidden &#091;&amp;:has(table)_&#091;data-inline-type=image&#093;&#093;:hidden &#091;&amp;_h1:first-of-type&#093;:mt-8 &#091;&amp;_h2:first-of-type&#093;:mt-6\">\n<div>\n<div class=\"prose dark:prose-invert inline leading-relaxed break-words min-w-0 &#091;word-break:break-word&#093; &#091;&amp;_&gt;*:first-child&#093;:mt-0 &#091;&amp;_&gt;*:last-child&#093;:mb-0\" data-renderer=\"lm\">\n<p class=\"my-2 &#091;&amp;+p&#093;:mt-4 &#091;&amp;_strong:has(+br)&#093;:inline-block &#091;&amp;_strong:has(+br)&#093;:align-top\">Le point de ros\u00e9e est la temp\u00e9rature \u00e0 laquelle une masse d\u2019air doit se refroidir pour atteindre la saturation en vapeur d\u2019eau, c\u2019est\u2011\u00e0\u2011dire une humidit\u00e9 relative de 100\u202f%, ce qui correspond au \u00ab point de condensation \u00bb o\u00f9 se forment nuages, brouillard ou ros\u00e9e au sol. En dessous de cette temp\u00e9rature, la vapeur d\u2019eau se condense en gouttelettes sur les surfaces ou en suspension dans l\u2019air, expliquant la pr\u00e9sence de ros\u00e9e, de givre, de brume ou de bancs de brouillard selon les conditions. Le point de ros\u00e9e est donc un indicateur direct de la teneur en humidit\u00e9 de l\u2019air et compl\u00e8te la temp\u00e9rature et l\u2019humidit\u00e9 relative dans l\u2019analyse m\u00e9t\u00e9orologique et climatologique.<\/p>\n<\/div>\n<\/div>\n<\/div>\n<div class=\"has-inline-images my-2 first:mt-0 &#091;&amp;:has(&#091;data-inline-type=image&#093;)+&amp;:has(&#091;data-inline-type=image&#093;)_&#091;data-inline-type=image&#093;&#093;:hidden &#091;&amp;:has(table)_&#091;data-inline-type=image&#093;&#093;:hidden &#091;&amp;_h1:first-of-type&#093;:mt-8 &#091;&amp;_h2:first-of-type&#093;:mt-6\">\n<div>\n<div class=\"prose dark:prose-invert inline leading-relaxed break-words min-w-0 &#091;word-break:break-word&#093; &#091;&amp;_&gt;*:first-child&#093;:mt-0 &#091;&amp;_&gt;*:last-child&#093;:mb-0\" data-renderer=\"lm\">\n<h2 id=\"2-comment-lire-une-carte-dobservation-du-point-de\" class=\"font-editorial font-bold mb-2 mt-4 &#091;.has-inline-images_&amp;&#093;:clear-end text-lg first:mt-0 md:text-lg &#091;hr+&amp;&#093;:mt-4\">2. Comment lire une carte d\u2019observation du point de ros\u00e9e en France ?<\/h2>\n<\/div>\n<\/div>\n<\/div>\n<div class=\"has-inline-images my-2 first:mt-0 &#091;&amp;:has(&#091;data-inline-type=image&#093;)+&amp;:has(&#091;data-inline-type=image&#093;)_&#091;data-inline-type=image&#093;&#093;:hidden &#091;&amp;:has(table)_&#091;data-inline-type=image&#093;&#093;:hidden &#091;&amp;_h1:first-of-type&#093;:mt-8 &#091;&amp;_h2:first-of-type&#093;:mt-6\">\n<div>\n<div class=\"prose dark:prose-invert inline leading-relaxed break-words min-w-0 &#091;word-break:break-word&#093; &#091;&amp;_&gt;*:first-child&#093;:mt-0 &#091;&amp;_&gt;*:last-child&#093;:mb-0\" data-renderer=\"lm\">\n<p class=\"my-2 &#091;&amp;+p&#093;:mt-4 &#091;&amp;_strong:has(+br)&#093;:inline-block &#091;&amp;_strong:has(+br)&#093;:align-top\">Une carte d\u2019observation du point de ros\u00e9e affiche la temp\u00e9rature de ros\u00e9e mesur\u00e9e en temps r\u00e9el par les stations sur le territoire, souvent sous forme de valeurs ponctuelles ou de champs color\u00e9s en degr\u00e9s Celsius. Les valeurs \u00e9lev\u00e9es de point de ros\u00e9e traduisent un air tr\u00e8s humide avec une forte teneur en vapeur d\u2019eau, alors que les valeurs faibles indiquent un air sec et une moindre probabilit\u00e9 de condensation et de brouillard. Sur ces cartes, les contrastes spatiaux de point de ros\u00e9e permettent de rep\u00e9rer les fronti\u00e8res entre masses d\u2019air, les zones potentiellement orageuses ou au contraire plus stables, ainsi que les secteurs o\u00f9 les nuits risquent de rester tr\u00e8s douces.<\/p>\n<\/div>\n<\/div>\n<\/div>\n<div class=\"has-inline-images my-2 first:mt-0 &#091;&amp;:has(&#091;data-inline-type=image&#093;)+&amp;:has(&#091;data-inline-type=image&#093;)_&#091;data-inline-type=image&#093;&#093;:hidden &#091;&amp;:has(table)_&#091;data-inline-type=image&#093;&#093;:hidden &#091;&amp;_h1:first-of-type&#093;:mt-8 &#091;&amp;_h2:first-of-type&#093;:mt-6\">\n<div>\n<div class=\"prose dark:prose-invert inline leading-relaxed break-words min-w-0 &#091;word-break:break-word&#093; &#091;&amp;_&gt;*:first-child&#093;:mt-0 &#091;&amp;_&gt;*:last-child&#093;:mb-0\" data-renderer=\"lm\">\n<h2 id=\"3-o-trouver-des-cartes-du-point-de-rose-en-temps-r\" class=\"font-editorial font-bold mb-2 mt-4 &#091;.has-inline-images_&amp;&#093;:clear-end text-lg first:mt-0 md:text-lg &#091;hr+&amp;&#093;:mt-4\">3. O\u00f9 trouver des cartes du point de ros\u00e9e en temps r\u00e9el pour la France ?<\/h2>\n<\/div>\n<\/div>\n<\/div>\n<div class=\"has-inline-images my-2 first:mt-0 &#091;&amp;:has(&#091;data-inline-type=image&#093;)+&amp;:has(&#091;data-inline-type=image&#093;)_&#091;data-inline-type=image&#093;&#093;:hidden &#091;&amp;:has(table)_&#091;data-inline-type=image&#093;&#093;:hidden &#091;&amp;_h1:first-of-type&#093;:mt-8 &#091;&amp;_h2:first-of-type&#093;:mt-6\">\n<div>\n<div class=\"prose dark:prose-invert inline leading-relaxed break-words min-w-0 &#091;word-break:break-word&#093; &#091;&amp;_&gt;*:first-child&#093;:mt-0 &#091;&amp;_&gt;*:last-child&#093;:mb-0\" data-renderer=\"lm\">\n<p class=\"my-2 &#091;&amp;+p&#093;:mt-4 &#091;&amp;_strong:has(+br)&#093;:inline-block &#091;&amp;_strong:has(+br)&#093;:align-top\">Plusieurs sites proposent des cartes d\u2019observation du point de ros\u00e9e en temps r\u00e9el pour la France, notamment Meteociel, qui affiche les temp\u00e9ratures de ros\u00e9e des stations fran\u00e7aises et des pays limitrophes sous forme de carte de situation m\u00e9t\u00e9o en direct. Meteologix propose \u00e9galement une carte d\u2019observations du \u00ab dew point \u00bb pour la France, permettant de visualiser la temp\u00e9rature de ros\u00e9e \u00e0 un instant donn\u00e9 \u00e0 l\u2019\u00e9chelle du pays. Le site Infoclimat offre une carte interactive de point de ros\u00e9e bas\u00e9e sur les observations, tr\u00e8s utile pour analyser finement les masses d\u2019air et les fronts sur la France et les r\u00e9gions voisines.<\/p>\n<\/div>\n<\/div>\n<\/div>\n<div class=\"has-inline-images my-2 first:mt-0 &#091;&amp;:has(&#091;data-inline-type=image&#093;)+&amp;:has(&#091;data-inline-type=image&#093;)_&#091;data-inline-type=image&#093;&#093;:hidden &#091;&amp;:has(table)_&#091;data-inline-type=image&#093;&#093;:hidden &#091;&amp;_h1:first-of-type&#093;:mt-8 &#091;&amp;_h2:first-of-type&#093;:mt-6\">\n<div>\n<div class=\"prose dark:prose-invert inline leading-relaxed break-words min-w-0 &#091;word-break:break-word&#093; &#091;&amp;_&gt;*:first-child&#093;:mt-0 &#091;&amp;_&gt;*:last-child&#093;:mb-0\" data-renderer=\"lm\">\n<h2 id=\"4-quelle-est-la-diffrence-entre-temprature-de-lair\" class=\"font-editorial font-bold mb-2 mt-4 &#091;.has-inline-images_&amp;&#093;:clear-end text-lg first:mt-0 md:text-lg &#091;hr+&amp;&#093;:mt-4\">4. Quelle est la diff\u00e9rence entre temp\u00e9rature de l\u2019air, humidit\u00e9 relative et point de ros\u00e9e ?<\/h2>\n<\/div>\n<\/div>\n<\/div>\n<div class=\"has-inline-images my-2 first:mt-0 &#091;&amp;:has(&#091;data-inline-type=image&#093;)+&amp;:has(&#091;data-inline-type=image&#093;)_&#091;data-inline-type=image&#093;&#093;:hidden &#091;&amp;:has(table)_&#091;data-inline-type=image&#093;&#093;:hidden &#091;&amp;_h1:first-of-type&#093;:mt-8 &#091;&amp;_h2:first-of-type&#093;:mt-6\">\n<div>\n<div class=\"prose dark:prose-invert inline leading-relaxed break-words min-w-0 &#091;word-break:break-word&#093; &#091;&amp;_&gt;*:first-child&#093;:mt-0 &#091;&amp;_&gt;*:last-child&#093;:mb-0\" data-renderer=\"lm\">\n<p class=\"my-2 &#091;&amp;+p&#093;:mt-4 &#091;&amp;_strong:has(+br)&#093;:inline-block &#091;&amp;_strong:has(+br)&#093;:align-top\">La temp\u00e9rature de l\u2019air mesure le niveau de r\u00e9chauffement de la masse d\u2019air, tandis que l\u2019humidit\u00e9 relative exprime, en pourcentage, la quantit\u00e9 de vapeur d\u2019eau pr\u00e9sente par rapport \u00e0 la quantit\u00e9 maximale que l\u2019air pourrait contenir \u00e0 cette temp\u00e9rature. Le point de ros\u00e9e, lui, est une temp\u00e9rature li\u00e9e directement au contenu r\u00e9el en vapeur d\u2019eau de l\u2019air\u202f: plus le point de ros\u00e9e est \u00e9lev\u00e9, plus l\u2019air est charg\u00e9 en vapeur d\u2019eau, pour une temp\u00e9rature donn\u00e9e. Quand la temp\u00e9rature de l\u2019air descend jusqu\u2019au point de ros\u00e9e, l\u2019humidit\u00e9 relative atteint 100\u202f% et la condensation se produit, ce qui entra\u00eene la formation de ros\u00e9e, de brouillard ou de nuages selon le niveau o\u00f9 se produit la saturation.<\/p>\n<\/div>\n<\/div>\n<\/div>\n<div class=\"has-inline-images my-2 first:mt-0 &#091;&amp;:has(&#091;data-inline-type=image&#093;)+&amp;:has(&#091;data-inline-type=image&#093;)_&#091;data-inline-type=image&#093;&#093;:hidden &#091;&amp;:has(table)_&#091;data-inline-type=image&#093;&#093;:hidden &#091;&amp;_h1:first-of-type&#093;:mt-8 &#091;&amp;_h2:first-of-type&#093;:mt-6\">\n<div>\n<div class=\"prose dark:prose-invert inline leading-relaxed break-words min-w-0 &#091;word-break:break-word&#093; &#091;&amp;_&gt;*:first-child&#093;:mt-0 &#091;&amp;_&gt;*:last-child&#093;:mb-0\" data-renderer=\"lm\">\n<h2 id=\"5-comment-le-point-de-rose-influence-brouillard-nu\" class=\"font-editorial font-bold mb-2 mt-4 &#091;.has-inline-images_&amp;&#093;:clear-end text-lg first:mt-0 md:text-lg &#091;hr+&amp;&#093;:mt-4\">5. Comment le point de ros\u00e9e influence brouillard, nuages et orages ?<\/h2>\n<\/div>\n<\/div>\n<\/div>\n<div class=\"has-inline-images my-2 first:mt-0 &#091;&amp;:has(&#091;data-inline-type=image&#093;)+&amp;:has(&#091;data-inline-type=image&#093;)_&#091;data-inline-type=image&#093;&#093;:hidden &#091;&amp;:has(table)_&#091;data-inline-type=image&#093;&#093;:hidden &#091;&amp;_h1:first-of-type&#093;:mt-8 &#091;&amp;_h2:first-of-type&#093;:mt-6\">\n<div>\n<div class=\"prose dark:prose-invert inline leading-relaxed break-words min-w-0 &#091;word-break:break-word&#093; &#091;&amp;_&gt;*:first-child&#093;:mt-0 &#091;&amp;_&gt;*:last-child&#093;:mb-0\" data-renderer=\"lm\">\n<p class=\"my-2 &#091;&amp;+p&#093;:mt-4 &#091;&amp;_strong:has(+br)&#093;:inline-block &#091;&amp;_strong:has(+br)&#093;:align-top\">Lorsque la temp\u00e9rature de l\u2019air s\u2019abaisse jusqu\u2019au point de ros\u00e9e pr\u00e8s du sol, la masse d\u2019air atteint la saturation et de fines gouttelettes se forment, ce qui donne de la ros\u00e9e, du givre ou des bancs de brouillard selon la temp\u00e9rature et la saison. Si cette saturation se produit en altitude, la condensation de la vapeur d\u2019eau engendre la formation de nuages et peut conduire, en pr\u00e9sence d\u2019instabilit\u00e9, \u00e0 des nuages convectifs et \u00e0 des orages. En \u00e9t\u00e9, un point de ros\u00e9e \u00e9lev\u00e9 abaisse la hauteur de la base nuageuse dans une masse d\u2019air instable et renforce la capacit\u00e9 des ascendances \u00e0 se maintenir, ce qui augmente la probabilit\u00e9 de d\u00e9clenchement d\u2019orages diurnes.<\/p>\n<\/div>\n<\/div>\n<\/div>\n<div class=\"has-inline-images my-2 first:mt-0 &#091;&amp;:has(&#091;data-inline-type=image&#093;)+&amp;:has(&#091;data-inline-type=image&#093;)_&#091;data-inline-type=image&#093;&#093;:hidden &#091;&amp;:has(table)_&#091;data-inline-type=image&#093;&#093;:hidden &#091;&amp;_h1:first-of-type&#093;:mt-8 &#091;&amp;_h2:first-of-type&#093;:mt-6\">\n<div>\n<div class=\"prose dark:prose-invert inline leading-relaxed break-words min-w-0 &#091;word-break:break-word&#093; &#091;&amp;_&gt;*:first-child&#093;:mt-0 &#091;&amp;_&gt;*:last-child&#093;:mb-0\" data-renderer=\"lm\">\n<h2 id=\"6-pourquoi-les-fortes-valeurs-de-point-de-rose-ren\" class=\"font-editorial font-bold mb-2 mt-4 &#091;.has-inline-images_&amp;&#093;:clear-end text-lg first:mt-0 md:text-lg &#091;hr+&amp;&#093;:mt-4\">6. Pourquoi les fortes valeurs de point de ros\u00e9e rendent l\u2019air \u00ab lourd \u00bb et favorisent l\u2019inconfort en cas de chaleur ?<\/h2>\n<\/div>\n<\/div>\n<\/div>\n<div class=\"has-inline-images my-2 first:mt-0 &#091;&amp;:has(&#091;data-inline-type=image&#093;)+&amp;:has(&#091;data-inline-type=image&#093;)_&#091;data-inline-type=image&#093;&#093;:hidden &#091;&amp;:has(table)_&#091;data-inline-type=image&#093;&#093;:hidden &#091;&amp;_h1:first-of-type&#093;:mt-8 &#091;&amp;_h2:first-of-type&#093;:mt-6\">\n<div>\n<div class=\"prose dark:prose-invert inline leading-relaxed break-words min-w-0 &#091;word-break:break-word&#093; &#091;&amp;_&gt;*:first-child&#093;:mt-0 &#091;&amp;_&gt;*:last-child&#093;:mb-0\" data-renderer=\"lm\">\n<p class=\"my-2 &#091;&amp;+p&#093;:mt-4 &#091;&amp;_strong:has(+br)&#093;:inline-block &#091;&amp;_strong:has(+br)&#093;:align-top\">\u00c0 temp\u00e9rature de l\u2019air \u00e9gale, un point de ros\u00e9e \u00e9lev\u00e9 implique une humidit\u00e9 relative plus forte, ce qui r\u00e9duit la capacit\u00e9 de l\u2019air \u00e0 accepter la vapeur d\u2019eau issue de l\u2019\u00e9vaporation de la transpiration humaine. Cette limitation de l\u2019\u00e9vaporation rend le refroidissement du corps beaucoup moins efficace, expliquant pourquoi une journ\u00e9e \u00e0 28\u202f\u00b0C avec un point de ros\u00e9e de 20\u202f\u00b0C est ressentie comme nettement plus lourde et inconfortable qu\u2019une journ\u00e9e \u00e0 32\u202f\u00b0C avec un point de ros\u00e9e de 10\u202f\u00b0C. C\u2019est sur ce principe que reposent les indices de chaleur et de \u00ab temp\u00e9rature ressentie \u00bb, qui int\u00e8grent l\u2019humidit\u00e9 dans l\u2019estimation du niveau de stress thermique en situation de canicule.<\/p>\n<\/div>\n<\/div>\n<\/div>\n<div class=\"has-inline-images my-2 first:mt-0 &#091;&amp;:has(&#091;data-inline-type=image&#093;)+&amp;:has(&#091;data-inline-type=image&#093;)_&#091;data-inline-type=image&#093;&#093;:hidden &#091;&amp;:has(table)_&#091;data-inline-type=image&#093;&#093;:hidden &#091;&amp;_h1:first-of-type&#093;:mt-8 &#091;&amp;_h2:first-of-type&#093;:mt-6\">\n<div>\n<div class=\"prose dark:prose-invert inline leading-relaxed break-words min-w-0 &#091;word-break:break-word&#093; &#091;&amp;_&gt;*:first-child&#093;:mt-0 &#091;&amp;_&gt;*:last-child&#093;:mb-0\" data-renderer=\"lm\">\n<h2 id=\"7-comment-est-calcul-le-point-de-rose-sur-les-cart\" class=\"font-editorial font-bold mb-2 mt-4 &#091;.has-inline-images_&amp;&#093;:clear-end text-lg first:mt-0 md:text-lg &#091;hr+&amp;&#093;:mt-4\">7. Comment est calcul\u00e9 le point de ros\u00e9e sur les cartes m\u00e9t\u00e9o ?<\/h2>\n<\/div>\n<\/div>\n<\/div>\n<div class=\"has-inline-images my-2 first:mt-0 &#091;&amp;:has(&#091;data-inline-type=image&#093;)+&amp;:has(&#091;data-inline-type=image&#093;)_&#091;data-inline-type=image&#093;&#093;:hidden &#091;&amp;:has(table)_&#091;data-inline-type=image&#093;&#093;:hidden &#091;&amp;_h1:first-of-type&#093;:mt-8 &#091;&amp;_h2:first-of-type&#093;:mt-6\">\n<div>\n<div class=\"prose dark:prose-invert inline leading-relaxed break-words min-w-0 &#091;word-break:break-word&#093; &#091;&amp;_&gt;*:first-child&#093;:mt-0 &#091;&amp;_&gt;*:last-child&#093;:mb-0\" data-renderer=\"lm\">\n<p class=\"my-2 &#091;&amp;+p&#093;:mt-4 &#091;&amp;_strong:has(+br)&#093;:inline-block &#091;&amp;_strong:has(+br)&#093;:align-top\">Le point de ros\u00e9e peut \u00eatre calcul\u00e9 par des instruments d\u00e9di\u00e9s comme les hygrom\u00e8tres \u00e0 miroir de point de ros\u00e9e ou des stations m\u00e9t\u00e9o num\u00e9riques qui combinent temp\u00e9rature, pression atmosph\u00e9rique et humidit\u00e9 relative pour en d\u00e9duire sa valeur. En m\u00e9t\u00e9orologie et en mod\u00e9lisation num\u00e9rique, on utilise couramment des relations thermodynamiques comme la formule de Magnus, qui relie la temp\u00e9rature, la pression de vapeur satur\u00e9e et la temp\u00e9rature de ros\u00e9e via des constantes pour les r\u00e9gimes au\u2011dessus et au\u2011dessous de 0\u202f\u00b0C. Les cartes d\u2019observation ou de pr\u00e9vision du point de ros\u00e9e affichent ainsi des valeurs calcul\u00e9es \u00e0 partir des donn\u00e9es brutes de station ou de mod\u00e8le, ce qui permet de suivre les champs d\u2019humidit\u00e9 avec une bonne pr\u00e9cision spatiale.<\/p>\n<\/div>\n<\/div>\n<\/div>\n<div class=\"has-inline-images my-2 first:mt-0 &#091;&amp;:has(&#091;data-inline-type=image&#093;)+&amp;:has(&#091;data-inline-type=image&#093;)_&#091;data-inline-type=image&#093;&#093;:hidden &#091;&amp;:has(table)_&#091;data-inline-type=image&#093;&#093;:hidden &#091;&amp;_h1:first-of-type&#093;:mt-8 &#091;&amp;_h2:first-of-type&#093;:mt-6\">\n<div>\n<div class=\"prose dark:prose-invert inline leading-relaxed break-words min-w-0 &#091;word-break:break-word&#093; &#091;&amp;_&gt;*:first-child&#093;:mt-0 &#091;&amp;_&gt;*:last-child&#093;:mb-0\" data-renderer=\"lm\">\n<h2 id=\"8--quelle-chelle-sont-ralises-les-cartes-de-point\" class=\"font-editorial font-bold mb-2 mt-4 &#091;.has-inline-images_&amp;&#093;:clear-end text-lg first:mt-0 md:text-lg &#091;hr+&amp;&#093;:mt-4\">8. \u00c0 quelle \u00e9chelle sont r\u00e9alis\u00e9es les cartes de point de ros\u00e9e (stations, mod\u00e8les, mailles fines) ?<\/h2>\n<\/div>\n<\/div>\n<\/div>\n<div class=\"has-inline-images my-2 first:mt-0 &#091;&amp;:has(&#091;data-inline-type=image&#093;)+&amp;:has(&#091;data-inline-type=image&#093;)_&#091;data-inline-type=image&#093;&#093;:hidden &#091;&amp;:has(table)_&#091;data-inline-type=image&#093;&#093;:hidden &#091;&amp;_h1:first-of-type&#093;:mt-8 &#091;&amp;_h2:first-of-type&#093;:mt-6\">\n<div>\n<div class=\"prose dark:prose-invert inline leading-relaxed break-words min-w-0 &#091;word-break:break-word&#093; &#091;&amp;_&gt;*:first-child&#093;:mt-0 &#091;&amp;_&gt;*:last-child&#093;:mb-0\" data-renderer=\"lm\">\n<p class=\"my-2 &#091;&amp;+p&#093;:mt-4 &#091;&amp;_strong:has(+br)&#093;:inline-block &#091;&amp;_strong:has(+br)&#093;:align-top\">Les cartes d\u2019observation du point de ros\u00e9e pour la France se basent g\u00e9n\u00e9ralement sur les r\u00e9seaux de stations, qu\u2019elles soient officielles ou issues de r\u00e9seaux collaboratifs, et repr\u00e9sentent les valeurs de ros\u00e9e sous forme de points ou de champs interpol\u00e9s. Les mod\u00e8les num\u00e9riques, comme ceux pr\u00e9sent\u00e9s sur des plateformes de cartes de pr\u00e9vision europ\u00e9ennes, proposent des champs de point de ros\u00e9e maill\u00e9s \u00e0 r\u00e9solution kilom\u00e9trique, mis \u00e0 jour plusieurs fois par jour pour suivre l\u2019\u00e9volution de l\u2019humidit\u00e9 sur plusieurs jours. Cette combinaison d\u2019observations en temps r\u00e9el et de mailles de mod\u00e8les permet aux m\u00e9t\u00e9orologues et aux passionn\u00e9s de visualiser l\u2019humidit\u00e9 de la masse d\u2019air \u00e0 diff\u00e9rentes \u00e9chelles, du local au synoptique.<\/p>\n<\/div>\n<\/div>\n<\/div>\n<div class=\"has-inline-images my-2 first:mt-0 &#091;&amp;:has(&#091;data-inline-type=image&#093;)+&amp;:has(&#091;data-inline-type=image&#093;)_&#091;data-inline-type=image&#093;&#093;:hidden &#091;&amp;:has(table)_&#091;data-inline-type=image&#093;&#093;:hidden &#091;&amp;_h1:first-of-type&#093;:mt-8 &#091;&amp;_h2:first-of-type&#093;:mt-6\">\n<div>\n<div class=\"prose dark:prose-invert inline leading-relaxed break-words min-w-0 &#091;word-break:break-word&#093; &#091;&amp;_&gt;*:first-child&#093;:mt-0 &#091;&amp;_&gt;*:last-child&#093;:mb-0\" data-renderer=\"lm\">\n<h2 id=\"9-comment-utiliser-les-cartes-de-point-de-rose-pou\" class=\"font-editorial font-bold mb-2 mt-4 &#091;.has-inline-images_&amp;&#093;:clear-end text-lg first:mt-0 md:text-lg &#091;hr+&amp;&#093;:mt-4\">9. Comment utiliser les cartes de point de ros\u00e9e pour l\u2019agriculture et la gestion des risques ?<\/h2>\n<\/div>\n<\/div>\n<\/div>\n<div class=\"has-inline-images my-2 first:mt-0 &#091;&amp;:has(&#091;data-inline-type=image&#093;)+&amp;:has(&#091;data-inline-type=image&#093;)_&#091;data-inline-type=image&#093;&#093;:hidden &#091;&amp;:has(table)_&#091;data-inline-type=image&#093;&#093;:hidden &#091;&amp;_h1:first-of-type&#093;:mt-8 &#091;&amp;_h2:first-of-type&#093;:mt-6\">\n<div>\n<div class=\"prose dark:prose-invert inline leading-relaxed break-words min-w-0 &#091;word-break:break-word&#093; &#091;&amp;_&gt;*:first-child&#093;:mt-0 &#091;&amp;_&gt;*:last-child&#093;:mb-0\" data-renderer=\"lm\">\n<p class=\"my-2 &#091;&amp;+p&#093;:mt-4 &#091;&amp;_strong:has(+br)&#093;:inline-block &#091;&amp;_strong:has(+br)&#093;:align-top\">En agriculture, des points de ros\u00e9e \u00e9lev\u00e9s en fin de nuit par ciel d\u00e9gag\u00e9 et vent faible traduisent une forte probabilit\u00e9 de ros\u00e9e ou de brouillard, ce qui peut apporter une humidit\u00e9 bienvenue aux cultures en fin d\u2019\u00e9t\u00e9 ou en d\u00e9but d\u2019automne. \u00c0 l\u2019inverse, des points de ros\u00e9e tr\u00e8s bas indiquent un air sec et un risque plus \u00e9lev\u00e9 de dess\u00e8chement, ce qui peut n\u00e9cessiter un ajustement des pratiques d\u2019irrigation ou de protection des sols. Les cartes de point de ros\u00e9e, en lien avec la temp\u00e9rature et le vent, aident aussi \u00e0 anticiper les nuits chaudes, la persistance de conditions caniculaires ou la probabilit\u00e9 d\u2019orages, des param\u00e8tres importants pour la gestion des risques agricoles et environnementaux.<\/p>\n<\/div>\n<\/div>\n<\/div>\n<div class=\"has-inline-images my-2 first:mt-0 &#091;&amp;:has(&#091;data-inline-type=image&#093;)+&amp;:has(&#091;data-inline-type=image&#093;)_&#091;data-inline-type=image&#093;&#093;:hidden &#091;&amp;:has(table)_&#091;data-inline-type=image&#093;&#093;:hidden &#091;&amp;_h1:first-of-type&#093;:mt-8 &#091;&amp;_h2:first-of-type&#093;:mt-6\">\n<div>\n<div class=\"prose dark:prose-invert inline leading-relaxed break-words min-w-0 &#091;word-break:break-word&#093; &#091;&amp;_&gt;*:first-child&#093;:mt-0 &#091;&amp;_&gt;*:last-child&#093;:mb-0\" data-renderer=\"lm\">\n<h2 id=\"10-peuton-consulter-lhistorique-du-point-de-rose-e\" class=\"font-editorial font-bold mb-2 mt-4 &#091;.has-inline-images_&amp;&#093;:clear-end text-lg first:mt-0 md:text-lg &#091;hr+&amp;&#093;:mt-4\">10. Peut\u2011on consulter l\u2019historique du point de ros\u00e9e et r\u00e9aliser des \u00e9tudes climatologiques en France ?<\/h2>\n<\/div>\n<\/div>\n<\/div>\n<div class=\"has-inline-images my-2 first:mt-0 &#091;&amp;:has(&#091;data-inline-type=image&#093;)+&amp;:has(&#091;data-inline-type=image&#093;)_&#091;data-inline-type=image&#093;&#093;:hidden &#091;&amp;:has(table)_&#091;data-inline-type=image&#093;&#093;:hidden &#091;&amp;_h1:first-of-type&#093;:mt-8 &#091;&amp;_h2:first-of-type&#093;:mt-6\">\n<div>\n<div class=\"prose dark:prose-invert inline leading-relaxed break-words min-w-0 &#091;word-break:break-word&#093; &#091;&amp;_&gt;*:first-child&#093;:mt-0 &#091;&amp;_&gt;*:last-child&#093;:mb-0\" data-renderer=\"lm\">\n<p class=\"my-2 &#091;&amp;+p&#093;:mt-4 &#091;&amp;_strong:has(+br)&#093;:inline-block &#091;&amp;_strong:has(+br)&#093;:align-top\">L\u2019historique du point de ros\u00e9e est disponible via des fichiers d\u2019observations et des bases de donn\u00e9es m\u00e9t\u00e9o publiques ou sp\u00e9cialis\u00e9es, permettant d\u2019analyser l\u2019\u00e9volution de la teneur en vapeur d\u2019eau et des \u00e9pisodes de nuits tropicales sur plusieurs ann\u00e9es. Ces donn\u00e9es d\u2019observation, combin\u00e9es aux r\u00e9analyses issues des mod\u00e8les num\u00e9riques, offrent la possibilit\u00e9 de mener des \u00e9tudes climatologiques sur la fr\u00e9quence des conditions tr\u00e8s humides, des brouillards, des canicules ou des orages \u00e0 partir du comportement du point de ros\u00e9e. Pour un travail \u00e9ditorial ou scientifique, il est conseill\u00e9 de s\u2019appuyer sur ces s\u00e9ries longues de point de ros\u00e9e et d\u2019autres variables d\u2019humidit\u00e9 afin de documenter les impacts du changement climatique sur le ressenti et les ph\u00e9nom\u00e8nes extr\u00eames en France.<\/p>\n<\/div>\n<\/div>\n<\/div>\n<\/div><\/div><\/div><\/div><\/div>\n","protected":false},"excerpt":{"rendered":"","protected":false},"author":1,"featured_media":0,"parent":14485,"menu_order":0,"comment_status":"closed","ping_status":"closed","template":"","meta":{"_seopress_titles_title":"Comment lire une carte d\u2019observation du point de ros\u00e9e ?","_seopress_titles_desc":"Cartes M\u00e9t\u00e9o en France - Temp\u00e9ratures point de ros\u00e9e en Direct","_seopress_robots_index":"","_seopress_robots_follow":"","_seopress_robots_imageindex":"","_seopress_robots_snippet":"","_seopress_robots_primary_cat":"","_seopress_robots_breadcrumbs":"","_seopress_robots_freeze_modified_date":"","_seopress_robots_custom_modified_date":"","_seopress_robots_canonical":"","_seopress_social_fb_title":"","_seopress_social_fb_desc":"","_seopress_social_fb_img":"","_seopress_social_fb_img_attachment_id":0,"_seopress_social_fb_img_width":0,"_seopress_social_fb_img_height":0,"_seopress_social_twitter_title":"","_seopress_social_twitter_desc":"","_seopress_social_twitter_img":"","_seopress_social_twitter_img_attachment_id":0,"_seopress_social_twitter_img_width":0,"_seopress_social_twitter_img_height":0,"_seopress_redirections_value":"","_seopress_redirections_enabled":"","_seopress_redirections_enabled_regex":"","_seopress_redirections_logged_status":"both","_seopress_redirections_param":"","_seopress_redirections_type":301,"_seopress_analysis_target_kw":"temperature mer","footnotes":""},"class_list":["post-60429","page","type-page","status-publish","hentry"],"_links":{"self":[{"href":"https:\/\/alertes-meteo.com\/index.php\/wp-json\/wp\/v2\/pages\/60429","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/alertes-meteo.com\/index.php\/wp-json\/wp\/v2\/pages"}],"about":[{"href":"https:\/\/alertes-meteo.com\/index.php\/wp-json\/wp\/v2\/types\/page"}],"author":[{"embeddable":true,"href":"https:\/\/alertes-meteo.com\/index.php\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/alertes-meteo.com\/index.php\/wp-json\/wp\/v2\/comments?post=60429"}],"version-history":[{"count":1,"href":"https:\/\/alertes-meteo.com\/index.php\/wp-json\/wp\/v2\/pages\/60429\/revisions"}],"predecessor-version":[{"id":60430,"href":"https:\/\/alertes-meteo.com\/index.php\/wp-json\/wp\/v2\/pages\/60429\/revisions\/60430"}],"up":[{"embeddable":true,"href":"https:\/\/alertes-meteo.com\/index.php\/wp-json\/wp\/v2\/pages\/14485"}],"wp:attachment":[{"href":"https:\/\/alertes-meteo.com\/index.php\/wp-json\/wp\/v2\/media?parent=60429"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}