{"id":105,"date":"2017-09-28T15:33:31","date_gmt":"2017-09-28T18:33:31","guid":{"rendered":"http:\/\/scidev\/wordpress\/?page_id=105"},"modified":"2025-07-09T10:45:42","modified_gmt":"2025-07-09T14:45:42","slug":"weather","status":"publish","type":"page","link":"https:\/\/www.apex-telescope.org\/ns\/observing\/weather\/","title":{"rendered":"Weather"},"content":{"rendered":"\n<p>The precipitable water vapour (PWV) is  the crucial parameter that determines the atmospheric transparency for sub-millimetre observations. At the APEX site on Llano de Chajnantor the amount of PWV is typically 1.0 mm and falls below 0.5 mm up to 25% of the time.<\/p>\n\n\n\n<hr class=\"wp-block-separator has-css-opacity is-style-wide\"\/>\n\n\n\n<div class=\"wp-block-ugb-feature ugb-feature ugb-734e1aa ugb-feature--v2 ugb-feature--design-plain ugb-feature--invert ugb-main-block\"><style>.ugb-734e1aa .ugb-button{border-radius:4px !important}.ugb-734e1aa .ugb-button:before{border-radius:4px !important}.ugb-734e1aa .ugb-inner-block{text-align:left}@media screen and (min-width:768px){.ugb-734e1aa .ugb-img{width:80px;height:auto !important}}<\/style><div class=\"ugb-inner-block\"><div class=\"ugb-block-content\"><div class=\"ugb-feature__item\"><div class=\"ugb-feature__content\"><h2 class=\"ugb-feature__title\">Weather data <\/h2><p class=\"ugb-feature__description\">Check here the current weather conditions at the APEX site in Chajnantor: PWV, temperature, humidity, pressure, wind speed. Access also historical data&#8230;<\/p><div class=\"ugb-button-container\"><a class=\"ugb-button ugb-button--size-normal ugb-button--design-ghost\" href=\"http:\/\/www.apex-telescope.org\/ns\/weather\/weather-data\/\" rel=\"\" title=\"\"><span class=\"ugb-button--inner\">Go<\/span><\/a><\/div><\/div><div class=\"ugb-feature__image-side\"><img decoding=\"async\" class=\"ugb-feature__image ugb-img wp-image-1723 ugb-image--shape-stretch\" src=\"http:\/\/www.apex-telescope.org\/ns\/wp-content\/uploads\/2019\/03\/Meteo-Station-e1552611046566.png\" alt=\"\" title=\"\" height=\"76\"\/><\/div><\/div><\/div><\/div><\/div>\n\n\n\n<hr class=\"wp-block-separator has-css-opacity is-style-wide\"\/>\n\n\n\n<div class=\"wp-block-ugb-feature ugb-feature ugb-a915322 ugb-feature--v2 ugb-feature--design-plain ugb-main-block\"><style>.ugb-a915322 .ugb-button{border-radius:4px !important}.ugb-a915322 .ugb-button:before{border-radius:4px !important}.ugb-a915322 .ugb-inner-block{text-align:left}@media screen and (min-width:768px){.ugb-a915322 .ugb-img{width:300px;height:auto !important}}<\/style><div class=\"ugb-inner-block\"><div class=\"ugb-block-content\"><div class=\"ugb-feature__item\"><div class=\"ugb-feature__content\"><h2 class=\"ugb-feature__title\">Atmospheric transmission <\/h2><p class=\"ugb-feature__description\">To prepare the observations and make time estimates for different atmospheric conditions check our <a href=\"https:\/\/www.apex-telescope.org\/ns\/observing-run\/observing\/instrument-setup-tool\/\">instrument setup tool<\/a>, based on the\u00a0ATM model\u00a0. <br>You can find here an interface to check only the atmospheric transmission without the instrumental layouts.<\/p><div class=\"ugb-button-container\"><a class=\"ugb-button ugb-button--size-normal ugb-button--design-ghost\" href=\"http:\/\/www.apex-telescope.org\/sites\/chajnantor\/atmosphere\/transpwv\/index_ns.php\" target=\"_blank\" rel=\"noopener noreferrer\" title=\"\"><span class=\"ugb-button--inner\">Go<\/span><\/a><\/div><\/div><div class=\"ugb-feature__image-side\"><img decoding=\"async\" class=\"ugb-feature__image ugb-img wp-image-1724 ugb-image--shape-stretch\" src=\"http:\/\/www.apex-telescope.org\/ns\/wp-content\/uploads\/2019\/03\/atm_other-300x221.png\" alt=\"\" title=\"\" height=\"221\" srcset=\"https:\/\/www.apex-telescope.org\/ns\/wp-content\/uploads\/2019\/03\/atm_other-300x221.png 300w, https:\/\/www.apex-telescope.org\/ns\/wp-content\/uploads\/2019\/03\/atm_other-768x566.png 768w, https:\/\/www.apex-telescope.org\/ns\/wp-content\/uploads\/2019\/03\/atm_other-360x266.png 360w, https:\/\/www.apex-telescope.org\/ns\/wp-content\/uploads\/2019\/03\/atm_other.png 922w\" sizes=\"(max-width: 300px) 100vw, 300px\" \/><\/div><\/div><\/div><\/div><\/div>\n\n\n\n<h3 class=\"wp-block-heading\">Related links<\/h3>\n\n\n\n<div class=\"wp-block-ugb-icon-list ugb-icon-list ugb-40651a2 ugb-icon-list--v2 ugb-icon--icon-arrow ugb-main-block\" id=\"\"><style>.ugb-40651a2 li{--icon-size:20px;margin-bottom:0px !important}.ugb-40651a2 li::before{height:20px !important;width:20px !important;background-image:url('data:image\/svg+xml;base64,PHN2ZyB2aWV3Qm94PSIwIDAgMTkwIDE5MCIgeG1sbnM9Imh0dHA6Ly93d3cudzMub3JnLzIwMDAvc3ZnIiBzdHlsZT0iZmlsbDojMDBkMDg0Ij48cGF0aCBkPSJNNTkuNCAxNzcuNWw4Mi40LTgyLjQtODIuNC04Mi4zLTEwLjYgMTAuNiA3MS44IDcxLjctNzEuOCA3MS44IDEwLjYgMTAuNnoiPjwvcGF0aD48L3N2Zz4=')}.ugb-40651a2 li ul{margin-bottom:0px !important}.ugb-40651a2.ugb-icon-list ul{columns:1}<\/style><div class=\"ugb-inner-block\"><div class=\"ugb-block-content\"><ul><li>More information about the <a rel=\"noreferrer noopener\" href=\"https:\/\/cab.inta-csic.es\/users\/jrpardo\/atm.html\" target=\"_blank\">ATM model<\/a> (by J. Pardo)<\/li><li>The <a rel=\"noreferrer noopener\" href=\"https:\/\/doi.org\/10.5281\/zenodo.3406496\" target=\"_blank\">am atmospheric model<\/a> (S. Paine). You can find <a rel=\"noreferrer noopener\" href=\"https:\/\/www.cfa.harvard.edu\/~spaine\/am\/\" target=\"_blank\">the code and documentation at the CfA web pages<\/a>.<\/li><li><a rel=\"noreferrer noopener\" href=\"https:\/\/science.nrao.edu\/facilities\/alma\/aboutALMA\/Technology\/ALMA_Memo_Series\" target=\"_blank\">ALMA Memo series<\/a>. In particular <a rel=\"noreferrer noopener\" href=\"http:\/\/www.alma.nrao.edu\/memos\/html-memos\/abstracts\/abs521.html\" target=\"_blank\">521<\/a>, <a rel=\"noreferrer noopener\" href=\"http:\/\/legacy.nrao.edu\/alma\/memos\/html-memos\/abstracts\/abs512.html\" target=\"_blank\">512<\/a>, <a rel=\"noreferrer noopener\" href=\"http:\/\/legacy.nrao.edu\/alma\/memos\/html-memos\/abstracts\/abs384.html\" target=\"_blank\">382<\/a> and <a rel=\"noreferrer noopener\" href=\"http:\/\/legacy.nrao.edu\/alma\/memos\/html-memos\/abstracts\/abs187.html\" target=\"_blank\">187<\/a>.<\/li><\/ul><\/div><\/div><\/div>\n\n\n\n<div class=\"wp-block-group\"><div class=\"wp-block-group__inner-container is-layout-flow wp-block-group-is-layout-flow\">\n<div style=\"height:20px\" aria-hidden=\"true\" class=\"wp-block-spacer\"><\/div>\n<\/div><\/div>\n\n\n\n<hr class=\"wp-block-separator has-css-opacity is-style-wide\"\/>\n\n\n\n<h2 class=\"wp-block-heading\">Forecast and satellite imagery<\/h2>\n\n\n\n<p>Here there are some links to relevant weather forecasts<\/p>\n\n\n\n<div class=\"wp-block-ugb-icon-list ugb-icon-list ugb-b05c0e4 ugb-icon-list--v2 ugb-icon--icon-arrow ugb-main-block\" id=\"\"><style>.ugb-b05c0e4 li{--icon-size:20px;margin-bottom:5px !important}.ugb-b05c0e4 li::before{height:20px !important;width:20px !important;background-image:url('data:image\/svg+xml;base64,PHN2ZyB2aWV3Qm94PSIwIDAgMTkwIDE5MCIgeG1sbnM9Imh0dHA6Ly93d3cudzMub3JnLzIwMDAvc3ZnIiBzdHlsZT0iZmlsbDojMDBkMDg0Ij48cGF0aCBkPSJNNTkuNCAxNzcuNWw4Mi40LTgyLjQtODIuNC04Mi4zLTEwLjYgMTAuNiA3MS44IDcxLjctNzEuOCA3MS44IDEwLjYgMTAuNnoiPjwvcGF0aD48L3N2Zz4=')}.ugb-b05c0e4 li ul{margin-bottom:5px !important}.ugb-b05c0e4.ugb-icon-list ul{columns:1}<\/style><div class=\"ugb-inner-block\"><div class=\"ugb-block-content\"><ul><li><a rel=\"noreferrer noopener\" aria-label=\"PWV forecast from the GFS (Global Forecast System) model (opens in a new tab)\" href=\"http:\/\/www.eso.org\/gen-fac\/pubs\/astclim\/forecast\/gfs\/APEX\/\" target=\"_blank\">PWV forecast from the GFS (Global Forecast System) model<\/a><\/li><li><a rel=\"noreferrer noopener\" aria-label=\"Direcci\u00f3n Meteorol\u00f3gica de Chile (opens in a new tab)\" href=\"http:\/\/www.meteochile.cl\/PortalDMC-web\/otros_pronosticos\/pronostico_cordillera.xhtml\" target=\"_blank\">Direcci\u00f3n Meteorol\u00f3gica de Chile<\/a>. Pron\u00f3sticos-Cordillera, Antofagasta Region (in Spanish)<\/li><li><a href=\"http:\/\/www.apex-telescope.org\/weather\/RadioMeter\/index.php\" target=\"_blank\" rel=\"noreferrer noopener\">PWV radiometer measurements on top of GFS forecast<\/a><\/li><li><a rel=\"noreferrer noopener\" aria-label=\"ALMA weather stations (opens in a new tab)\" href=\"http:\/\/weather.aiv.alma.cl\/all\/30min.php\" target=\"_blank\">ALMA weather stations<\/a> (ESO intranet)<\/li><li><a rel=\"noreferrer noopener\" aria-label=\"Yr.no (opens in a new tab)\" href=\"https:\/\/www.yr.no\/place\/Bolivia\/Potos%C3%AD\/Cerro_Chajnantor\/\" target=\"_blank\">Yr.no<\/a> (Norwegian Meteorological Institute and the Norwegian Broadcasting Corporation)<\/li><li><a rel=\"noreferrer noopener\" aria-label=\"Meteogram from Windy.com (opens in a new tab)\" href=\"https:\/\/www.windy.com\/-23.008\/-67.759\/meteogram?-23.072,-67.724,12\" target=\"_blank\">Meteogram from Windy.com<\/a><\/li><\/ul><\/div><\/div><\/div>\n\n\n\n<p>And here you find links to some interesting sites with relevant satellite images<\/p>\n\n\n\n<div class=\"wp-block-ugb-icon-list ugb-icon-list ugb-e99d539 ugb-icon-list--v2 ugb-icon--icon-arrow ugb-main-block\" id=\"\"><style>.ugb-e99d539 li{--icon-size:20px;margin-bottom:5px !important}.ugb-e99d539 li::before{height:20px !important;width:20px !important;background-image:url('data:image\/svg+xml;base64,PHN2ZyB2aWV3Qm94PSIwIDAgMTkwIDE5MCIgeG1sbnM9Imh0dHA6Ly93d3cudzMub3JnLzIwMDAvc3ZnIiBzdHlsZT0iZmlsbDojMDBkMDg0Ij48cGF0aCBkPSJNNTkuNCAxNzcuNWw4Mi40LTgyLjQtODIuNC04Mi4zLTEwLjYgMTAuNiA3MS44IDcxLjctNzEuOCA3MS44IDEwLjYgMTAuNnoiPjwvcGF0aD48L3N2Zz4=')}.ugb-e99d539 li ul{margin-bottom:5px !important}.ugb-e99d539.ugb-icon-list ul{columns:1}<\/style><div class=\"ugb-inner-block\"><div class=\"ugb-block-content\"><ul><li><a rel=\"noreferrer noopener\" aria-label=\"Satellite imagery @ ESO (opens in a new tab)\" href=\"http:\/\/www.eso.org\/gen-fac\/pubs\/astclim\/forecast\/meteo\/CIRA\/\" target=\"_blank\">Satellite imagery @ ESO<\/a>. Source NOAA \/ NESDIS. GOES-16 ABI<\/li><li><a rel=\"noreferrer noopener\" aria-label=\"Wunderground.com Global infrared satellite (South America) (opens in a new tab)\" href=\"https:\/\/www.wunderground.com\/maps\/satellite\/infrared\/samer\" target=\"_blank\">Wunderground.com Global infrared satellite (South America)<\/a><\/li><li><a rel=\"noreferrer noopener\" aria-label=\"NRL Monterrey Global Imagery (opens in a new tab)\" href=\"https:\/\/www.nrlmry.navy.mil\/sat-bin\/display10.cgi?SIZE=thumb&amp;PHOT=yes&amp;AREA=global\/eastern_pacific&amp;PROD=vapor&amp;TYPE=&amp;NAV=global&amp;DISPLAY=Latest\" target=\"_blank\">NRL Monterrey Global Imagery<\/a> <\/li><li><a rel=\"noreferrer noopener\" aria-label=\"Infrared composite image (opens in a new tab)\" href=\"https:\/\/www.ssec.wisc.edu\/data\/comp\/latest_moll.gif\" target=\"_blank\">Infrared composite image<\/a> from SSEC (Univ. of Wisconsin-Madison) <\/li><li><a href=\"http:\/\/www.spacewx.com\/Space_Weather_Now.html\" target=\"_blank\" rel=\"noreferrer noopener\" aria-label=\"Space Weather now (opens in a new tab)\">Space Weather now<\/a><\/li><\/ul><\/div><\/div><\/div>\n\n\n\n<hr class=\"wp-block-separator has-css-opacity is-style-wide\"\/>\n\n\n\n<div style=\"height:100px\" aria-hidden=\"true\" class=\"wp-block-spacer\"><\/div>\n","protected":false},"excerpt":{"rendered":"<p>The precipitable water vapour (PWV) is the crucial parameter that determines the atmospheric transparency for sub-millimetre observations. At the APEX site on Llano de Chajnantor the amount of PWV is typically 1.0 mm and falls below 0.5 mm up to <a href=\"https:\/\/www.apex-telescope.org\/ns\/observing\/weather\/\" class=\"read-more\">Read More &#8230;<\/a><\/p>\n","protected":false},"author":1,"featured_media":0,"parent":39,"menu_order":0,"comment_status":"closed","ping_status":"closed","template":"","meta":{"ngg_post_thumbnail":0,"spay_email":"","footnotes":""},"class_list":["post-105","page","type-page","status-publish","hentry"],"featured_image_urls":{"full":"","thumbnail":"","medium":"","medium_large":"","large":"","1536x1536":"","2048x2048":"","education-hub-thumb":""},"post_excerpt_stackable":"<p>The precipitable water vapour (PWV) is the crucial parameter that determines the atmospheric transparency for sub-millimetre observations. At the APEX site on Llano de Chajnantor the amount of PWV is typically 1.0 mm and falls below 0.5 mm up to 25% of the time. Weather data Check here the current weather conditions at the APEX site in Chajnantor: PWV, temperature, humidity, pressure, wind speed. Access also historical data&#8230;Go Atmospheric transmission To prepare the observations and make time estimates for different atmospheric conditions check our instrument setup tool, based on the\u00a0ATM model\u00a0. You can find here an interface to check only&hellip;<\/p>\n","category_list":"","author_info":{"name":"apex","url":"https:\/\/www.apex-telescope.org\/ns\/author\/apex\/"},"comments_num":"0 comments","featured_image_urls_v2":{"full":"","thumbnail":"","medium":"","medium_large":"","large":"","1536x1536":"","2048x2048":"","education-hub-thumb":""},"post_excerpt_stackable_v2":"<p>The precipitable water vapour (PWV) is the crucial parameter that determines the atmospheric transparency for sub-millimetre observations. At the APEX site on Llano de Chajnantor the amount of PWV is typically 1.0 mm and falls below 0.5 mm up to 25% of the time. Weather data Check here the current weather conditions at the APEX site in Chajnantor: PWV, temperature, humidity, pressure, wind speed. Access also historical data&#8230;Go Atmospheric transmission To prepare the observations and make time estimates for different atmospheric conditions check our instrument setup tool, based on the\u00a0ATM model\u00a0. You can find here an interface to check only&hellip;<\/p>\n","category_list_v2":"","author_info_v2":{"name":"apex","url":"https:\/\/www.apex-telescope.org\/ns\/author\/apex\/"},"comments_num_v2":"0 comments","_links":{"self":[{"href":"https:\/\/www.apex-telescope.org\/ns\/wp-json\/wp\/v2\/pages\/105","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.apex-telescope.org\/ns\/wp-json\/wp\/v2\/pages"}],"about":[{"href":"https:\/\/www.apex-telescope.org\/ns\/wp-json\/wp\/v2\/types\/page"}],"author":[{"embeddable":true,"href":"https:\/\/www.apex-telescope.org\/ns\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.apex-telescope.org\/ns\/wp-json\/wp\/v2\/comments?post=105"}],"version-history":[{"count":39,"href":"https:\/\/www.apex-telescope.org\/ns\/wp-json\/wp\/v2\/pages\/105\/revisions"}],"predecessor-version":[{"id":5102,"href":"https:\/\/www.apex-telescope.org\/ns\/wp-json\/wp\/v2\/pages\/105\/revisions\/5102"}],"up":[{"embeddable":true,"href":"https:\/\/www.apex-telescope.org\/ns\/wp-json\/wp\/v2\/pages\/39"}],"wp:attachment":[{"href":"https:\/\/www.apex-telescope.org\/ns\/wp-json\/wp\/v2\/media?parent=105"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}