{"id":16803,"date":"2026-06-22T04:02:29","date_gmt":"2026-06-22T04:02:29","guid":{"rendered":"https:\/\/siliconvalleymovingpost.com\/?p=16803"},"modified":"2026-06-22T04:02:29","modified_gmt":"2026-06-22T04:02:29","slug":"experts-explain-why-air-quality-readings-differ-during-boyle-heights-fire","status":"publish","type":"post","link":"https:\/\/siliconvalleymovingpost.com\/?p=16803","title":{"rendered":"Experts explain why air quality readings differ during Boyle Heights fire"},"content":{"rendered":"
\n

Residents checking air quality Sunday as smoke from the Boyle Heights cold-storage warehouse fire drifted across Southern California may have found very different answers depending on which website or app they consulted.<\/p>\n

Read more Company where Boyle Heights facility is burning gives $2 million to the community<\/a><\/p>\n

One source showed unhealthy air in parts of Pasadena while another rated conditions as fair or moderate, raising questions about what data to trust.<\/p>\n

Experts say different readings don\u2019t necessarily mean one source is wrong. Instead, they can reflect differences in where monitors are located, how frequently they update, the methods used to calculate air quality and rapidly shifting smoke carried by changing winds.<\/p>\n

As the warehouse fire continued to burn Sunday, the South Coast Air Quality Management District extended its Special Particle Pollution Advisory through Monday at 12:30 p.m., warning that smoke could continue affecting communities beyond Boyle Heights.<\/p>\n

\u201cThe atmosphere is very dynamic,\u201d John Crounse, a research scientist at California Institute of Technology who leads the team behind the institute\u2019s air quality monitoring station, said Sunday.<\/p>\n

He said the warehouse can be thought of as a single point source of pollution. Rather than spreading evenly across Southern California, the smoke largely follows the direction of the wind, meaning neighborhoods directly downwind may experience much poorer air quality while communities only a few miles away can see much clearer conditions.<\/p>\n

That pattern was reflected in Sunday\u2019s weather forecast, said David Gomberg, lead meteorologist at the National Weather Service office in Los Angeles\/Oxnard.<\/p>\n

An onshore sea breeze was expected to push smoke and pollutants primarily east and northeast of Boyle Heights, with the greatest impacts extending into the San Gabriel Valley and farther east into parts of San Bernardino and Riverside counties, he said.<\/p>\n

\n<\/div>\n

\u201cThe wind today is coming from kind of an onshore sea breeze, so that\u2019s coming more from the southwest to west direction,\u201d Gomberg said. \u201cThat means that locations to the east and northeast are going to be most impacted by the smoke and the pollutants.\u201d<\/p>\n

Gomberg said some smoke could also drift into portions of the San Fernando Valley and the L.A. basin during the morning because of a brief overnight wind reversal before the stronger daytime sea breeze becomes dominant.<\/p>\n

Where many readers become confused, experts said, is that different services aren\u2019t always measuring or displaying air quality in the same way.<\/p>\n

Read more Zach Neto\u2019s 9th-inning homer lifts Angels past A\u2019s<\/a><\/p>\n

According to Nahal Mogharabi, a spokesperson for the South Coast Air Quality Management District, the agency\u2019s air quality map combines data from regulatory monitors, temporary regulatory monitors deployed specifically for the Boyle Heights fire and a network of calibrated air quality sensors. The agency also uses U.S. Environmental Protection Agency-established methods to calculate the Air Quality Index.<\/p>\n

\n<\/div>\n

Other services, Mogharabi said, may rely on different monitoring networks, different calculation methods or broader computer models that are less suited for neighborhood-level conditions in Southern California\u2019s complex terrain.<\/p>\n

Caltech\u2019s monitor is designed for a different purpose altogether. Crounse said the station reports air quality using measurements from the previous 30 minutes to provide near-real-time information for people deciding whether to exercise or spend time outdoors, rather than relying on longer averaging periods that can smooth out rapid changes.<\/p>\n

That approach was reflected Sunday morning, when Caltech\u2019s monitor showed air quality in Pasadena deteriorating sharply around 9 a.m. before improving dramatically by mid-morning.<\/p>\n

Crounse said the rapid shift was driven by changing winds that carried the smoke plume through Pasadena before moving it elsewhere.<\/p>\n

\u201cThe wind in Los Angeles will change fairly regularly as a time of day,\u201d Crounse said. \u201cThey certainly can explain why you might see smoke at 9 a.m. \u2026 and then there\u2019s no smoke at 11 a.m. That\u2019s just an effect due to the winds changing.\u201d<\/p>\n

That also means residents shouldn\u2019t assume a reading from one monitor represents conditions across the region.<\/p>\n

\u201cI would say, at first take, believe the numbers that you see,\u201d Crounse said, noting that those readings may represent pollution averaged over a period of time and apply to the area immediately surrounding the monitor.<\/p>\n

AQMD recommends residents rely on vetted air quality sources that use established scientific methods and to take precautions if they see or smell smoke at ground level.<\/p>\n

Crounse offered similar advice.<\/p>\n

\u201cIf it smells bad and looks bad, but still, the air quality number you read is good,\u201d he said, \u201cwell, trust your senses.\u201d<\/p>\n

Read more Dads get the gift of gleaming chrome at Father\u2019s Day car show in Brea<\/a><\/p>\n<\/div>\n","protected":false},"excerpt":{"rendered":"

Confused by conflicting air quality readings after the Boyle Heights warehouse fire? Experts explain why different maps vary and how to interpret them.<\/p>\n","protected":false},"author":1,"featured_media":16802,"comment_status":"open","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[43,2],"tags":[],"class_list":["post-16803","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-based-on-facts-either-observed-and-verified-directly-by-the-reporter-or-reported-and-verified-from-knowledgeable-sources","category-news"],"yoast_head":"\nExperts explain why air quality readings differ during Boyle Heights fire - Silicon Valley Moving Post<\/title>\n<meta name=\"robots\" content=\"index, follow, max-snippet:-1, max-image-preview:large, max-video-preview:-1\" \/>\n<link rel=\"canonical\" href=\"https:\/\/siliconvalleymovingpost.com\/?p=16803\" \/>\n<meta property=\"og:locale\" content=\"en_US\" \/>\n<meta property=\"og:type\" content=\"article\" \/>\n<meta property=\"og:title\" content=\"Experts explain why air quality readings differ during Boyle Heights fire - Silicon Valley Moving Post\" \/>\n<meta property=\"og:description\" content=\"Confused by conflicting air quality readings after the Boyle Heights warehouse fire? Experts explain why different maps vary and how to interpret them.\" \/>\n<meta property=\"og:url\" content=\"https:\/\/siliconvalleymovingpost.com\/?p=16803\" \/>\n<meta property=\"og:site_name\" content=\"Silicon Valley Moving Post\" \/>\n<meta property=\"article:published_time\" content=\"2026-06-22T04:02:29+00:00\" \/>\n<meta name=\"author\" content=\"admin\" \/>\n<meta name=\"twitter:card\" content=\"summary_large_image\" \/>\n<meta name=\"twitter:label1\" content=\"Written by\" \/>\n\t<meta name=\"twitter:data1\" content=\"admin\" \/>\n\t<meta name=\"twitter:label2\" content=\"Est. reading time\" \/>\n\t<meta name=\"twitter:data2\" content=\"4 minutes\" \/>\n<script type=\"application\/ld+json\" class=\"yoast-schema-graph\">{\"@context\":\"https:\\\/\\\/schema.org\",\"@graph\":[{\"@type\":\"Article\",\"@id\":\"https:\\\/\\\/siliconvalleymovingpost.com\\\/?p=16803#article\",\"isPartOf\":{\"@id\":\"https:\\\/\\\/siliconvalleymovingpost.com\\\/?p=16803\"},\"author\":{\"name\":\"admin\",\"@id\":\"https:\\\/\\\/siliconvalleymovingpost.com\\\/#\\\/schema\\\/person\\\/636e2e5a10a21cf87fe6eb5951e8a6b7\"},\"headline\":\"Experts explain why air quality readings differ during Boyle Heights fire\",\"datePublished\":\"2026-06-22T04:02:29+00:00\",\"mainEntityOfPage\":{\"@id\":\"https:\\\/\\\/siliconvalleymovingpost.com\\\/?p=16803\"},\"wordCount\":779,\"commentCount\":0,\"image\":{\"@id\":\"https:\\\/\\\/siliconvalleymovingpost.com\\\/?p=16803#primaryimage\"},\"thumbnailUrl\":\"https:\\\/\\\/siliconvalleymovingpost.com\\\/wp-content\\\/uploads\\\/2026\\\/06\\\/9a932586cbf05d65b5d5338db0e5914b.webp\",\"articleSection\":[\"Based on facts, either observed and verified directly by the reporter, or reported and verified from knowledgeable sources.\",\"News\"],\"inLanguage\":\"en-US\",\"potentialAction\":[{\"@type\":\"CommentAction\",\"name\":\"Comment\",\"target\":[\"https:\\\/\\\/siliconvalleymovingpost.com\\\/?p=16803#respond\"]}]},{\"@type\":\"WebPage\",\"@id\":\"https:\\\/\\\/siliconvalleymovingpost.com\\\/?p=16803\",\"url\":\"https:\\\/\\\/siliconvalleymovingpost.com\\\/?p=16803\",\"name\":\"Experts explain why air quality readings differ during Boyle Heights fire - Silicon Valley Moving Post\",\"isPartOf\":{\"@id\":\"https:\\\/\\\/siliconvalleymovingpost.com\\\/#website\"},\"primaryImageOfPage\":{\"@id\":\"https:\\\/\\\/siliconvalleymovingpost.com\\\/?p=16803#primaryimage\"},\"image\":{\"@id\":\"https:\\\/\\\/siliconvalleymovingpost.com\\\/?p=16803#primaryimage\"},\"thumbnailUrl\":\"https:\\\/\\\/siliconvalleymovingpost.com\\\/wp-content\\\/uploads\\\/2026\\\/06\\\/9a932586cbf05d65b5d5338db0e5914b.webp\",\"datePublished\":\"2026-06-22T04:02:29+00:00\",\"author\":{\"@id\":\"https:\\\/\\\/siliconvalleymovingpost.com\\\/#\\\/schema\\\/person\\\/636e2e5a10a21cf87fe6eb5951e8a6b7\"},\"breadcrumb\":{\"@id\":\"https:\\\/\\\/siliconvalleymovingpost.com\\\/?p=16803#breadcrumb\"},\"inLanguage\":\"en-US\",\"potentialAction\":[{\"@type\":\"ReadAction\",\"target\":[\"https:\\\/\\\/siliconvalleymovingpost.com\\\/?p=16803\"]}]},{\"@type\":\"ImageObject\",\"inLanguage\":\"en-US\",\"@id\":\"https:\\\/\\\/siliconvalleymovingpost.com\\\/?p=16803#primaryimage\",\"url\":\"https:\\\/\\\/siliconvalleymovingpost.com\\\/wp-content\\\/uploads\\\/2026\\\/06\\\/9a932586cbf05d65b5d5338db0e5914b.webp\",\"contentUrl\":\"https:\\\/\\\/siliconvalleymovingpost.com\\\/wp-content\\\/uploads\\\/2026\\\/06\\\/9a932586cbf05d65b5d5338db0e5914b.webp\",\"width\":1024,\"height\":638},{\"@type\":\"BreadcrumbList\",\"@id\":\"https:\\\/\\\/siliconvalleymovingpost.com\\\/?p=16803#breadcrumb\",\"itemListElement\":[{\"@type\":\"ListItem\",\"position\":1,\"name\":\"Home\",\"item\":\"https:\\\/\\\/siliconvalleymovingpost.com\\\/\"},{\"@type\":\"ListItem\",\"position\":2,\"name\":\"Experts explain why air quality readings differ during Boyle Heights fire\"}]},{\"@type\":\"WebSite\",\"@id\":\"https:\\\/\\\/siliconvalleymovingpost.com\\\/#website\",\"url\":\"https:\\\/\\\/siliconvalleymovingpost.com\\\/\",\"name\":\"Silicon Valley Moving Post\",\"description\":\"\",\"potentialAction\":[{\"@type\":\"SearchAction\",\"target\":{\"@type\":\"EntryPoint\",\"urlTemplate\":\"https:\\\/\\\/siliconvalleymovingpost.com\\\/?s={search_term_string}\"},\"query-input\":{\"@type\":\"PropertyValueSpecification\",\"valueRequired\":true,\"valueName\":\"search_term_string\"}}],\"inLanguage\":\"en-US\"},{\"@type\":\"Person\",\"@id\":\"https:\\\/\\\/siliconvalleymovingpost.com\\\/#\\\/schema\\\/person\\\/636e2e5a10a21cf87fe6eb5951e8a6b7\",\"name\":\"admin\",\"image\":{\"@type\":\"ImageObject\",\"inLanguage\":\"en-US\",\"@id\":\"https:\\\/\\\/secure.gravatar.com\\\/avatar\\\/50b1ad2e498f523425ee0a8cc5180a210646db1622662a3d56cc405d3e0c346a?s=96&d=mm&r=g\",\"url\":\"https:\\\/\\\/secure.gravatar.com\\\/avatar\\\/50b1ad2e498f523425ee0a8cc5180a210646db1622662a3d56cc405d3e0c346a?s=96&d=mm&r=g\",\"contentUrl\":\"https:\\\/\\\/secure.gravatar.com\\\/avatar\\\/50b1ad2e498f523425ee0a8cc5180a210646db1622662a3d56cc405d3e0c346a?s=96&d=mm&r=g\",\"caption\":\"admin\"},\"sameAs\":[\"http:\\\/\\\/siliconvalleymovingpost.com\"],\"url\":\"https:\\\/\\\/siliconvalleymovingpost.com\\\/?author=1\"}]}<\/script>\n<!-- \/ Yoast SEO plugin. -->","yoast_head_json":{"title":"Experts explain why air quality readings differ during Boyle Heights fire - Silicon Valley Moving Post","robots":{"index":"index","follow":"follow","max-snippet":"max-snippet:-1","max-image-preview":"max-image-preview:large","max-video-preview":"max-video-preview:-1"},"canonical":"https:\/\/siliconvalleymovingpost.com\/?p=16803","og_locale":"en_US","og_type":"article","og_title":"Experts explain why air quality readings differ during Boyle Heights fire - Silicon Valley Moving Post","og_description":"Confused by conflicting air quality readings after the Boyle Heights warehouse fire? Experts explain why different maps vary and how to interpret them.","og_url":"https:\/\/siliconvalleymovingpost.com\/?p=16803","og_site_name":"Silicon Valley Moving Post","article_published_time":"2026-06-22T04:02:29+00:00","author":"admin","twitter_card":"summary_large_image","twitter_misc":{"Written by":"admin","Est. reading time":"4 minutes"},"schema":{"@context":"https:\/\/schema.org","@graph":[{"@type":"Article","@id":"https:\/\/siliconvalleymovingpost.com\/?p=16803#article","isPartOf":{"@id":"https:\/\/siliconvalleymovingpost.com\/?p=16803"},"author":{"name":"admin","@id":"https:\/\/siliconvalleymovingpost.com\/#\/schema\/person\/636e2e5a10a21cf87fe6eb5951e8a6b7"},"headline":"Experts explain why air quality readings differ during Boyle Heights fire","datePublished":"2026-06-22T04:02:29+00:00","mainEntityOfPage":{"@id":"https:\/\/siliconvalleymovingpost.com\/?p=16803"},"wordCount":779,"commentCount":0,"image":{"@id":"https:\/\/siliconvalleymovingpost.com\/?p=16803#primaryimage"},"thumbnailUrl":"https:\/\/siliconvalleymovingpost.com\/wp-content\/uploads\/2026\/06\/9a932586cbf05d65b5d5338db0e5914b.webp","articleSection":["Based on facts, either observed and verified directly by the reporter, or reported and verified from knowledgeable sources.","News"],"inLanguage":"en-US","potentialAction":[{"@type":"CommentAction","name":"Comment","target":["https:\/\/siliconvalleymovingpost.com\/?p=16803#respond"]}]},{"@type":"WebPage","@id":"https:\/\/siliconvalleymovingpost.com\/?p=16803","url":"https:\/\/siliconvalleymovingpost.com\/?p=16803","name":"Experts explain why air quality readings differ during Boyle Heights fire - Silicon Valley Moving Post","isPartOf":{"@id":"https:\/\/siliconvalleymovingpost.com\/#website"},"primaryImageOfPage":{"@id":"https:\/\/siliconvalleymovingpost.com\/?p=16803#primaryimage"},"image":{"@id":"https:\/\/siliconvalleymovingpost.com\/?p=16803#primaryimage"},"thumbnailUrl":"https:\/\/siliconvalleymovingpost.com\/wp-content\/uploads\/2026\/06\/9a932586cbf05d65b5d5338db0e5914b.webp","datePublished":"2026-06-22T04:02:29+00:00","author":{"@id":"https:\/\/siliconvalleymovingpost.com\/#\/schema\/person\/636e2e5a10a21cf87fe6eb5951e8a6b7"},"breadcrumb":{"@id":"https:\/\/siliconvalleymovingpost.com\/?p=16803#breadcrumb"},"inLanguage":"en-US","potentialAction":[{"@type":"ReadAction","target":["https:\/\/siliconvalleymovingpost.com\/?p=16803"]}]},{"@type":"ImageObject","inLanguage":"en-US","@id":"https:\/\/siliconvalleymovingpost.com\/?p=16803#primaryimage","url":"https:\/\/siliconvalleymovingpost.com\/wp-content\/uploads\/2026\/06\/9a932586cbf05d65b5d5338db0e5914b.webp","contentUrl":"https:\/\/siliconvalleymovingpost.com\/wp-content\/uploads\/2026\/06\/9a932586cbf05d65b5d5338db0e5914b.webp","width":1024,"height":638},{"@type":"BreadcrumbList","@id":"https:\/\/siliconvalleymovingpost.com\/?p=16803#breadcrumb","itemListElement":[{"@type":"ListItem","position":1,"name":"Home","item":"https:\/\/siliconvalleymovingpost.com\/"},{"@type":"ListItem","position":2,"name":"Experts explain why air quality readings differ during Boyle Heights fire"}]},{"@type":"WebSite","@id":"https:\/\/siliconvalleymovingpost.com\/#website","url":"https:\/\/siliconvalleymovingpost.com\/","name":"Silicon Valley Moving Post","description":"","potentialAction":[{"@type":"SearchAction","target":{"@type":"EntryPoint","urlTemplate":"https:\/\/siliconvalleymovingpost.com\/?s={search_term_string}"},"query-input":{"@type":"PropertyValueSpecification","valueRequired":true,"valueName":"search_term_string"}}],"inLanguage":"en-US"},{"@type":"Person","@id":"https:\/\/siliconvalleymovingpost.com\/#\/schema\/person\/636e2e5a10a21cf87fe6eb5951e8a6b7","name":"admin","image":{"@type":"ImageObject","inLanguage":"en-US","@id":"https:\/\/secure.gravatar.com\/avatar\/50b1ad2e498f523425ee0a8cc5180a210646db1622662a3d56cc405d3e0c346a?s=96&d=mm&r=g","url":"https:\/\/secure.gravatar.com\/avatar\/50b1ad2e498f523425ee0a8cc5180a210646db1622662a3d56cc405d3e0c346a?s=96&d=mm&r=g","contentUrl":"https:\/\/secure.gravatar.com\/avatar\/50b1ad2e498f523425ee0a8cc5180a210646db1622662a3d56cc405d3e0c346a?s=96&d=mm&r=g","caption":"admin"},"sameAs":["http:\/\/siliconvalleymovingpost.com"],"url":"https:\/\/siliconvalleymovingpost.com\/?author=1"}]}},"_links":{"self":[{"href":"https:\/\/siliconvalleymovingpost.com\/index.php?rest_route=\/wp\/v2\/posts\/16803","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/siliconvalleymovingpost.com\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/siliconvalleymovingpost.com\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/siliconvalleymovingpost.com\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/siliconvalleymovingpost.com\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=16803"}],"version-history":[{"count":0,"href":"https:\/\/siliconvalleymovingpost.com\/index.php?rest_route=\/wp\/v2\/posts\/16803\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/siliconvalleymovingpost.com\/index.php?rest_route=\/wp\/v2\/media\/16802"}],"wp:attachment":[{"href":"https:\/\/siliconvalleymovingpost.com\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=16803"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/siliconvalleymovingpost.com\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=16803"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/siliconvalleymovingpost.com\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=16803"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}