{"id":12,"date":"2019-09-03T00:00:00","date_gmt":"2019-09-03T00:00:00","guid":{"rendered":"https:\/\/lazysurfer.app\/blog\/?p=12"},"modified":"2021-02-27T17:36:53","modified_gmt":"2021-02-27T17:36:53","slug":"reading-surf-forecasts-swell-height-911970022082","status":"publish","type":"post","link":"https:\/\/lazysurfer.app\/blog\/reading-surf-forecasts-swell-height-911970022082\/","title":{"rendered":"Reading Surf Forecasts: Swell\u00a0Height"},"content":{"rendered":"<figure>\n<p><figure style=\"width: 800px\" class=\"wp-caption alignnone\"><img data-recalc-dims=\"1\" loading=\"lazy\" decoding=\"async\" src=\"https:\/\/i0.wp.com\/cdn-images-1.medium.com\/max\/800\/1%2Ai85IracJR3k8hu9N5ilDCg.jpeg?resize=640%2C426&#038;ssl=1\" alt=\"\" width=\"640\" height=\"426\" \/><figcaption class=\"wp-caption-text\">Boone Speed CC BY-SA 4.0<\/figcaption><\/figure><\/figure>\n<p id=\"3d3a\" class=\"graf graf--p graf-after--figure graf--trailing\">This is the third post in a series about reading surf forecasts. Here are the <a class=\"markup--anchor markup--p-anchor\" href=\"https:\/\/lazysurfer.app\/blog\/?p=9\" target=\"_blank\" rel=\"noopener\" data-href=\"https:\/\/medium.com\/@surf.lazy\/reading-surf-forecasts-the-basics-76d25753d82b\">first <\/a>and <a class=\"markup--anchor markup--p-anchor\" href=\"https:\/\/lazysurfer.app\/blog\/?p=8\" target=\"_blank\" rel=\"noopener\" data-href=\"https:\/\/medium.com\/@surf.lazy\/reading-surf-forecasts-what-can-go-wrong-12d435be2f59\">second <\/a>articles.<\/p>\n<p id=\"ae7e\" class=\"graf graf--p graf--leading\">Swell Height[1] is a deceptively difficult thing to measure. The first thing to realize is that this isn\u2019t an objective number\u200a\u2014\u200ait doesn\u2019t correspond one-to-one with any specific <em class=\"markup--em markup--p-em\">thing <\/em>in reality. Instead, it\u2019s a number that should be <em class=\"markup--em markup--p-em\">close to the height of an average wave in some swell<\/em>. I know how squishy and odd that sounds but stick with me because the metric is worth it in the end.<\/p>\n<p id=\"15b7\" class=\"graf graf--p graf-after--p\">So how to get it? You might think, \u201cI\u2019ll get a boat, drive out a ways, drop anchor, sit there for a bit and keep track of the highest and lowest points the ocean surface touched on the anchor line.\u201d<\/p>\n<p id=\"3439\" class=\"graf graf--p graf-after--p\">Nope. That\u2019ll get you the crest of the tallest wave minus the trough of the lowest wave. Odds are good that there was no single wave that was close to as tall as this measurement. Not quite what we want for swell height.<\/p>\n<p id=\"e97e\" class=\"graf graf--p graf--startsWithDoubleQuote graf-after--p\">\u201cWell ok. I\u2019ll sit out there for an hour and write down the heights of all the crests and troughs of all the waves that pass. I\u2019ll then calculate each individual wave height and take the average.\u201d<\/p>\n<figure>\n<p><figure id=\"attachment_29\" aria-describedby=\"caption-attachment-29\" style=\"width: 875px\" class=\"wp-caption aligncenter\"><img data-recalc-dims=\"1\" loading=\"lazy\" decoding=\"async\" class=\"wp-image-29 size-full\" src=\"https:\/\/i0.wp.com\/lazysurfer.app\/blog\/wp-content\/uploads\/2020\/12\/1_09QhBjGm_mRecP1G2ub-Tw.png?resize=640%2C131&#038;ssl=1\" alt=\"\" width=\"640\" height=\"131\" srcset=\"https:\/\/i0.wp.com\/lazysurfer.app\/blog\/wp-content\/uploads\/2020\/12\/1_09QhBjGm_mRecP1G2ub-Tw.png?w=875&amp;ssl=1 875w, https:\/\/i0.wp.com\/lazysurfer.app\/blog\/wp-content\/uploads\/2020\/12\/1_09QhBjGm_mRecP1G2ub-Tw.png?resize=300%2C61&amp;ssl=1 300w, https:\/\/i0.wp.com\/lazysurfer.app\/blog\/wp-content\/uploads\/2020\/12\/1_09QhBjGm_mRecP1G2ub-Tw.png?resize=768%2C157&amp;ssl=1 768w\" sizes=\"auto, (max-width: 640px) 100vw, 640px\" \/><figcaption id=\"caption-attachment-29\" class=\"wp-caption-text\">Here\u2019s what measuring the crests and troughs would look like. Courtesy of CDIP<\/figcaption><\/figure><\/figure>\n<p id=\"da97\" class=\"graf graf--p graf-after--figure\">Closer \u2014you\u2019ve now got a good set of crest-and-trough data through time. The problem here is that you\u2019ll have recorded quite a few very small waves. Including these in the average will result in a very small swell height\u200a\u2014\u200aone that doesn\u2019t capture the intention of the metric.<\/p>\n<p id=\"86e4\" class=\"graf graf--p graf--startsWithDoubleQuote graf-after--p\">\u201cAlrighty, I\u2019ll throw out the smallest two-thirds of the waves and then take the average of the rest.\u201d[2]<\/p>\n<p id=\"adfb\" class=\"graf graf--p graf-after--p\">That&#8217;s an odd suggestion but yes\u200a\u2014\u200ait turns out this tends to give us a number that corresponds well to the close-to-the-height-of-an-average-wave-in-some-swell idea we set out to capture. Unfortunately there\u2019s one more nasty wiggle that you\u2019ve forgotten about\u200a\u2014\u200athere will most likely be multiple swells in the water.<\/p>\n<p id=\"13b5\" class=\"graf graf--p graf--startsWithDoubleQuote graf-after--p\">\u201cUhhhh. How can I tell which swell the wave I\u2019m measuring is part of? They are all jumbled together.\u201d<\/p>\n<p id=\"e0c7\" class=\"graf graf--p graf-after--p\">They sure are. How should we unmelt this gnarly bar of wax that dripped into our car vents and cup holders?<\/p>\n<figure>\n<p><figure id=\"attachment_31\" aria-describedby=\"caption-attachment-31\" style=\"width: 649px\" class=\"wp-caption aligncenter\"><img data-recalc-dims=\"1\" loading=\"lazy\" decoding=\"async\" class=\"wp-image-31 \" src=\"https:\/\/i0.wp.com\/lazysurfer.app\/blog\/wp-content\/uploads\/2019\/09\/1_pfEsiaA9JkPr5t-IZylP-A.png?resize=640%2C302&#038;ssl=1\" alt=\"\" width=\"640\" height=\"302\" srcset=\"https:\/\/i0.wp.com\/lazysurfer.app\/blog\/wp-content\/uploads\/2019\/09\/1_pfEsiaA9JkPr5t-IZylP-A.png?w=545&amp;ssl=1 545w, https:\/\/i0.wp.com\/lazysurfer.app\/blog\/wp-content\/uploads\/2019\/09\/1_pfEsiaA9JkPr5t-IZylP-A.png?resize=300%2C141&amp;ssl=1 300w\" sizes=\"auto, (max-width: 640px) 100vw, 640px\" \/><figcaption id=\"caption-attachment-31\" class=\"wp-caption-text\">MATH<\/figcaption><\/figure><\/figure>\n<p id=\"b58f\" class=\"graf graf--p graf-after--figure\">Math is how. We use the <a class=\"markup--anchor markup--p-anchor\" href=\"https:\/\/en.wikipedia.org\/wiki\/Fourier_transform\" target=\"_blank\" rel=\"noopener\" data-href=\"https:\/\/en.wikipedia.org\/wiki\/Fourier_transform\">Fourier Transform<\/a>[3]. We could spend all day on this puppy but we\u2019re going to say only that it allows us to convert our crest-and-trough data into this[4] \u2014<\/p>\n<figure>\n<p><figure id=\"attachment_34\" aria-describedby=\"caption-attachment-34\" style=\"width: 875px\" class=\"wp-caption alignnone\"><img data-recalc-dims=\"1\" loading=\"lazy\" decoding=\"async\" class=\"size-full wp-image-34\" src=\"https:\/\/i0.wp.com\/lazysurfer.app\/blog\/wp-content\/uploads\/2019\/09\/1_FmduwkVGmkNYMdbQeX8qYA.png?resize=640%2C231&#038;ssl=1\" alt=\"\" width=\"640\" height=\"231\" srcset=\"https:\/\/i0.wp.com\/lazysurfer.app\/blog\/wp-content\/uploads\/2019\/09\/1_FmduwkVGmkNYMdbQeX8qYA.png?w=875&amp;ssl=1 875w, https:\/\/i0.wp.com\/lazysurfer.app\/blog\/wp-content\/uploads\/2019\/09\/1_FmduwkVGmkNYMdbQeX8qYA.png?resize=300%2C108&amp;ssl=1 300w, https:\/\/i0.wp.com\/lazysurfer.app\/blog\/wp-content\/uploads\/2019\/09\/1_FmduwkVGmkNYMdbQeX8qYA.png?resize=768%2C277&amp;ssl=1 768w\" sizes=\"auto, (max-width: 640px) 100vw, 640px\" \/><figcaption id=\"caption-attachment-34\" class=\"wp-caption-text\">DATA<\/figcaption><\/figure><\/figure>\n<p id=\"f884\" class=\"graf graf--p graf-after--figure\">Here\u2019s a plot of a single row of the above data\u2014<\/p>\n<figure>\n<p><figure id=\"attachment_33\" aria-describedby=\"caption-attachment-33\" style=\"width: 726px\" class=\"wp-caption alignnone\"><img data-recalc-dims=\"1\" loading=\"lazy\" decoding=\"async\" class=\"size-full wp-image-33\" src=\"https:\/\/i0.wp.com\/lazysurfer.app\/blog\/wp-content\/uploads\/2019\/09\/1_BUjh8h9LoBS8oDVJAvJ2Ag.png?resize=640%2C353&#038;ssl=1\" alt=\"\" width=\"640\" height=\"353\" srcset=\"https:\/\/i0.wp.com\/lazysurfer.app\/blog\/wp-content\/uploads\/2019\/09\/1_BUjh8h9LoBS8oDVJAvJ2Ag.png?w=726&amp;ssl=1 726w, https:\/\/i0.wp.com\/lazysurfer.app\/blog\/wp-content\/uploads\/2019\/09\/1_BUjh8h9LoBS8oDVJAvJ2Ag.png?resize=300%2C165&amp;ssl=1 300w\" sizes=\"auto, (max-width: 640px) 100vw, 640px\" \/><figcaption id=\"caption-attachment-33\" class=\"wp-caption-text\">Courtesy of CDIP<\/figcaption><\/figure><\/figure>\n<p id=\"4859\" class=\"graf graf--p graf-after--figure\">This plot shows the period (on top) vs. the energy density. You can see that in this case we have a high energy spike at a 15 second period and a bunch of energy in the (less interesting for surfers) 8\u20132 second band.<\/p>\n<p id=\"f265\" class=\"graf graf--p graf-after--p\">In addition to period vs. energy we can use the above plot to get height\u200a\u2014\u200awe would <a class=\"markup--anchor markup--p-anchor\" href=\"https:\/\/en.wikipedia.org\/wiki\/Integral\" target=\"_blank\" rel=\"noopener\" data-href=\"https:\/\/en.wikipedia.org\/wiki\/Integral\">integrate<\/a> under the whole curve to get the height for all swells combined or under a part of the line to get the height for a specific period swell[5].<\/p>\n<p id=\"fb72\" class=\"graf graf--p graf-after--p\">Note that picking a part of the plot that represents \u201cthe 15 second period swell\u201d is not well defined\u200a\u2014\u200ait could be a very narrow band just around 15 seconds, but it also could include the somewhat gentle slopes that go from 18 seconds to 12 seconds. How this is chosen varies among surf forecasts[6].<\/p>\n<p id=\"3ce9\" class=\"graf graf--p graf-after--p\">Fun Sidenote: We can also use the fourier transform to get period vs. swell direction which allows us to generate really cool plots like this \u2014<\/p>\n<figure style=\"padding-left: 80px;\">\n<p><figure id=\"attachment_32\" aria-describedby=\"caption-attachment-32\" style=\"width: 450px\" class=\"wp-caption alignnone\"><img data-recalc-dims=\"1\" loading=\"lazy\" decoding=\"async\" class=\"size-full wp-image-32\" src=\"https:\/\/i0.wp.com\/lazysurfer.app\/blog\/wp-content\/uploads\/2019\/09\/1_Dv6wfOPrsuJzLPP07QLiGg.png?resize=450%2C564&#038;ssl=1\" alt=\"\" width=\"450\" height=\"564\" srcset=\"https:\/\/i0.wp.com\/lazysurfer.app\/blog\/wp-content\/uploads\/2019\/09\/1_Dv6wfOPrsuJzLPP07QLiGg.png?w=450&amp;ssl=1 450w, https:\/\/i0.wp.com\/lazysurfer.app\/blog\/wp-content\/uploads\/2019\/09\/1_Dv6wfOPrsuJzLPP07QLiGg.png?resize=239%2C300&amp;ssl=1 239w\" sizes=\"auto, (max-width: 450px) 100vw, 450px\" \/><figcaption id=\"caption-attachment-32\" class=\"wp-caption-text\">Period vs. Energy Density vs. Direction \u2014 Courtesy of CDIP<\/figcaption><\/figure><\/figure>\n<p id=\"73a2\" class=\"graf graf--p graf--leading\">Finding swell height can be an arduous process and the end result is a pretty squishy metric. Consider that <em class=\"markup--em markup--p-em\">swell height <\/em>is almost meaningless by itself in the sense that no one really cares what the average height of the tallest 1\/3 of waves in a given area are\u200a\u2014\u200awhat we really care about is how tall are the waves compared to yesterday\/last week\/this morning and what is the range of swell heights that make the best waves at our favorite breaks.<\/p>\n<p id=\"ab50\" class=\"graf graf--p graf-after--p graf--trailing\">This last point is one I will continue to stress throughout this series of articles\u200a\u2014\u200a<strong class=\"markup--strong markup--p-strong\">if you want to put yourself in the best position to catch good waves then you must keep track of which conditions work best for each of your local breaks.<\/strong> Too many surfers see 5\u20136 feet on the forecast and run to the closest beach all hot in the biscuit. This is a mistake\u200a\u2014\u200abe more thorough in your study of conditions and you\u2019ll score better surf.<\/p>\n<p>In our <a class=\"markup--anchor markup--p-anchor\" href=\"https:\/\/lazysurfer.app\/blog\/?p=11\" target=\"_blank\" rel=\"noopener\" data-href=\"https:\/\/medium.com\/@help_53076\/reading-surf-forecasts-what-can-go-wrong-12d435be2f59\">next post<\/a>, we\u2019ll talk about how to best use buoy readings to make better decisions about where and when to surf.<\/p>\n<p id=\"749f\" class=\"graf graf--p graf--leading graf--trailing\">Lazy Surfer is the only personalized surf forecasting tool. Download for free today\u200a\u2014\u200a<a class=\"markup--anchor markup--p-anchor\" href=\"https:\/\/lazysurfer.app\/?utm_source=medium&amp;utm_campaign=swell_height\" target=\"_blank\" rel=\"noopener\" data-href=\"https:\/\/lazysurfer.app\/?utm_source=medium&amp;utm_campaign=swell_height\">lazysurfer.app<\/a><\/p>\n<p id=\"b5f3\" class=\"graf graf--p graf--leading\">[1] You might also see the term <em class=\"markup--em markup--p-em\">significant wave height<\/em> (SWH) in forecasts\u200a\u2014\u200aSWH usually encompasses all swells passing through some area of the ocean whereas I\u2019m taking swell height to mean the SWH of a single swell passing through some area.<\/p>\n<p id=\"67a4\" class=\"graf graf--p graf-after--p\">[2] This is <em class=\"markup--em markup--p-em\">almost<\/em> exactly what the NOAA buoys do. The only difference is that <a class=\"markup--anchor markup--p-anchor\" href=\"https:\/\/www.ndbc.noaa.gov\/wave.shtml\" target=\"_blank\" rel=\"noopener\" data-href=\"https:\/\/www.ndbc.noaa.gov\/wave.shtml\">they use accelerometers<\/a> to measure the heights of the individual waves instead of an anchor line. You might remember from Calc I that if you have an initial position and an initial velocity then you can use acceleration measurements over time to get back to position over time.<\/p>\n<p id=\"c180\" class=\"graf graf--p graf-after--p\">[3] The Fourier Transform does a ton of heavy lifting in physics and engineering. The reason it is so useful is that 1). waves are everywhere in nature (ocean, sound, light, radio, bluetooth, wifi, and on and on (those last few are all just different frequencies of electromagnetic waves)) and 2). it allows us gain information about the individual waves that make up a jumbled-up mess of waves. <a href=\"http:\/\/www.jezzamon.com\/fourier\/\">Here&#8217;s a really good explanation of how it works.<\/a><\/p>\n<p id=\"3e94\" class=\"graf graf--p graf-after--p\">[4] This is the raw spectral data from the LJPC1 NOAA buoy on 10:41 8\/20\/2019 UTC. To see the current data go <a class=\"markup--anchor markup--p-anchor\" href=\"https:\/\/www.ndbc.noaa.gov\/data\/realtime2\/LJPC1.data_spec\" target=\"_blank\" rel=\"noopener\" data-href=\"https:\/\/www.ndbc.noaa.gov\/data\/realtime2\/LJPC1.data_spec\">here<\/a>.<\/p>\n<p id=\"fca6\" class=\"graf graf--p graf-after--p\">[5] Note that this isn\u2019t the same as counting all the waves and taking the average of the top 1\/3. In practice though (and only in deep water) it ends up being just about the same with the added benefit of being able to separate out the heights for swells with different periods.<\/p>\n<p id=\"0a61\" class=\"graf graf--p graf-after--p graf--trailing\">[6] NOAA does a very simple split of the frequency range into two halves\u200a\u2014\u200aone is the \u201cswell waves\u201d section and the other is the \u201cwind waves\u201d section. You can see the frequency at which they separate in each row of the <a class=\"markup--anchor markup--p-anchor\" href=\"https:\/\/www.ndbc.noaa.gov\/data\/realtime2\/LJPC1.data_spec\" target=\"_blank\" rel=\"noopener\" data-href=\"https:\/\/www.ndbc.noaa.gov\/data\/realtime2\/LJPC1.data_spec\">spectral data<\/a>. It\u2019s under the header \u201cSep_Freq\u201d. See the \u201cSpectral Wave Data\u201d section <a class=\"markup--anchor markup--p-anchor\" href=\"https:\/\/www.ndbc.noaa.gov\/measdes.shtml\" target=\"_blank\" rel=\"noopener\" data-href=\"https:\/\/www.ndbc.noaa.gov\/measdes.shtml\">here<\/a>.<\/p>\n","protected":false},"excerpt":{"rendered":"<p>This is the third post in a series about reading surf forecasts. Here are the first and second articles. Swell Height[1] is a deceptively difficult thing to measure. The first thing to realize is that this isn\u2019t an objective number\u200a\u2014\u200ait doesn\u2019t correspond one-to-one with any specific thing in reality. Instead, it\u2019s a number that should &hellip; <\/p>\n<p class=\"link-more\"><a href=\"https:\/\/lazysurfer.app\/blog\/reading-surf-forecasts-swell-height-911970022082\/\" class=\"more-link\">Continue reading<span class=\"screen-reader-text\"> &#8220;Reading Surf Forecasts: Swell\u00a0Height&#8221;<\/span><\/a><\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"nf_dc_page":"","om_disable_all_campaigns":false,"_monsterinsights_skip_tracking":false,"_monsterinsights_sitenote_active":false,"_monsterinsights_sitenote_note":"","_monsterinsights_sitenote_category":0,"_jetpack_memberships_contains_paid_content":false,"footnotes":""},"categories":[1],"tags":[],"class_list":["post-12","post","type-post","status-publish","format-standard","hentry","category-uncategorized","entry"],"yoast_head":"<!-- This site is optimized with the Yoast SEO plugin v27.4 - https:\/\/yoast.com\/product\/yoast-seo-wordpress\/ -->\n<title>Reading Surf Forecasts: Swell\u00a0Height - Lazy Surfer Blog<\/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:\/\/lazysurfer.app\/blog\/reading-surf-forecasts-swell-height-911970022082\/\" \/>\n<meta property=\"og:locale\" content=\"en_US\" \/>\n<meta property=\"og:type\" content=\"article\" \/>\n<meta property=\"og:title\" content=\"Reading Surf Forecasts: Swell\u00a0Height - Lazy Surfer Blog\" \/>\n<meta property=\"og:description\" content=\"This is the third post in a series about reading surf forecasts. Here are the first and second articles. Swell Height[1] is a deceptively difficult thing to measure. The first thing to realize is that this isn\u2019t an objective number\u200a\u2014\u200ait doesn\u2019t correspond one-to-one with any specific thing in reality. Instead, it\u2019s a number that should &hellip; Continue reading &quot;Reading Surf Forecasts: Swell\u00a0Height&quot;\" \/>\n<meta property=\"og:url\" content=\"https:\/\/lazysurfer.app\/blog\/reading-surf-forecasts-swell-height-911970022082\/\" \/>\n<meta property=\"og:site_name\" content=\"Lazy Surfer Blog\" \/>\n<meta property=\"article:publisher\" content=\"https:\/\/www.facebook.com\/Surf.Lazy\" \/>\n<meta property=\"article:published_time\" content=\"2019-09-03T00:00:00+00:00\" \/>\n<meta property=\"article:modified_time\" content=\"2021-02-27T17:36:53+00:00\" \/>\n<meta property=\"og:image\" content=\"https:\/\/cdn-images-1.medium.com\/max\/800\/1*i85IracJR3k8hu9N5ilDCg.jpeg\" \/>\n<meta name=\"author\" content=\"Nick Peterson\" \/>\n<meta name=\"twitter:card\" content=\"summary_large_image\" \/>\n<meta name=\"twitter:creator\" content=\"@surferlazy\" \/>\n<meta name=\"twitter:site\" content=\"@surferlazy\" \/>\n<meta name=\"twitter:label1\" content=\"Written by\" \/>\n\t<meta name=\"twitter:data1\" content=\"Nick Peterson\" \/>\n\t<meta name=\"twitter:label2\" content=\"Est. reading time\" \/>\n\t<meta name=\"twitter:data2\" content=\"7 minutes\" \/>\n<script type=\"application\/ld+json\" class=\"yoast-schema-graph\">{\"@context\":\"https:\\\/\\\/schema.org\",\"@graph\":[{\"@type\":\"Article\",\"@id\":\"https:\\\/\\\/lazysurfer.app\\\/blog\\\/reading-surf-forecasts-swell-height-911970022082\\\/#article\",\"isPartOf\":{\"@id\":\"https:\\\/\\\/lazysurfer.app\\\/blog\\\/reading-surf-forecasts-swell-height-911970022082\\\/\"},\"author\":{\"name\":\"Nick Peterson\",\"@id\":\"https:\\\/\\\/lazysurfer.app\\\/blog\\\/#\\\/schema\\\/person\\\/4e3fcab6e7bc54ee6a0efc8043301add\"},\"headline\":\"Reading Surf Forecasts: Swell\u00a0Height\",\"datePublished\":\"2019-09-03T00:00:00+00:00\",\"dateModified\":\"2021-02-27T17:36:53+00:00\",\"mainEntityOfPage\":{\"@id\":\"https:\\\/\\\/lazysurfer.app\\\/blog\\\/reading-surf-forecasts-swell-height-911970022082\\\/\"},\"wordCount\":1177,\"commentCount\":0,\"publisher\":{\"@id\":\"https:\\\/\\\/lazysurfer.app\\\/blog\\\/#organization\"},\"image\":{\"@id\":\"https:\\\/\\\/lazysurfer.app\\\/blog\\\/reading-surf-forecasts-swell-height-911970022082\\\/#primaryimage\"},\"thumbnailUrl\":\"https:\\\/\\\/cdn-images-1.medium.com\\\/max\\\/800\\\/1*i85IracJR3k8hu9N5ilDCg.jpeg\",\"inLanguage\":\"en-US\",\"potentialAction\":[{\"@type\":\"CommentAction\",\"name\":\"Comment\",\"target\":[\"https:\\\/\\\/lazysurfer.app\\\/blog\\\/reading-surf-forecasts-swell-height-911970022082\\\/#respond\"]}]},{\"@type\":\"WebPage\",\"@id\":\"https:\\\/\\\/lazysurfer.app\\\/blog\\\/reading-surf-forecasts-swell-height-911970022082\\\/\",\"url\":\"https:\\\/\\\/lazysurfer.app\\\/blog\\\/reading-surf-forecasts-swell-height-911970022082\\\/\",\"name\":\"Reading Surf Forecasts: Swell\u00a0Height - 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