{"id":802,"date":"2007-08-31T18:59:00","date_gmt":"2007-08-31T18:59:00","guid":{"rendered":"https:\/\/www.starcoder.com\/wordpress\/?p=802"},"modified":"2026-05-09T02:45:47","modified_gmt":"2026-05-09T02:45:47","slug":"precipitation-intensity","status":"publish","type":"post","link":"https:\/\/www.starcoder.com\/wordpress\/2007\/08\/precipitation-intensity\/","title":{"rendered":"Precipitation Intensity"},"content":{"rendered":"\n<p>Today I revisited the code on the Seasonality forecast server that decides on precipitation intensity. I.E., how much rain does it take to have a drizzle, light rain, moderate rain, or heavy rain? This is forecasted in 12 hour blocks, and I take the sum of precipitation over that time frame to get a total precipitation for that block of time.<\/p>\n\n\n\n<p>Previously the intensity chart looked something like this:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>0 &#8211; 3mm: Drizzle<\/li>\n\n\n\n<li>4 &#8211; 7mm: Light Rain<\/li>\n\n\n\n<li>8 &#8211; 25mm: Moderate Rain<\/li>\n\n\n\n<li>> 25mm: Heavy Rain<\/li>\n<\/ul>\n\n\n\n<p>What I found was the GFS model output would often place a millimeter or two of precipitation at random locations and this would trigger a &#8220;drizzle&#8221; forecast far too often. I decided that I needed to revisit the precipitation intensity chart.<\/p>\n\n\n\n<p>I ended up finding&nbsp;<a href=\"http:\/\/www.metoffice.gov.uk\/weather\/uk\/guide\/key.html\">this page<\/a>&nbsp;at the MetOffice (United Kingdom). They have about twice as many intensity categories, from Very slight to Downpour, so I tried to adapt them to my intensity names (which match those of the NDFD forecasts put out by the U.S. National Weather Service). I ended up using these values:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>3 &#8211; 6mm: Drizzle<\/li>\n\n\n\n<li>7 &#8211; 12mm: Light Rain<\/li>\n\n\n\n<li>13 &#8211; 25mm: Moderate Rain<\/li>\n\n\n\n<li>> 25mm: Heavy Rain<\/li>\n<\/ul>\n\n\n\n<p>We&#8217;ll try these out for awhile to see how accurate they are. If you&#8217;re a Seasonality user, these changes were made all on the forecast server, so no software update is necessary.<\/p>\n","protected":false},"excerpt":{"rendered":"<p>Today I revisited the code on the Seasonality forecast server that decides on precipitation intensity. I.E., how much rain does it take to have a drizzle, light rain, moderate rain, or heavy rain? This is forecasted in 12 hour blocks, and I take the sum of precipitation over that time frame to get a total [&hellip;]<\/p>\n","protected":false},"author":2,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[1],"tags":[],"class_list":["post-802","post","type-post","status-publish","format-standard","hentry","category-uncategorized","post-preview"],"_links":{"self":[{"href":"https:\/\/www.starcoder.com\/wordpress\/wp-json\/wp\/v2\/posts\/802","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.starcoder.com\/wordpress\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.starcoder.com\/wordpress\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.starcoder.com\/wordpress\/wp-json\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/www.starcoder.com\/wordpress\/wp-json\/wp\/v2\/comments?post=802"}],"version-history":[{"count":1,"href":"https:\/\/www.starcoder.com\/wordpress\/wp-json\/wp\/v2\/posts\/802\/revisions"}],"predecessor-version":[{"id":803,"href":"https:\/\/www.starcoder.com\/wordpress\/wp-json\/wp\/v2\/posts\/802\/revisions\/803"}],"wp:attachment":[{"href":"https:\/\/www.starcoder.com\/wordpress\/wp-json\/wp\/v2\/media?parent=802"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.starcoder.com\/wordpress\/wp-json\/wp\/v2\/categories?post=802"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.starcoder.com\/wordpress\/wp-json\/wp\/v2\/tags?post=802"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}