{"id":3082,"date":"2020-02-03T14:55:23","date_gmt":"2020-02-03T14:55:23","guid":{"rendered":"https:\/\/www.weatherimpact.com\/?p=3082"},"modified":"2020-02-20T15:11:27","modified_gmt":"2020-02-20T15:11:27","slug":"quality-of-our-forecasts","status":"publish","type":"post","link":"https:\/\/www.weatherimpact.com\/quality-of-our-forecasts\/","title":{"rendered":"Quality of our forecasts &#8211; how we add value"},"content":{"rendered":"<p>Weather works differently near the equator. African rainstorms are very erratic, develop fast and on a small scale. It is therefore important to use models and algorithms that can predict these weather patterns. Weather Impacts\u2019 high-quality forecasts are based on three sources of data: (1) the ensemble prediction system of the European Centre for Medium-range Weather Forecasting (ECMWF), which is considered the best global weather model, (2) local weather stations, (3) high quality satellite observations. <!--more-->These data sources allow us to deliver highly reliable weather forecasts for every location, no matter how remote. With clever algorithms we integrate knowledge from our data sources into forecasts that are tailored towards user needs, and thereby provide farmers and agribusiness with the information they need, at the right time.<\/p>\n<p>&nbsp;<\/p>\n<ul>\n<li><strong> High spatial resolution (9 km)<\/strong><\/li>\n<li><strong> Precipitation probability 80% accurate for 1 week ahead*<\/strong><\/li>\n<li><strong> Available in every local language<\/strong><\/li>\n<li><strong> Based on best quality weather models, state of the art satellite data, WMO validated ground stations and crowd sourced rain observations<\/strong><\/li>\n<\/ul>\n<p>*70-90% depending on the location, based on more then 100 WMO validated weather stations in Africa.<\/p>\n<h2><span style=\"color: #ef9439;\"><b>Our forecasts are based on three data sources which allow us to deliver highly reliable weather forecasts for every location, no matter how remote<\/b><\/span><\/h2>\n<p>&nbsp;<\/p>\n<h2><span style=\"color: #3498db;\">Our forecast vs regular weather models<\/span><\/h2>\n<p><img decoding=\"async\" class=\"alignnone size-medium wp-image-3118\" src=\"https:\/\/www.weatherimpact.com\/wp-content\/uploads\/2020\/02\/comparison_ecmwf_gfs-Python-300x209.png\" alt=\"\" width=\"300\" height=\"209\" srcset=\"https:\/\/www.weatherimpact.com\/wp-content\/uploads\/2020\/02\/comparison_ecmwf_gfs-Python-300x209.png 300w, https:\/\/www.weatherimpact.com\/wp-content\/uploads\/2020\/02\/comparison_ecmwf_gfs-Python-768x536.png 768w, https:\/\/www.weatherimpact.com\/wp-content\/uploads\/2020\/02\/comparison_ecmwf_gfs-Python.png 892w\" sizes=\"(max-width: 300px) 100vw, 300px\" \/><\/p>\n<p>The graph above shows a comparison between data from the Global Forecasting System\u00a0Model (GFS) from the National Centre for Environmental Prediction (NCEP),\u00a0on which a lot of\u00a0free<br \/>\navailable weather forecasts are based, and the European Centre for Medium Range Weather Forecasting (ECMWF) on which the forecasts of Weather Impact are based. The comparison is made using the Equitable Threat Score with data\u00a0from the World Meteorological Organization (WMO), see also <a href=\"https:\/\/apps.ecmwf.int\/wmolcdnv\/\">https:\/\/apps.ecmwf.int\/wmolcdnv\/<\/a>.\u00a0The\u00a0Equitable Threat Score\u00a0(ETS) measures the skill of a forecast relative to chance and is often used in the verification of precipitation forecasts.<\/p>\n<p>The images below shows the difference in spatial resolution over Kenya between GFS and ECMWF.<\/p>\n<p><img decoding=\"async\" class=\"alignnone size-medium wp-image-3039\" src=\"https:\/\/www.weatherimpact.com\/wp-content\/uploads\/2020\/02\/Kenya-GFS-245x300.png\" alt=\"\" width=\"245\" height=\"300\" srcset=\"https:\/\/www.weatherimpact.com\/wp-content\/uploads\/2020\/02\/Kenya-GFS-245x300.png 245w, https:\/\/www.weatherimpact.com\/wp-content\/uploads\/2020\/02\/Kenya-GFS.png 680w\" sizes=\"(max-width: 245px) 100vw, 245px\" \/>\u00a0 \u00a0 \u00a0 <img decoding=\"async\" class=\"alignnone size-medium wp-image-3038\" src=\"https:\/\/www.weatherimpact.com\/wp-content\/uploads\/2020\/02\/Kenya-ECMWF-244x300.png\" alt=\"\" width=\"244\" height=\"300\" srcset=\"https:\/\/www.weatherimpact.com\/wp-content\/uploads\/2020\/02\/Kenya-ECMWF-244x300.png 244w, https:\/\/www.weatherimpact.com\/wp-content\/uploads\/2020\/02\/Kenya-ECMWF.png 681w\" sizes=\"(max-width: 244px) 100vw, 244px\" \/><\/p>\n<p>We evaluate\u00a0the performance of our forecasts\u00a0in collaboration with National Meteorological Agencies\u00a0of various African countries. This collaboration enables us to compare\u00a0our\u00a0forecasts\u00a0to\u00a0historical archives of\u00a0weather\u00a0stations\u00a0that are validated by the World Meteorological\u00a0Organization\u00a0(WMO).<\/p>\n<p>Because we use ground station data in a multi-year analysis, the results of our validation are robust under seasonal variability. Furthermore, it is excluded from\u00a0biases that\u00a0are\u00a0introduced when remote sensing or satellite data is used as a reference.\u00a0Our\u00a0forecast evaluation studies follow scientific international standards for validating weather forecasts.<\/p>\n<p>International standards on which our work is based:<\/p>\n<ul>\n<li>\u201cRecommendations on the verification of local weather forecasts\u201d, ECMWF Technical Memoranda, Pertti Nurmi, 2003<\/li>\n<li>Guide to Agricultural Meteorological Practices (GAMP), 2010 Edition (WMO-No.134), Updated in 2012<\/li>\n<\/ul>\n<h2><span style=\"color: #3498db;\">Farmer evaluations<\/span><\/h2>\n<p>The usefulness and accuracy of forecasts for end-users are evaluated by our local partners via interviews and farmer testimonials.<br \/>\nThe rainfall forecasts are rated as useful and of high quality:<\/p>\n<p><b>10<\/b><b>0% of the farm<\/b><b>ers evaluate our rainfall forecast as useful.<br \/>\n<\/b><b><\/b><b>96% of the farmers evaluate our forecast as very accurate or close to accurate.<\/b><\/p>\n<p>&nbsp;<\/p>\n<h3 style=\"text-align: center;\"><span style=\"color: #ef9439;\"><i>\u201cOur farmers mention that this\u00a0weather <\/i><\/span><\/h3>\n<h3 style=\"text-align: center;\"><span style=\"color: #ef9439;\"><i>forecast is more reliable\u00a0than what they <\/i><\/span><\/h3>\n<h3 style=\"text-align: center;\"><span style=\"color: #ef9439;\"><i>receive from other media sources.\u201d\u200b<\/i><\/span><\/h3>\n<p>&nbsp;<\/p>\n","protected":false},"excerpt":{"rendered":"<p>Weather works differently near the equator. African rainstorms are very erratic, develop fast and on a small scale. It is therefore important to use models and algorithms that can predict these weather patterns. Weather Impacts\u2019 high-quality forecasts are based on three sources of data: (1) the ensemble prediction system of the European Centre for Medium-range [&hellip;]<\/p>\n","protected":false},"author":5,"featured_media":3080,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[1],"tags":[],"acf":[],"_links":{"self":[{"href":"https:\/\/www.weatherimpact.com\/wp-json\/wp\/v2\/posts\/3082"}],"collection":[{"href":"https:\/\/www.weatherimpact.com\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.weatherimpact.com\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.weatherimpact.com\/wp-json\/wp\/v2\/users\/5"}],"replies":[{"embeddable":true,"href":"https:\/\/www.weatherimpact.com\/wp-json\/wp\/v2\/comments?post=3082"}],"version-history":[{"count":0,"href":"https:\/\/www.weatherimpact.com\/wp-json\/wp\/v2\/posts\/3082\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.weatherimpact.com\/wp-json\/wp\/v2\/media\/3080"}],"wp:attachment":[{"href":"https:\/\/www.weatherimpact.com\/wp-json\/wp\/v2\/media?parent=3082"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.weatherimpact.com\/wp-json\/wp\/v2\/categories?post=3082"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.weatherimpact.com\/wp-json\/wp\/v2\/tags?post=3082"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}