CustomWeather
CustomWeather is a Mill Valley, California-based weather data company founded in 2000 by Geoff Flint, its president and chief executive, that supplies forecasts, real-time observations, severe weather alerts and historical weather data to media companies, utilities, government bodies and businesses in more than two hundred countries. Unlike consumer weather brands, CustomWeather works mainly behind the scenes: its data appear inside other companies' websites, applications, broadcasts and business systems, delivered through application programming interfaces and customized feeds. The company was among the first weather firms to launch a weather data API, in 2002, and to build an OpenGIS-based map server for weather data, in 2003. It has deliberately remained small, presenting boutique-level, customized service as its advantage, while maintaining data for millions of locations in more than eighty-five languages and a historical archive extending back more than fifty years.
Founding in 2000
CustomWeather was established in 2000, at the moment when businesses were beginning to treat web-delivered data as a product in itself. Geoff Flint founded the company and has remained its president and chief executive throughout its history, giving it unusual leadership continuity for a technology firm of its age. The company is headquartered in Mill Valley, in the San Francisco Bay Area, and when it marked its twentieth anniversary in 2020 it described itself as having grown from a provider of global forecasts for businesses into a weather technology innovator, developing first-of-its-kind products that give clients precision data for their own customers or for integration into their internal systems.
That anniversary framing is consistent with the company's record. CustomWeather's early moves were not about building a consumer destination to compete with the big weather websites, although it does operate the consumer forecast site MyForecast.com. Its defining decisions were about delivery: making weather available as structured, geo-coded data that other systems could request automatically, at a time when most weather content was still published as finished pages and maps for humans to read.
Geo-Coded Data and the Wireless Era
CustomWeather's earliest distinction was location. The company geo-coded its products so that weather could be delivered based on GPS coordinates, postal codes or city names, for domestic and international locations, and it described its forecasts at the time as the only weather data available through web-based XML queries. In 2001 it launched a geo-coded severe weather alerts service that delivered United States National Weather Service warnings, watches, advisories and statements as a real-time, geo-coded XML feed covering more than 26,000 locations in the United States and Puerto Rico. Flint emphasized that the company was not merely retransmitting alerts, but formatting them so clients could filter them by precise geography and user group and route them to wireless and web services, including SMS.
The wireless context dates these products but also explains them. In the early 2000s, mobile carriers and travel companies were racing to put location-based content on phones, and CustomWeather built WAP-compatible weather services offering current conditions, seven-day forecasts, airport delay forecasts, tide tables, earthquake reports, hurricane tracking and severe weather alerts in multiple languages and in both imperial and metric units. Travel distribution company Galileo International deployed CustomWeather data so that travel agencies and travelers using its Viewpoint and wireless products could receive forecast information tied to their travel plans. The pattern, weather as an ingredient inside another company's service, has remained the company's business model ever since.
The Weather API, Launched in 2002
In early 2002 CustomWeather became one of the first weather companies to launch a weather data API, having begun development in 2001 as demand grew for serving weather through a web interface. The retrospective the company published for its twentieth anniversary stressed how new the concept was: requesting weather data instantaneously over HTTP for any location on earth, and specifically requesting it by coordinates rather than by a fixed list of city codes, were breakthroughs at the time. Application programming interfaces have since become the default way businesses consume data of every kind, and weather APIs are now a crowded market, which makes CustomWeather's early entry a genuine part of the industry's history.
The API remains a core product. Its data are available in XML or JSON formats over secure HTTPS connections, with geo-lookup by coordinates, hyperlocal data for more than 80,000 locations, satellite, radar and future radar animations through a map tile server, content in more than eighty-five languages, and the ability to refine forecasts down to one hundred metre resolution worldwide, according to the company's anniversary description. The company noted that its API saw renewed growth when the popular Dark Sky API, used by many application developers, was discontinued, sending developers looking for established alternatives.
The OpenGIS Map Server and Mapping Products
In March 2002 CustomWeather also began developing what it describes as the first OpenGIS-based map server for weather data, launched in 2003 after close work with the Open Geospatial Consortium. The server let customers overlay CustomWeather's weather image layers onto their own layers or base maps using open standards, rather than receiving a finished map image they could not manipulate. For utilities, media companies and government users who already worked with geographic information systems, that interoperability mattered: weather could be combined with their own assets, territories and infrastructure on a single map. The company has continued to offer geographic information system products built around that philosophy, treating weather as one layer in a customer's spatial data rather than as a standalone picture.
Products and Data Coverage
CustomWeather's catalogue covers the three time horizons its clients need. Historical data support analysis and model training; the company maintains an archive it describes as dating back more than fifty years, and its climate offerings have aggregated daily values across more than 85,000 global forecast locations with records reaching back to 1980, enriched with thirty-year climatological averages at hourly and daily resolutions. Real-time data provide current conditions and observations. Forecast data range from hyperlocal short-term forecasts to extended products such as the day-by-day thirty-day forecast for syndication the company introduced in 2023, aimed at business planning in weather-sensitive industries.
Recent product development shows the same processing philosophy applied to modern public data. CustomWeather integrated the Multi-Radar Multi-Sensor system, known as MRMS, from the National Oceanic and Atmospheric Administration's National Severe Storms Laboratory into its Cloud Weather Services API, delivering precipitation data at one kilometre spatial resolution. The company noted that MRMS data are publicly available but distributed in complex formats that limit their use, and that its contribution is a managed pipeline that ingests, processes and validates the data and delivers it in developer-friendly forms, including JSON and XML for point queries and netCDF for gridded data, with Kevin Levey, its vice president of operations, presenting the work as removing that barrier for clients.
Daily Reports and Subscription Services
Alongside its enterprise feeds, CustomWeather has productized simpler offers for smaller weather-sensitive businesses. In May 2025 it launched an online subscription for customized daily weather reports, aimed at the construction, energy, outdoor venue, agriculture and marine sectors. Subscribers choose a precise location by city name or coordinates, select standard or marine-specific reports, set how many updates per day they want and when, and receive forecasts as PDF files by email or, for American customers, by MMS. Flint explained that the goal was an easy and affordable way for businesses to receive consistent daily information for planning, worker safety and resource deployment, opening services the company had provided to large clients for twenty-five years to customers who could subscribe online without a custom contract.
Clients and Sectors
CustomWeather identifies its core client groups as utilities, media, business and government institutions. For media companies, its forecasts and maps appear under the client's own brand, a classic syndication arrangement in which the audience may never see the CustomWeather name. For utilities and energy companies, granular forecasts and alerts inform operations and safety decisions. For government and enterprise clients, historical and real-time data feed planning, analytics and, increasingly, internal artificial intelligence models, a use the company explicitly cites for its historical archive. Its global scope is a recurring theme: forecasts for more than two hundred countries, data for millions of locations, and content in up to ninety-five languages in some company descriptions.
A Small Company by Design
One of CustomWeather's most distinctive positions is its size. The company states that it has maintained a small size deliberately, in order to offer exclusive, customized solutions with boutique-level customer service and support. In an industry that includes global data giants and venture-funded platforms competing on scale, CustomWeather competes on responsiveness and customization, building to a client's specification rather than selling only a standard feed. Its longevity, twenty-five years of operation celebrated in its 2025 product announcements, suggests that the niche is durable: there is a persistent market of organizations whose weather needs are too specific for a commodity application, but who do not want to build a meteorology department of their own.
Why CustomWeather Matters
CustomWeather matters less as a household name than as infrastructure. It helped define how weather data are sold and delivered in the internet era, among the first to offer a weather API, geo-coded alerts and standards-based map layers, and it has carried that data-broker role from the WAP phones of 2001 to today's cloud APIs and climate analytics. For a directory of media agencies, its relevance is direct: a share of the forecasts audiences read on media and travel services originates with suppliers like CustomWeather, working invisibly behind the brands readers trust. Based in Mill Valley and still led by its founder, it remains a specialist wholesaler of one of the oldest kinds of news there is, the weather, in the modern form of data.
