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Dec 12, 2018· 4 min, 1 sec

Need a Weather Underground Replacement? Switch to Tomorrow.io

Have you heard that the Weather Underground® API is being retired on December 31st, 2018?

That leaves precious little time to make changes to any applications that use it. Here’s the good news: Tomorrow.io is migrating WU API users for free, providing three months free on those plans. 

The Tomorrow.io® API has the historical, current, and forecasting capabilities that Weather Underground used to, plus more. You can not only replace what you had, you can get more accurate weather conditions, and you can even add functionality if you’d like!

If you’re using the Weather Underground API, it would be totally understandable for you to think your best path forward is to rip out weather information from your application, and live without it for a time. However, this is a great opportunity for you to replace what you have with something even better, and to think about adding new weather functionality.

One of the most exciting capabilities Tomorrow.io provides is the ability to receive proactive alerts for areas. Instead of polling to see if an area has had an alert, you can sign up to receive the information from us. That way, you don’t have to make many requests to the API, especially when it’s relatively rare to have an alert for a location. Think of the bandwidth you’ll save! We can directly message your users by email or text, or you can set up a webhook to receive the alerts centrally.

Another great feature of the Tomorrow.io API is that it provides weather map tile overlays. We provide weather graphics, like precipitation, that you can layer on top of maps, such as Google Maps. Then users can see not only where they are and where they want to go, but also what the weather is like! See our documentation for more information.

Benefits and Features of the Tomorrow.io API

  • Quick setup and a modern API (JSON & REST)
  • The most accurate weather data available 
  • Unique API endpoints for different use cases
  • Ground level weather (not 1,000m above our heads)
  • New & innovative technology
  • The only API that provides
    • 15 days of forecasting
    • Millions of virtual weather sensors for more accuracy and granularity
  • Read More about Tomorrow.io’s unique value propositions here

Steps to Use the Tomorrow.io API

  1. Sign up to Get an API Key
  2. Make API calls.

It couldn’t be much easier to get started with our API. Like many APIs, Tomorrow.io will allow you access when you provide your API Key as a header in your API request. Our API is RESTful and provides JSON content. Below are the API endpoints available to you.

Weather API Endpoints

  • Tiles: Get weather image overlays for maps
  • Nowcast: minute by minute data for the next 6 hours, based on our proprietary forecasting models
  • Hourly Forecast: hourly weather predictions for the next 4 ½ days
  • Daily Forecast: daily weather predictions for the next 15 days
  • Forecast: aggregated data with minute by minute data for the next 6 hours, then hourly and daily predictions up to 15 days forward
  • Realtime: current conditions
  • Historical: from 1977 onward

Administrative Endpoints

  • Locations: Manage locations you care about
  • Alerts: Receive alerts about weather events
  • Groups: Manage groups of users who receive alerts
  • Webhooks: Set up webhook alerts

If you’re coming from the Weather Underground API, the endpoints that are probably the most similar to the ones you’re using are the daily forecast, hourly forecast, and real time endpoints. Here’s an example of what you would do to get the hourly forecast from the Tomorrow.io API.

Hourly Forecast

GET https://api2.tomorrow.io/v2/weather/forecast/daily?lat=85.354&lon=33.231&fields=temp,precipitation


  • Content-type: application/json
  • apikey: your-unique-key

The biggest difference for you, dear API user, is that Weather Underground took cities as inputs for locations, and Tomorrow.io takes latitudes and longitudes as input. We’re certainly considering taking cities as input in the future, but for now, you can probably find a good library to do the city to lat/long translation for you, or get your users’ latitude and longitude from their location for the most accurate, relevant information.

Here are some resources you may be able to use to help with the conversion from city to lat/long:

We at Tomorrow.io hope you’ll consider using our API. We’re happy to provide free plans to developers who make fewer than 50K calls per month, and we’re dedicated to providing our developer community with the most accurate weather information. Please join us in marrying the weather industry with cutting edge technology!