Unix timestamps, 180 m wind, DNI and a sneak peak geocoding API

New features at Open-Meteo

Jul 4, 2022

A couple of cool new features are available at Open-Meteo now:

Unix timestamps:

Unix timestamps can now be selected instead of ISO8601 timestamps. Numeric unix timestamps in seconds after January 1st 1970 make is easier for some applications to work with time and date functions.

Per default the API will use ISO8601 timestamps like 2022-07-01T18:00 which are more human friendly to read.

If you select a timezone, Open-Meteo APIs will align to 0:00 local time. The default API behaviour with ISO8601 time format, also all data now at ...T00:00 local time. This is convenient to just select a location with a timezone, and your app always has data starting at exactly 0:00 local time.

Unfortunately there is a catch with unix-timestamps: In case of Berlin 0:00 in European summer time, it is be 22:00 UTC time (2 hours earlier but now the previous UTC day). Because unix-timestamps are strictly UTC time, also the API will return timestamps starting at 22:00 UTC time. To correctly show the time now to users, the utc_offset_seconds value needs to be added: 22:00 UTC-time + 2 hours offset => 0:00 local-time. This also has to be done for daily values. Here you could easily overlook that the utc_offset_seconds also has to be applied again. If forgotten, the result is that your daily data are shifted by one day!

Still I highly recommend unix timestamps. If implemented correctly, they make working with data more easier. At Open-Meteo unix timestamps are used internally for calculations. Additionally, I noticed that Open-Meteo APIs perform a bit faster, because less string and date time operations are required ;-)

180 m wind

Wind speeds at 180 m elevation about ground are now available as well. I wrote a small summary with some graphs:

open-meteo

Wind forecasts at 180 m altitude

Wind forecasts at 180 m above ground are now available in Open-Meteo APIs and can be used free of charge for non-commercial use! Typically wind speeds at higher altitude tend to be stronger. This can be approximated by the wind profile power law. Open-Meteo uses weather models which calculate wind speeds at…

a year ago · open-meteo

Direct Normal Irradiance (DNI)

DNI is now available along with corrected solar radiation forecasts:

open-meteo

Improved solar radiation forecast

Forecasts for solar irradiance just got a bit more accurate and easier to use for photovoltaic energy predictions. Direct and diffuse solar radiation are now using clear sky models to preserve the correct daytime curvature even after 4 or more days of forecast. Previously, after 4 days of weather forecast, the daily maximum of solar radiation was a bit o…

a year ago · open-meteo

Sneak peak: Geocoding API

In the last couple of weeks I was focusing on a Geocoding API to enable users to search for city names and quickly get geographical coordinates. This is a great addition in using Open-Meteo APIs, because soon weather forecast APIs can be used with location names instead of just WGS84 coordinates. The first version is now available and working reliable, but not all features are implemented:

Simple search for city names ✅
Full language support ✅
Postal code search ✅ (not yet all postcodes available)
Intelligent ranking algorithm to prioritise important cities ✅
GeoIP support ❌
Proximity search ❌
Country filter ❌
Client SDK ❌
Integration into weather forecast API ❌

The missing features will be added in the next weeks and a proper release announcement will follow.

Last bug not least: The Geocoding API source code will also be release on Github soon!

You can already try the new Geocoding API! An easy URL configurator is available here: https://open-meteo.com/en/docs/geocoding-api