Open-Meteo Archive

Open-Meteo Archive provides global historical weather data from the ERA5 reanalysis dataset (1940–present) at ~25 km resolution. No API key is required.

MetaData(OpenMeteoArchive())

MetaData("", "10,000 calls/day (non-commercial)", :weather, Dict(:temperature_2m_mean => "Daily mean temperature at 2m (°C)", :wind_direction_10m_dominant => "Daily dominant wind direction (°)", :apparent_temperature_max => "Daily maximum apparent temperature (°C)", :surface_pressure => "Surface pressure (hPa)", :precipitation_sum => "Daily total precipitation (mm)", :wind_gusts_10m_max => "Daily maximum wind gusts at 10m (km/h)", :precipitation_hours => "Daily hours with precipitation", :temperature_2m => "Air temperature at 2m (°C)", :rain_sum => "Daily total rain (mm)", :wind_direction_10m => "Wind direction at 10m (°)"…), :raster, "25 km", "Global", :timeseries, Hour(1), "1940-present", "CC BY 4.0", "https://open-meteo.com/en/docs/historical-weather-api", Dict("DataFrames" => "a93c6f00-e57d-5684-b7b6-d8193f3e46c0"))

Hourly Data

plan = DataAccessPlan(OpenMeteoArchive(), (-74.0, 40.7),
    Date(2024, 1, 1), Date(2024, 1, 3);
    variables = [:temperature_2m, :precipitation],
    frequency = :hourly)

DataAccessPlan for openmeteoarchive
  Extent:    Point(40.7, -74.0)
  Time:      2024-01-01 to 2024-01-03 (3 days)
  Variables: temperature_2m, precipitation
  frequency: hourly
  timezone: GMT
  API calls: 1
  Est. size: 1.125 KiB

  Request 1: GET 1 point(s), hourly 3 days → openmeteoarchive/8ffb4df0acfa8b3.json

files = fetch(plan)
data = JSON.parsefile(files[1])
keys(data)

KeySet for a JSON.Object{String, Any} with 9 entries. Keys:
  "latitude"
  "longitude"
  "generationtime_ms"
  "utc_offset_seconds"
  "timezone"
  "timezone_abbreviation"
  "elevation"
  "hourly_units"
  "hourly"

Daily Data

Daily aggregates use different variable names (e.g. temperature_2m_max instead of temperature_2m):

files = fetch(OpenMeteoArchive(), (-74.0, 40.7),
    Date(2024, 1, 1), Date(2024, 1, 7);
    variables = [:temperature_2m_max, :temperature_2m_min, :precipitation_sum],
    frequency = :daily)

data = JSON.parsefile(files[1])
keys(data)

KeySet for a JSON.Object{String, Any} with 9 entries. Keys:
  "latitude"
  "longitude"
  "generationtime_ms"
  "utc_offset_seconds"
  "timezone"
  "timezone_abbreviation"
  "elevation"
  "daily_units"
  "daily"

Variables

Hourly

Variable	Description
temperature_2m	Air temperature at 2m (°C)
relative_humidity_2m	Relative humidity at 2m (%)
dew_point_2m	Dew point at 2m (°C)
apparent_temperature	Apparent (feels-like) temperature (°C)
precipitation	Total precipitation (mm)
rain	Rain (mm)
snowfall	Snowfall (cm)
snow_depth	Snow depth (m)
pressure_msl	Mean sea level pressure (hPa)
surface_pressure	Surface pressure (hPa)
cloud_cover	Total cloud cover (%)
wind_speed_10m	Wind speed at 10m (km/h)
wind_direction_10m	Wind direction at 10m (°)
wind_gusts_10m	Wind gusts at 10m (km/h)
shortwave_radiation	Shortwave radiation (W/m²)
weather_code	WMO weather code
et0_fao_evapotranspiration	Reference evapotranspiration (mm)
soil_temperature_0_to_7cm	Soil temperature 0-7cm (°C)
soil_moisture_0_to_7cm	Soil moisture 0-7cm (m³/m³)

Daily

Variable	Description
temperature_2m_max	Daily maximum temperature at 2m (°C)
temperature_2m_min	Daily minimum temperature at 2m (°C)
temperature_2m_mean	Daily mean temperature at 2m (°C)
apparent_temperature_max	Daily maximum apparent temperature (°C)
apparent_temperature_min	Daily minimum apparent temperature (°C)
precipitation_sum	Daily total precipitation (mm)
rain_sum	Daily total rain (mm)
snowfall_sum	Daily total snowfall (cm)
wind_speed_10m_max	Daily maximum wind speed at 10m (km/h)
wind_gusts_10m_max	Daily maximum wind gusts at 10m (km/h)
wind_direction_10m_dominant	Daily dominant wind direction (°)
precipitation_hours	Daily hours with precipitation
sunrise	Sunrise time (ISO8601)
sunset	Sunset time (ISO8601)
sunshine_duration	Sunshine duration (s)
shortwave_radiation_sum	Daily total shortwave radiation (MJ/m²)