Get Hourly/Daily Weather from KNMI Through Open-Meteo

Source: R/weather.R

Retrieves hourly weather data from the Open-Meteo API using the KNMI HARMONIE AROME weather model via the /v1/forecast endpoint. The KNMI model provides high-resolution forecasts (2 km for the Netherlands, 5.5 km for Europe) updated hourly. The "knmi_seamless" model (default) blends KNMI HARMONIE AROME with ECMWF IFS beyond the 2.5-day KNMI horizon.

get_weather_hourly(
  latitude = 53.22,
  longitude = 6.57,
  metrics = "temperature_2m",
  past_days = 30,
  forecast_days = 0,
  model = "knmi_seamless",
  timezone = "Europe/Amsterdam",
  api_url = "https://api.open-meteo.com/v1/forecast"
)

get_weather_daily(min_hour = 8, max_hour = 17, fun = base::mean, ...)

Arguments

latitude

Latitude in decimal degrees (WGS84). Default: 53.22 (Groningen). Use negative values for the Southern Hemisphere.

longitude

Longitude in decimal degrees (WGS84). Default: 6.57 (Groningen). Use negative values for locations west of Greenwich.

metrics

Character vector of one or more hourly weather metrics to retrieve (default: "temperature_2m"). Multiple metrics can be specified, e.g. c("temperature_2m", "wind_speed_10m"). Common metrics include:

  • "temperature_2m": air temperature at 2 m above ground (degrees Celsius)

  • "relative_humidity_2m": relative humidity at 2 m (%)

  • "precipitation": rain + snow total (mm)

  • "wind_speed_10m": wind speed at 10 m (km/h)

  • "cloud_cover": total cloud cover (%)

See the KNMI API documentation for the full list of available variables.

past_days

Integer number of past days to include (default: 30, range: 0–92).

forecast_days

Integer number of forecast days to include (default: 0, range: 0–16). The native KNMI model provides up to 2.5 days; beyond that, the seamless model falls back to ECMWF IFS.

model

Character string specifying the weather model. One of "knmi_seamless" (default, KNMI + ECMWF blend), "knmi_harmonie_arome_europe" (5.5 km, Central & Northern Europe), or "knmi_harmonie_arome_netherlands" (2 km, Netherlands & Belgium).

timezone

Character string for the timezone of returned timestamps (default: "Europe/Amsterdam").

api_url

Base URL of the Open-Meteo API endpoint.

min_hour

First hour of the day to include on a 0-23 scale. Default: 8.

max_hour

Last hour of the day to include on a 0-23 scale. Default: 17.

fun

Function to use for calculation, defaults to mean().

...

Arguments passed on to get_weather_hourly().

Value

A data.frame with columns:

  • time: POSIXct timestamp in the requested timezone

  • One column per requested weather variable, named as given in metrics

Examples

if (FALSE) { # \dontrun{
# temperature in Groningen over the past 30 days
get_weather_hourly()
get_weather_daily() # default: between 08:00-17:59


assen <- geocode("Assen", as_coordinates = TRUE, crs = 4326)
latitude(assen)
longitude(assen)
get_weather_daily(latitude = latitude(assen),
                  longitude = longitude(assen))


# wind speed with 3-day forecast
get_weather_hourly(metrics = "wind_speed_10m", past_days = 7, forecast_days = 3)

# multiple variables at once
get_weather_hourly(metrics = c("temperature_2m", "relative_humidity_2m"))

# high-resolution Netherlands-only model
get_weather_hourly(model = "knmi_harmonie_arome_netherlands",
                   past_days = 0,
                   forecast_days = 2)
} # }