meteo_ogimet_synop: Download and decode raw SYNOP messages from the Ogimet...

In climate: Interface to Download Meteorological (and Hydrological) Datasets

Download and decode raw SYNOP messages from the Ogimet getsynop service

Description

Downloads raw SYNOP messages from the Ogimet getsynop endpoint and decodes them into a tidy data.frame using the synop_parser() function. Two retrieval modes are supported:

Usage

meteo_ogimet_synop(
  station = NULL,
  date = c(Sys.Date() - 30, Sys.Date()),
  country = NULL,
  country_name = NULL,
  simplified = TRUE,
  allow_failure = TRUE
)

Arguments

station	Numeric or character vector of WMO station IDs. Optional when country_name is provided; required otherwise.
date	Character or Date vector of length 2 giving the start and end of the requested period, e.g. c("2009-12-01", "2009-12-04"). Defaults to the last 30 days.
country	Optional; passed to synop_parser() for country-specific precipitation indicator decoding (e.g. "RU"). Single string or NULL (default). This is distinct from country_name.
country_name	Optional character string naming the country whose stations should be downloaded, as recognised by Ogimet (e.g. "Poland", "Germany", "France"). When provided, the ⁠state=⁠ Ogimet parameter is used and station is ignored. The full date range is fetched in a single request.
simplified	Logical. When TRUE (default) returns a compact data.frame with 20 standardised columns (see Value below). When FALSE the full parser output is returned.
allow_failure	Logical. When TRUE (default) network errors are caught and a message is emitted; when FALSE errors propagate to the caller.

Details

• Station mode (station provided): fetches messages for one or more WMO station IDs. URL form: ⁠http://www.ogimet.com/cgi-bin/getsynop?block=<id>&begin=<YYYYMMDDhhmm>&end=<YYYYMMDDhhmm>⁠

• Country mode (country_name provided): fetches messages for all Ogimet stations in a country in a single request. URL form: ⁠http://www.ogimet.com/cgi-bin/getsynop?begin=<YYYYMMDDhhmm>&end=<YYYYMMDDhhmm>&state=<country_name>⁠

When both station and country_name are supplied, country_name takes precedence and a warning is issued.

Each line of the response is a comma-separated record: ⁠station_id,year,month,day,hour,minute,<SYNOP message>⁠. The SYNOP message is decoded via synop_parser() with as_data_frame = TRUE.

Value

By default (simplified = TRUE), a compact data.frame with one row per decoded SYNOP observation. Columns:

• date — Observation date-time (POSIXct, UTC).

• station — WMO station identifier (character).

• t2m — Air temperature at 2 m (°C).

• dpt2m — Dew-point temperature at 2 m (°C).

• rel_hum — Relative humidity (%), derived via compute_relative_humidity().

• tmax — Daily maximum temperature from Section 3 (°C).

• tmin — Daily minimum temperature from Section 3 (°C).

• wd — Wind direction (degrees).

• ws — Wind speed (m/s or knots, per wind_unit).

• gust — Highest gust speed from Section 3, same unit as ws.

• press — Station-level pressure (hPa).

• slp — Sea-level pressure (hPa).

• press_tend — 3-hour pressure change (hPa).

• precip — Precipitation amount (mm).

• Nt — Total cloud cover (oktas, 0–8) from the Nddff group.

• Nh — Cover of low clouds (genera Sc, St, Cu, Cb) in oktas (0–8), from Section 1 group ⁠8NhCLCMCH⁠; NA when not reported.

• N_base — Height of base of lowest observed cloud (m).

• insol — Daily sunshine duration (hours).

• visibility — Horizontal visibility (m).

• snow — Total snow depth (cm); 0 for trace amounts.

When simplified = FALSE, a data.frame with the first two columns station_id (WMO identifier, character) and Date (POSIXct, UTC), followed by all columns produced by synop_parser() with as_data_frame = TRUE: station_type, region, obs_day, obs_hour, wind_unit, wind_estimated, visibility, cloud_cover, wind_direction, wind_speed, air_temperature, dewpoint_temperature, station_pressure, sea_level_pressure, pressure_tendency, pressure_change, precipitation_amount, precipitation_time, cloud_base_min, cloud_base_max, low_cloud_type, middle_cloud_type, high_cloud_type, low_cloud_amount, maximum_temperature, minimum_temperature, gust, sunshine_duration, snow_depth, snow_depth_state, source.

Returns NULL invisibly when the download fails and allow_failure = TRUE.

Examples

  # Station mode: Poznan-Lawica (Poland)
  poznan = meteo_ogimet_synop(station = 12330,
                              date = c("2009-12-01", "2009-12-04"))
  head(poznan)

  # Station mode: multiple stations
  two_stations = meteo_ogimet_synop(station = c(12330, 12375),
                                    date = c("2019-06-01", "2019-06-03"))
  head(two_stations)
  
  # Country mode: all Polish stations for one day
  poland = meteo_ogimet_synop(country_name = "Poland",
                              date = c("2009-12-15", "2009-12-15"))
  head(poland)

  # Simplified view
  poznan_simple = meteo_ogimet_synop(station = 12330,
                                     date = c("2009-12-01", "2009-12-04"),
                                     simplified = TRUE)
  head(poznan_simple)

climate documentation built on Sept. 18, 2026, 5:06 p.m.