Title: Fast Decoding of SYNOP (Surface Synoptic Observations) Meteorological Messages
Version: 1.0.0
Description: Decode raw SYNOP (surface synoptic observations) messages into data frames, extracting data from Sections 0, 1, and 3, including temperature, dew point, pressure, wind, clouds, and precipitation. Available functions to download SYNOP messages from Ogimet https://www.ogimet.com/ if needed. The decoding logic follows the specifications defined in the World Meteorological Organization (2019) "Manual on Codes, Volume I.1 (WMO-No. 306)".
License: MIT + file LICENSE
Encoding: UTF-8
RoxygenNote: 7.3.3
Depends: R (≥ 4.1.0)
Suggests: tibble, knitr, rmarkdown, testthat (≥ 3.0.0)
URL: https://ezequiel1593.github.io/synopR/
BugReports: https://github.com/ezequiel1593/synopR/issues
VignetteBuilder: knitr
NeedsCompilation: no
Packaged: 2026-04-03 21:32:32 UTC; eleze
Author: Ezequiel Elias [aut, cre]
Maintainer: Ezequiel Elias <elezeru15@gmail.com>
Repository: CRAN
Date/Publication: 2026-04-03 21:50:02 UTC

Check SYNOP messages for structural integrity

Description

Validates if SYNOP strings meet basic structural requirements, considering section indicators and 5-digit data groups.

Usage

check_synop(data)

Arguments

data

A character vector of SYNOP strings or the exact data frame returned by parse_ogimet().

Value

A data frame with validation results for each message.

Examples

msg <- paste0("AAXX 01123 87736 32965 13205 10214 20143 ",
              "30022 40113 5//// 80005 333 10236 20128=")
checked_synops <- check_synop(msg)

Direct download of meteorological data from Ogimet

Description

Direct download of meteorological data from Ogimet

Usage

direct_download_from_ogimet(wmo_identifier, initial_date, final_date)

Arguments

wmo_identifier

A 5-digit character string or integer representing the station WMO ID.

initial_date

Initial date, format "YYYY-MM-DD".

final_date

Final date, format "YYYY-MM-DD".

Details

The requested period cannot exceed 370 days. All queries assume UTC time zone. The returned data frame covers from 00:00 UTC of the initial_date to 23:00 UTC of the final_date, inclusive. Too many requests may trigger temporal blocks.

If the station identifier starts with 0 (zero), then wmo_identifier must be a string (e.g., "06447").

Value

A data frame, as returned by show_synop_data()

Examples

## Not run: 
direct_download_from_ogimet(wmo_identifier = '87585',
                            initial_date = "2024-01-10",
                            final_date = "2024-01-11")

## End(Not run)

Download SYNOP messages from Ogimet

Description

Download SYNOP messages from Ogimet

Usage

download_from_ogimet(wmo_identifier, initial_date, final_date)

Arguments

wmo_identifier

A 5-digit character string or integer representing the station WMO ID.

initial_date

Initial date, format "YYYY-MM-DD".

final_date

Final date, format "YYYY-MM-DD".

Details

The requested period cannot exceed 370 days. All queries assume UTC time zone. The returned dataset covers from 00:00 UTC of the initial_date to 23:00 UTC of the final_date, inclusive. Too many requests may trigger temporal blocks.

If the station identifier starts with 0 (zero), then wmo_identifier must be a string (e.g., "06447").

Value

A character vector with SYNOP strings.

Examples

## Not run: 
download_from_ogimet(wmo_identifier = '87585',
                    initial_date = "2024-01-10",
                    final_date = "2024-01-11")

## End(Not run)

Parse SYNOP strings downloaded from Ogimet into a data frame

Description

Parse SYNOP strings downloaded from Ogimet into a data frame

Usage

parse_ogimet(ogimet_data)

Arguments

ogimet_data

A character vector of Ogimet-format SYNOP strings.

Value

A data frame with Year, Month, Day, Hour, and Raw_synop.

Examples

msg <- paste0("87736,2026,01,01,12,00,AAXX 01123 87736 32965 13205 10214 20143 ",
              "30022 40113 5//// 80005 333 10236 20128=")
parsed_data <- parse_ogimet(msg)

Decode multiple SYNOP messages

Description

This function decodes a vector or data frame column of SYNOP strings belonging to the same or different meteorological surface station.

Usage

show_synop_data(data, wmo_identifier = NULL, remove_empty_cols = TRUE)

Arguments

data

A character vector, a data frame column containing raw SYNOP strings, or the exact data frame returned by parse_ogimet().

wmo_identifier

A 5-digit character string or integer representing the station WMO ID. If NULL (default), all messages are decoded.

remove_empty_cols

Logical. Should columns containing only NA values be removed? Default is TRUE.

Value

A data frame where each row represents one observation time and each column a decoded meteorological variable.

  1. wmo_id - WMO station identifier

  2. Year - (from parse_ogimet())

  3. Day - As informed by Section 0

  4. Hour - As informed by Section 0

  5. Cloud_base_height - Lowest cloud base height, in intervals

  6. Visibility - In meters

  7. Total_cloud_cover - In oktas, 9 means 'invisible' sky by fog or other phenomenon

  8. Wind_direction - In tens of degree, 99 means 'variable wind direction'

  9. Wind_speed

  10. Wind_speed_unit - Either 'm/s' or 'knots'

  11. Air_temperature - In degrees Celsius

  12. Dew_point - In degrees Celsius

  13. Relative_humidity - As a percentage

  14. Station_pressure - In hPa

  15. MSLP_GH - Mean sea level pressure (in hPa) or geopotential height (in gpm)

  16. Pressure_tendency - In hPa

  17. Charac_pressure_tend - String, simplified decoding

  18. Precipitation_S1 - In mm

  19. Precip_period_S1 - In hours ('Precipitation_S1' fell in the last 'Precip_period_S1' hours)

  20. Present_weather - String, simplified decoding

  21. Past_weather1 - String, simplified decoding

  22. Past_weather2 - String, simplified decoding

  23. Cloud_amount_Nh - Cloud coverage from low or medium cloud, same as 'Total_cloud_cover'

  24. Low_clouds_CL - String, simplified decoding

  25. Medium_clouds_CM - String, simplified decoding

  26. High_clouds_CH - String, simplified decoding

  27. Max_temperature - In degrees Celsius

  28. Min_temperature - In degrees Celsius

  29. Ground_state - String, simplified decoding

  30. Ground_temperature - Integer, in degrees Celsius

  31. Snow_ground_state - String, simplified decoding

  32. Snow_depth - In cm

  33. Ev_Evt - Evaporation (ev) or evapotranspiration (evt), in mm

  34. Sunshine_daily - In hours (generally from the previous civil day)

  35. Positive_Net_Rad_last_24h - In J/cm^2

  36. Negative_Net_Rad_last_24h - In J/cm^2

  37. Global_Solar_Rad_last_24h - In J/cm^2

  38. Diffused_Solar_Rad_last_24h - In J/cm^2

  39. Downward_LongWave_Rad_last_24h - In J/cm^2

  40. Upward_LongWave_Rad_last_24h - In J/cm^2

  41. ShortWave_Rad_last_24h - In J/cm^2

  42. Net_ShortWave_Rad_last_24h - In J/cm^2

  43. Direct_Solar_Rad_last_24h - In J/cm^2

  44. Sunshine_last_hour - In hours

  45. Positive_Net_Rad_last_hour - In kJ/m^2

  46. Negative_Net_Rad_last_hour - In kJ/m^2

  47. Global_Solar_Rad_last_hour - In kJ/m^2

  48. Diffused_Solar_Rad_last_hour - In kJ/m^2

  49. Downward_LongWave_Rad_last_hour - In kJ/m^2

  50. Upward_LongWave_Rad_last_hour - In kJ/m^2

  51. ShortWave_Rad_last_hour - In kJ/m^2

  52. Net_ShortWave_Rad_last_hour - In kJ/m^2

  53. Direct_Solar_Rad_last_hour - In kJ/m^2

  54. Cloud_drift_direction - In cardinal and intercardinal directions for "low - medium - high" clouds

  55. Cloud_elevation_direction - String indicating genera, direction and elevation angle

  56. Pressure_change_last_24h - In hPa

  57. Precipitation_S3 - In mm

  58. Precip_period_S3 - In hours ('Precipitation_S3' fell in the last 'Precip_period_S3' hours)

  59. Precipitation_last_24h - In mm

  60. Cloud_layer_1 - String indicating cover, genera and height

  61. Cloud_layer_2 - String indicating cover, genera and height

  62. Cloud_layer_3 - String indicating cover, genera and height

  63. Cloud_layer_4 - String indicating cover, genera and height

Examples

msg <- paste0("AAXX 01123 87736 32965 13205 10214 20143 ",
              "30022 40113 5//// 80005 333 10236 20128 56000 81270=")
synop_df <- data.frame(messages = msg)
decoded_data <- show_synop_data(synop_df)