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Radio Acoustic Sounding System (RASS) Messages, Part of the Met Office MetDB System

Update Frequency: Continual
Latest Data Update: 2022-12-14
Status: Ongoing
Online Status: ONLINE
Publication State: Published
Publication Date: 2008-08-08
Download Stats: last 12 months
Dataset Size: 4.89K Files | 3GB


The Radio Acoustic Sounding System (RASS) messages data describe hourly observations from around 120 stations distributed globally. The observations, which are later transmitted in reports, give measurements of parameters such as wind speed, and temperature. The data are collected by observation stations worldwide and transmitted within the RASS message.

Data are extracted daily at around 00 UT from the Met Office's MetDB system for the previous day's coverage.

The dataset contains measurements of the following parameters:

- Station height (in m)
- Virtual temperature (in Kelvin)
- Wind w velocity component (in m/s)
- Signal to noise ratio

See linked documentation for general information about surface station readings can be obtained from the abridged version of "MIDAS Data Users Guide", provided by the Met Office. This document describes the meteorological surface data in the Met Office Database - MIDAS. This guide is rich in information and is aimed at those with little familiarity with observing methods or instrumentation. Details of the WMO Meteorological codes used at weather observing stations (daily and hourly weather) explain the codes used in this dataset further are also linked to on this record.

Citable as:  Met Office (2008): Radio Acoustic Sounding System (RASS) Messages, Part of the Met Office MetDB System. NCAS British Atmospheric Data Centre, date of citation.
Abbreviation: Not defined
Keywords: Met Office, MetDB, RASS, profile, meteorology, temperature, wind speed, wind direction


Previous Info:
No news update for this record
Previously used record identifiers:
Access rules:
Restricted data: please submit an application using the REQUEST ACCESS link for access.
Use of these data is covered by the following licence: When using these data you must cite them correctly using the citation given on the CEDA Data Catalogue record.
Data lineage:

Data are extracted from the Met Office's "metDB" system and supplied to Centre for Environmental Data Analysis. These are then processed to generate BADC-CSV files, where possible.

Data Quality:
Land and ship SYNOP messages undergo some quality control at the Met Office, but these messages are not as rigorously checked as they are within the MIDAS system into which the data are later migrated. Thus, for historic data the MIDAS dataset is the recommended dataset to use for surface observations.
File Format:
Data are BADC-CSV formatted

Process overview

This dataset was generated by instruments deployed on platforms as listed below.
Output Description


  • units: m
  • long_name: Height
  • long_name: Signa to noise ratio
  • units: DB
  • units: 1
  • long_name: Vertical wind quality control information
  • units: K
  • long_name: Virtual temperature
  • units: 1
  • long_name: Virtual temperature quality control information
  • units: m/s
  • long_name: Wind w component

Co-ordinate Variables

Temporal Range
Start time:
End time:
Geographic Extent

Related parties
Authors (1)
Principal Investigators (1)