Surface Weather Observations (24 hour)

Brief description

Surface weather observations are recorded half hourly, primarily from aerodromes with some additional data coming from unmanned automatic weather stations. In special conditions, observations may be made earlier and for cost savings, some stations may only report hourly. The following data are recorded: datetime, id_num (WMO index number, normally a unique id, but can be missing), id_name (abbreviated name, used to identify the observing site), date, time, wdir (wind direction, degrees from N), wspd (wind speed, knots), t_db (temperature dry bulb, degree C), dp (dew point, degree C), qnh (aircraft altimeter setting, hPa), rf9am (rainfall since 9am, mm), rf10m (rainfall last 10 minutes, mm), vic (visibility, m), avis (automatically measured visibility, m), gust (maximum wind gust last 10 minutes, knots), wx1int (first (most important) present weather intensity), wx1dsc (first (most important) present weather qualifier), wx1wx1 (first (most important) present weather type), wx1wx2 (additional weather type for mixed precipitation), wx1wx3 (additional weather type for mixed precipitation), wx2int (second (less important) present weather intensity), wx2dsc (second (less important) present weather qualifier), wx2wx1 (second (less important) present weather type), wx2wx2 (additional weather type for mixed precipitation), wx2wx3 (additional weather type for mixed precipitation), cld1amt (lowest cloud layer amount), cld1typ (lowest cloud layer type), cld1typ (lowest cloud layer base, m), cld2amt (second cloud layer amount), cld1typ (second cloud layer type), cld1base (second cloud layer base, m), cld3amt (third cloud layer amount), cld3typ (third cloud layer type), cld3base (lowest cloud layer base, m), cld4amt (fourth cloud amount), cld4typ (fourth cloud layer type), cld4base (fourth cloud layer base, m), ceil1amt (lowest cloud layer amount measured by ceilometer), ceil1base (lowest cloud layer base measured by ceilometer, m), ceil2amt (second cloud layer amount measured by ceilometer), ceil2base (second cloud layer base measured by ceilometer, m), ceil3amt (third cloud layer amount measured by ceilometer), ceil1base (third cloud layer base measured by ceilometer, m), rotation (required for rotation of wind barbs in MapServer), rh (relative humidity, %), stn_name (full station name). A record of the last 24 hours is available for each station. Information about codes can be found at http://www.bom.gov.au/weather-services/about/IDY03100.doc