BOM Weather Data

Overview

This dataset is built from Australian Bureau of Meteorology's (BOM) automated weather station historical datasets and current observations. Omnata combines, cleans and normalizes these datasets for consumption via Snowflake. Omnata maintains the a production ETL pipeline from BOM servers, has an uptime status page and automated outage recovery.

Dataset summary

Half-hourly (and sub-hourly) weather observations from 858 automated and manual weather stations across Australia and Antarctica, spanning October 1948 to present day. Updated continuously.

Total Observations	251.5 million
Stations	858 reporting stations (of 19,491 in reference catalogue)
Time Span	October 1948 - present (77+ years)
Typical Frequency	~48 observations per station per day
Geographic Scope	All Australian states/territories + Antarctic stations

The reason the dataset only covers 858 of ~19k possible stations is that the majority of BOM stations are historical or single measurement. For example, only ~8000 stations are active today and ~6000 are volunteer run to measure only rainfall.

Key Coverage Changes Over Time

1. 1948-1984: Limited to 1-3 stations in NSW/VIC. Minimal rainfall data captured.

2. 1985-1999: Network expanded rapidly from 10 to 351 stations. Rainfall recording became standard (~86% complete).

3. 2000-2016: Steady growth to ~560 stations. Observation frequency increased with automation.

4. 2017-present: Network reached 620+ stations. A further expansion in 2025 added ~150 stations, bringing the total to 773.

What's Included

Observations (38 columns): air temperature, apparent temperature, dewpoint, relative humidity, wind speed/direction/gust, atmospheric pressure (MSL and QNH), rainfall (hourly, 10-minute, cumulative since 9am), cloud cover/base/type, visibility, sea state, swell, and weather description.

Station Reference (11 columns): station number, WMO code, name, operating years, geographic coordinates (lat/lon as GEOGRAPHY), state, elevation, barometer height, and timezone.

Join key: STATION_NUMBER

Coverage by State

Observations by State (millions)

NSW  |████████████████████████████████████████████████████████  56.4M
QLD  |█████████████████████████████████████████████▉            45.9M
VIC  |████████████████████████████████████████▎                 40.3M
WA   |███████████████████████████████████████▌                  39.5M
SA   |███████████████████████████▎                              27.3M
TAS  |████████████████████                                      20.0M
NT   |████████████████▌                                         16.5M
ANT  |██▌                                                        2.5M

State	Stations	Oldest data begins
NSW	217	1948
QLD	168	1985
VIC	108	1970
WA	147	1985
SA	88	1985
TAS	57	1984
NT	63	1985
ANT	10	1994

Metric Completeness

Metric	Overall	Pre-1990	1990-2009	2010-present
Air temperature	94%	95%	95%	94%
Humidity / Dewpoint	91%	95%	93%	89%
Wind speed & direction	96%	100%	99%	95%
Atmospheric pressure	78%	91%	77%	79%
Rainfall (cumulative)	88%	5%	86%	90%
Rainfall (hourly)	88%	5%	86%	90%

Apparent temperature, gust, cloud oktas, visibility, and weather descriptions have low completeness (<10%) as they depend on manual observation or specific sensor configurations.

Important notes for analysis:

• Rainfall fields are unreliable before 1990 (only 5% populated)

• Pressure completeness dropped from ~91% to ~77% post-1990 as stations without barometers were added

• Sub-hourly data density varies by station; some report every 1-2 minutes, others at 30-minute intervals

Station Network Growth

Active Stations Over Time

800 |                                                                    *
    |                                                                 *
700 |
    |
600 |                                          * * * * * * * * * *
    |                                     *  *
500 |                              * * * *
    |                          * *
400 |                      * *
    |                   *
300 |                *
    |            *
200 |         *
    |       *
100 |    *
    | *
  0 +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+-
    1985  1988  1991  1994  1997  2000  2003  2006  2009  2012  2015  2018  2021  2024

Dataset Schema

Core Observation Fields

Field	Type	Description	Units
station_id	String	Unique BOM station identifier	-
station_name	String	Human-readable station name	-
observation_time	Timestamp	Date and time of observation (local time)	ISO 8601
observation_time_utc	Timestamp	Date and time of observation (UTC)	ISO 8601
latitude	Float	Station latitude	Decimal degrees
longitude	Float	Station longitude	Decimal degrees
elevation	Integer	Station elevation above sea level	Meters

Weather Measurements

Field	Type	Description	Units
air_temperature	Float	Air temperature	°C
apparent_temperature	Float	Apparent temperature (feels like)	°C
dew_point	Float	Dew point temperature	°C
relative_humidity	Integer	Relative humidity	%
wind_direction	String	Wind direction (compass point)	Cardinal/Ordinal
wind_direction_degrees	Integer	Wind direction	Degrees (0-360)
wind_speed_kmh	Float	Wind speed	km/h
wind_gust_kmh	Float	Wind gust speed	km/h
pressure_msl	Float	Mean sea level pressure	hPa
pressure_qnh	Float	QNH pressure	hPa
rainfall_since_9am	Float	Rainfall since 9am local time	mm
visibility	Integer	Visibility	km
cloud_cover	String	Cloud cover description	Text
weather_description	String	Current weather conditions	Text

Data Quality Indicators

Field	Type	Description
data_quality	String	Quality assessment (Good/Fair/Poor)
automatic_station	Boolean	Whether station is automated (AWS)
last_updated	Timestamp	When record was last updated

Data Freshness

• Update Frequency: Daily

• Granularity: 30mins

Lower latency data available get in touch to request

Usage Examples

Basic Query

-- Get latest observations for Sydney area stations
SELECT station_name, observation_time, air_temperature, 
       wind_speed_kmh, rainfall_since_9am
FROM OBSERVATIONS
WHERE station_name LIKE '%SYDNEY%'
  AND observation_time >= CURRENT_TIMESTAMP - INTERVAL '24 HOURS'
ORDER BY observation_time DESC;

Temperature Analysis

-- Find stations with extreme temperatures in last 24 hours
SELECT station_name, state, 
       MAX(air_temperature) as max_temp,
       MIN(air_temperature) as min_temp,
       AVG(air_temperature) as avg_temp
FROM OBSERVATIONS 
WHERE observation_time >= CURRENT_TIMESTAMP - INTERVAL '24 HOURS'
  AND air_temperature IS NOT NULL
GROUP BY station_name, state
HAVING MAX(air_temperature) > 35 OR MIN(air_temperature) < 5
ORDER BY max_temp DESC;

Compliance and Attribution

This dataset is derived from the Australian Bureau of Meteorology's publicly available weather observations. Usage complies with BOM's data licensing terms. Original data remains the property of the Commonwealth of Australia, Bureau of Meteorology.