About the ACCESS model

The Australian Community Climate and Earth-System Simulator (ACCESS) weather models have been developed and tested by research staff from the Centre for Australian Weather and Climate Research (CAWCR) and are based on the UK Meteorological Office's Unified Model. The ACCESS suite of models has shown a significant improvement in accuracy over the Bureau's old weather model suite (GASP, LAPS and MesoLAPS), and output is available in map form or as gridded data products.

Model ACCESS-G
Version APS1
Domain Global
Resolution Approximately 40km
Time Step and Duration 6 hourly to 240 hours (10 days)
Model Run Times and Typical Availability Times 00Z run available 0640Z
12Z run available 1840Z
Views Global
Southern Hemisphere
Australia
Indian Ocean
Pacific Ocean
Available Elements Mean sea level pressure (MSLP) & rainfall
Surface winds
MSLP & thickness
Wind speed and direction at 10m, 850hPa, 700hPa, 500hPa, 200hPa, and gradient
Geopotential height at 850hPa, 700hPa, 500hPa, and 200hPa
Temperature at 2m screen, 850hPa, 700hPa, 500hPa, 200hPa
2m screen dew point
Relative humidity at 2m screen, 850hPa, 700hPa, 500hPa, and 200hPa
Other fields available as gridded data
Model ACCESS-R
Version APS1
Domain Regional
Resolution 0.11° (~12km)
Time Step and Duration 3 hourly to 72 hours (3 days)
Model Run Times and Typical Availability Times 00Z run available 0330Z
06Z run available 0945Z
12Z run available 1530Z
18Z run available 2130Z

N.B. All runs available one hour earlier during the daylight saving period.
Views Full domain
Australia
Available Elements

Mean sea level pressure (MSLP) & rainfall
Surface winds

MSLP & thickness
Wind speed and direction at 10m, 850hPa, 700hPa, 500hPa, 200hPa, and gradient
Geopotential height at 850hPa, 700hPa, 500hPa, and 200hPa
Temperature at 2m screen, 850hPa, 700hPa, 500hPa, 200hPa
2m screen dew point
Relative humidity at 2m screen, 850hPa, 700hPa, 500hPa, and 200hPa
Other fields available as gridded data.
Model ACCESS-C+
Version APS1
Domain City :
Victoria/Tasmania
Sydney
Brisbane
Adelaide
Perth
Resolution 0.036° (~4km)
Time Step and Duration 1 hourly to 36 hours (1.5 days)
Model Run Times and Typical Availability Times 00Z run available 0325Z
06Z run available  0935Z
12Z run available 1525Z
18Z run available  2125Z

N.B. All runs available one hour earlier during the daylight saving period.
Views Not applicable
Available Elements Available as gridded data only
Model ACCESS-TC
Version APS1
Domain 3 relocatable domains
Resolution 0.11° (~12km)
Time Step and Duration 1 hourly to 72 hours (3 days)
Model Run Times and Typical Availability Times Run on demand
Views Not applicable
Available Elements Available as gridded data only

Upper air charts are generally labelled with the pressure level in hectopascals (hPa), e.g. 500 hPa. The pressure decreases as altitude increases. For instance, the 250 hPa level is higher than the 500 hPa level. For some fields there are also charts representing the atmosphere 2 metres and 10 metres above the ground, and at the "gradient" level which lies about 1000 metres above the earth's surface and is the level most representative of the air flow in the lower atmosphere immediately above the layer affected by surface friction. This level is free of local wind and topographic effects (such as sea breezes, downslope winds etc).

Some charts show geopotential height, which approximates the actual height of a pressure surface above mean sea-level. Therefore, geopotential height contours on a particular map, e.g. 850 hPa, represent the height of that pressure surface.

Charts showing precipitation represent the amount of rainfall in millimetres which is forecast to fall at the ground over the preceding 3 or 6 hours. The period is shown in the chart heading as "3 hrly" or "6 hrly".

For more details about the ACCESS systems see the following Bureau National Operations Centre (BNOC) Operations Bulletins:

Users interested in accessing raw data via FTP should refer to the ACCESS NWP Data Documentation.