# Reference EPW Parameters

![](https://3405893330-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2F-Ma9gBkJelXEQ5LsYEl7%2Fuploads%2Fgit-blob-2d37d8f957bc9f6b8d48f0dc2dba9b19eda9c681%2FReference_EPW_Parameters.png?alt=media)

![](https://3405893330-files.gitbook.io/~/files/v0/b/gitbook-legacy-files/o/assets%2F-Ma9gBkJelXEQ5LsYEl7%2Fsync%2F4bcd4346e949a4ba07aff1b7b895f167e2a73b8e.png?generation=1621529559442276\&alt=media) - [\[source code\]](https://github.com/ladybug-tools/dragonfly-grasshopper/blob/master/dragonfly_grasshopper/src/DF%20Reference%20EPW%20Parameters.py)

Create Reference EPW Site parameters that represent the properties of the stie where rural EPW data was recorded for an Urban Weather Genrator (UWG) simulation.

## Inputs

* **obstacle\_hght**

  A number that represents the height in meters of objects that obstruct the view to the sky at the weather station site. This includes both trees and buildings. (Default: 0.1 m). 
* **veg\_cover**

  A number between 0 and 1 that represents the fraction of the  reference EPW site that is covered in grass. (Default: 0.9). 
* **temp\_hght**

  A number that represents the height in meters at which temperature is measured on the weather station. (Default: 10m, the standard measurement height for US DoE EPW files). 
* **wind\_hght**

  A number that represents the height in meters at which wind speed is measured on the weather station. (Default: 10m, the standard measurement height for US DoE EPW files). 

## Outputs

* **epw\_site**

  Reference EPW site parameters that can be plugged into the "DF UWG Simulation Parameter" component to specify the behavior of vegetation in the simulation.