# How to mask out the CONUS from a netcdf file and write it again into netcdf?
**URL:** https://discourse.pangeo.io/t/how-to-mask-out-the-conus-from-a-netcdf-file-and-write-it-again-into-netcdf/2520
**Category:** Data
**Created:** [June 11, 2022, 3:14pm UTC](https://discourse.pangeo.io/t/how-to-mask-out-the-conus-from-a-netcdf-file-and-write-it-again-into-netcdf/2520 "2022-06-11T15:14:22Z")
**Posts on this page:** 2
**Page:** 1
### Author:  [@alifallahm](https://discourse.pangeo.io/u/alifallahm)
#### Post date: [June 11, 2022, 3:14pm UTC](https://discourse.pangeo.io/t/how-to-mask-out-the-conus-from-a-netcdf-file-and-write-it-again-into-netcdf/2520/1 "2022-06-11T15:14:22Z")
Hi,
Is there any efficient way to mask the Xarray’s datasets for a specific country and save that output for further analyses?
GeoCAT suggested two ways “cover” or “clip”. But the output is not suitable to save it as a netcdf file “.to\_netcdf”. It happens as the output is kind of raster.
[https://geocat-examples.readthedocs.io/en/latest/gallery/Overlays/NCL\_overlay\_11a.html#sphx-glr-gallery-overlays-ncl-overlay-11a-py](https://geocat-examples.readthedocs.io/en/latest/gallery/Overlays/NCL_overlay_11a.html#sphx-glr-gallery-overlays-ncl-overlay-11a-py)
Alternatives are suggested like : Geopandas.clip, rioxarray, salem, regionmask.
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> Can we set a shapefile as a mask for each netcdf file and run xray methods for v…alues within the shapefile region?
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> for example if I want to create a timeseries of monthly mean temperature for 'mystate' from a netcdf file that contains data for the whole country:
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> filepath = r"DATA/temp/\_/\_temp.nc"
> shapefile = r"DATA/mystate.shp"
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> ds=xray.open\_mfdataset(filepath)
> ds\_variable=ds\['temp'\]
> monthlymean=ds\_variable.resample('1MS', dim='time', how='mean')
> meanmonthlyofmystate=monthlymean.groupby('time').mean() #add somewhere here the shapefile
> meanmonthlyofmystate.to\_pandas().plot()
Here we need to install different packages which take lots of time. I would appreciate any idea/link/example on more direct solution.
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### Author:  [@alifallahm](https://discourse.pangeo.io/u/alifallahm)
#### Post date: [June 12, 2022, 6:21pm UTC](https://discourse.pangeo.io/t/how-to-mask-out-the-conus-from-a-netcdf-file-and-write-it-again-into-netcdf/2520/2 "2022-06-12T18:21:11Z")
Here I found the answer; one fantastic example using rioxarray which worked wonderfully!
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