I have accessed Anaconda Prompt for the environment that I will be working.

Once there, I have changed the directory to the place where I have the grib files that I will be working with, in order to install cfgrib, I have used the following command:

conda install -c conda-forge cfgrib

As the Python module depends on ECMWF ecCodes binary library, in the same Anaconda Prompt, I ran the following command:

conda install -c conda-forge eccodes

Then, opened the file in Spyder, and tried to run this simple script:

import xarray as xr

ds = xr.open_dataset('download.grib', engine='cfgrib')

But got the following error:

Can't read index file 'C:\Users\name\Desktop\data\download.grib.90c91.idx' Traceback (most recent call last): File "C:\Users\name\anaconda3\envs\Weather\lib\site-packages\cfgrib\messages.py", line 351, in from_indexpath_or_filestream self = cls.from_indexpath(indexpath) File "C:\Users\name\anaconda3\envs\Weather\lib\site-packages\cfgrib\messages.py", line 323, in from_indexpath return pickle.load(file) EOFError: Ran out of input


An error ocurred while starting the kernel ECCODES ERROR : Unable to find boot.def. Context path=D:/bld/eccodes_1593015095851/_h_env/Library/share/eccodes/definitions

Possible causes: ‑ The software is not correctly installed ‑ The environment variable ECCODES_DEFINITION_PATH is defined but incorrect ecCodes assertion failed: `0' in D:\bld\eccodes_1593015095851\work\src\grib_context.c:226

Error starting the kernel

What am I missing here?

Edit 1

The problem also happens if I use Visual Studio Code.

In the terminal, if I am inside the directory that the GRIB files are stored, and I activate the environment that I am working with:

conda activate Weather

And then:

& C:/Users/name/anaconda3/envs/Weather/python.exe c:/Users/name/Desktop/data/3_climate/2mtemp_open.py

It gives the same error as above.


As the error says, ECCODES_DEFINITION_PATH was not set.

As I am using Anaconda on Windows 10, the path is the following


In order to set the environment variable, one can simply run

setx ECCODES_DEFINITION_PATH "[ECCODES definition path/directory]"

This should solve the problem.

However, a new one may emerge. As the .grib file may take a lot to run, consider using the data in the format NetCDF.

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