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Unable to read NCEP MRMS grib2 files

See original GitHub issue

I’m on OSX and have installed xarray and cfgrib through Anaconda/conda-forge:

$ python --version
Python 3.8.0
$ conda env export
name: mypy3env
channels:
  - conda-forge
  - defaults
dependencies:
...
  - cfgrib=0.9.7.3=py_0
...
  - eccodes=2.14.1=ha74ff94_3
...
  - xarray=0.14.1=py_0

I’m trying to work with NCEP MultiRadar MultiSensor grib2s such as in https://mrms.ncep.noaa.gov/data/2D/MergedReflectivityQCComposite/ , and always getting the following output/traceback reading files in:

$ cfgrib to_netcdf MRMS_MergedReflectivityQCComposite_00.50_20191209-210032.grib2
libpng warning: Application built with libpng-1.4.12 but running with 1.6.37
ECCODES ERROR   :  unable to get values as double array (Decoding invalid)
ECCODES ERROR   :  unable to create iterator
Traceback (most recent call last):
  File "/Users/dian/work/anaconda/envs/mypy3env/bin/cfgrib", line 10, in <module>
    sys.exit(cfgrib_cli())
  File "/Users/dian/work/anaconda/envs/mypy3env/lib/python3.8/site-packages/click/core.py", line 764, in __call__
    return self.main(*args, **kwargs)
  File "/Users/dian/work/anaconda/envs/mypy3env/lib/python3.8/site-packages/click/core.py", line 717, in main
    rv = self.invoke(ctx)
  File "/Users/dian/work/anaconda/envs/mypy3env/lib/python3.8/site-packages/click/core.py", line 1137, in invoke
    return _process_result(sub_ctx.command.invoke(sub_ctx))
  File "/Users/dian/work/anaconda/envs/mypy3env/lib/python3.8/site-packages/click/core.py", line 956, in invoke
    return ctx.invoke(self.callback, **ctx.params)
  File "/Users/dian/work/anaconda/envs/mypy3env/lib/python3.8/site-packages/click/core.py", line 555, in invoke
    return callback(*args, **kwargs)
  File "/Users/dian/work/anaconda/envs/mypy3env/lib/python3.8/site-packages/cfgrib/__main__.py", line 56, in to_netcdf
    ds = xr.open_mfdataset(inpaths, engine=engine)
  File "/Users/dian/work/anaconda/envs/mypy3env/lib/python3.8/site-packages/xarray/backends/api.py", line 900, in open_mfdataset
    datasets = [open_(p, **open_kwargs) for p in paths]
  File "/Users/dian/work/anaconda/envs/mypy3env/lib/python3.8/site-packages/xarray/backends/api.py", line 900, in <listcomp>
    datasets = [open_(p, **open_kwargs) for p in paths]
  File "/Users/dian/work/anaconda/envs/mypy3env/lib/python3.8/site-packages/xarray/backends/api.py", line 516, in open_dataset
    store = backends.CfGribDataStore(
  File "/Users/dian/work/anaconda/envs/mypy3env/lib/python3.8/site-packages/xarray/backends/cfgrib_.py", line 43, in __init__
    self.ds = cfgrib.open_file(filename, **backend_kwargs)
  File "/Users/dian/work/anaconda/envs/mypy3env/lib/python3.8/site-packages/cfgrib/dataset.py", line 628, in open_file
    return Dataset(*build_dataset_components(index, read_keys=read_keys, **kwargs))
  File "/Users/dian/work/anaconda/envs/mypy3env/lib/python3.8/site-packages/cfgrib/dataset.py", line 542, in build_dataset_components
    dims, data_var, coord_vars = build_variable_components(
  File "/Users/dian/work/anaconda/envs/mypy3env/lib/python3.8/site-packages/cfgrib/dataset.py", line 476, in build_variable_components
    geo_dims, geo_shape, geo_coord_vars = build_geography_coordinates(index, encode_cf, errors)
  File "/Users/dian/work/anaconda/envs/mypy3env/lib/python3.8/site-packages/cfgrib/dataset.py", line 357, in build_geography_coordinates
    latitudes = np.array(first['distinctLatitudes'])
  File "/Users/dian/work/anaconda/envs/mypy3env/lib/python3.8/site-packages/cfgrib/messages.py", line 178, in __getitem__
    return super(ComputedKeysMessage, self).__getitem__(item)
  File "/Users/dian/work/anaconda/envs/mypy3env/lib/python3.8/site-packages/cfgrib/messages.py", line 130, in __getitem__
    return self.message_get(item)
  File "/Users/dian/work/anaconda/envs/mypy3env/lib/python3.8/site-packages/cfgrib/messages.py", line 92, in message_get
    values = eccodes.codes_get_array(self.codes_id, item, key_type)
  File "/Users/dian/work/anaconda/envs/mypy3env/lib/python3.8/site-packages/cfgrib/bindings.py", line 365, in codes_get_array
    size = codes_get_size(handle, key)
  File "/Users/dian/work/anaconda/envs/mypy3env/lib/python3.8/site-packages/cfgrib/bindings.py", line 216, in codes_get_size
    _codes_get_size(handle, key.encode(ENC), size)
  File "/Users/dian/work/anaconda/envs/mypy3env/lib/python3.8/site-packages/cfgrib/bindings.py", line 165, in wrapper
    raise GribInternalError(code)
cfgrib.bindings.GribInternalError: ('Decoding invalid (-13).', -13)