🧭 CRS with MetPy

What if you need to manually attach coordinate reference system because metpy can’t detect it?

from herbie import Herbie
import metpy

H = Herbie("2021-01-25 06:00", model="hrrr")

✅ Found ┊ model=hrrr ┊ product=sfc ┊ 2021-Jan-25 06:00 UTC F00 ┊ GRIB2 @ aws ┊ IDX @ aws

ds = H.xarray("TMP:2 m")

👨🏻‍🏭 Created directory: [C:\Users\blaylock\data\hrrr\20210125]

C:\Users\blaylock\_GITHUB\Herbie\herbie\archive.py:1041: UserWarning: sorry, on windows I couldn't remove the file.
  warnings.warn("sorry, on windows I couldn't remove the file.")

ds

<xarray.Dataset>
Dimensions:              (y: 1059, x: 1799)
Coordinates:
    time                 datetime64[ns] 2021-01-25T06:00:00
    step                 timedelta64[ns] 00:00:00
    heightAboveGround    float64 2.0
    latitude             (y, x) float64 21.14 21.15 21.15 ... 47.86 47.85 47.84
    longitude            (y, x) float64 237.3 237.3 237.3 ... 299.0 299.0 299.1
    valid_time           datetime64[ns] 2021-01-25T06:00:00
Dimensions without coordinates: y, x
Data variables:
    t2m                  (y, x) float32 292.3 292.3 292.3 ... 272.9 272.9 273.0
    gribfile_projection  object None
Attributes:
    GRIB_edition:            2
    GRIB_centre:             kwbc
    GRIB_centreDescription:  US National Weather Service - NCEP
    GRIB_subCentre:          0
    Conventions:             CF-1.7
    institution:             US National Weather Service - NCEP
    model:                   hrrr
    product:                 sfc
    description:             High-Resolution Rapid Refresh - CONUS
    remote_grib:             https://noaa-hrrr-bdp-pds.s3.amazonaws.com/hrrr....
    local_grib:              C:\Users\blaylock\data\hrrr\20210125\subset_f7ef...
    searchString:            TMP:2 m

xarray.Dataset

• Dimensions:
  • y: 1059
  • x: 1799
• Coordinates: (6)
  • time
    ()
    datetime64[ns]
    2021-01-25T06:00:00

    long_name :

    initial time of forecast

    standard_name :

    forecast_reference_time

    array('2021-01-25T06:00:00.000000000', dtype='datetime64[ns]')

  • step
    ()
    timedelta64[ns]
    00:00:00

    long_name :

    time since forecast_reference_time

    standard_name :

    forecast_period

    array(0, dtype='timedelta64[ns]')

  • heightAboveGround
    ()
    float64
    2.0

    long_name :

    height above the surface

    units :

    m

    positive :

    up

    standard_name :

    height

    array(2.)

  • latitude
    (y, x)
    float64
    21.14 21.15 21.15 ... 47.85 47.84

    units :

    degrees_north

    standard_name :

    latitude

    long_name :

    latitude

    array([[21.138123  , 21.14511004, 21.1520901 , ..., 21.1545089 ,
            21.14753125, 21.14054663],
           [21.16299459, 21.1699845 , 21.17696744, ..., 21.17938723,
            21.1724067 , 21.16541921],
           [21.18786863, 21.19486142, 21.20184723, ..., 21.20426802,
            21.19728462, 21.19029425],
           ...,
           [47.78955926, 47.799849  , 47.81012868, ..., 47.81369093,
            47.80341474, 47.79312849],
           [47.81409316, 47.82438621, 47.8346692 , ..., 47.83823259,
            47.8279531 , 47.81766354],
           [47.8386235 , 47.84891986, 47.85920615, ..., 47.86277069,
            47.85248789, 47.84219502]])

  • longitude
    (y, x)
    float64
    237.3 237.3 237.3 ... 299.0 299.1

    units :

    degrees_east

    standard_name :

    longitude

    long_name :

    longitude

    array([[237.280472  , 237.30713868, 237.3338097 , ..., 287.6569408 ,
            287.68361332, 287.71028151],
           [237.27297501, 237.29964881, 237.32632695, ..., 287.66442108,
            287.69110073, 287.71777603],
           [237.26547368, 237.2921546 , 237.31883986, ..., 287.6719057 ,
            287.69859247, 287.7252749 ],
           ...,
           [225.9351904 , 225.97171577, 226.00825329, ..., 298.97907406,
            299.0156158 , 299.05214538],
           [225.91986142, 225.95639874, 225.99294822, ..., 298.99437498,
            299.03092868, 299.06747022],
           [225.90452027, 225.94106954, 225.97763099, ..., 299.00968806,
            299.04625373, 299.08280723]])

  • valid_time
    ()
    datetime64[ns]
    2021-01-25T06:00:00

    standard_name :

    time

    long_name :

    time

    array('2021-01-25T06:00:00.000000000', dtype='datetime64[ns]')

• Data variables: (2)
  • t2m
    (y, x)
    float32
    292.3 292.3 292.3 ... 272.9 273.0

    GRIB_paramId :

    167

    GRIB_dataType :

    fc

    GRIB_numberOfPoints :

    1905141

    GRIB_typeOfLevel :

    heightAboveGround

    GRIB_stepUnits :

    1

    GRIB_stepType :

    instant

    GRIB_gridType :

    lambert

    GRIB_DxInMetres :

    3000.0

    GRIB_DyInMetres :

    3000.0

    GRIB_LaDInDegrees :

    38.5

    GRIB_Latin1InDegrees :

    38.5

    GRIB_Latin2InDegrees :

    38.5

    GRIB_LoVInDegrees :

    262.5

    GRIB_NV :

    0

    GRIB_Nx :

    1799

    GRIB_Ny :

    1059

    GRIB_cfName :

    air_temperature

    GRIB_cfVarName :

    t2m

    GRIB_gridDefinitionDescription :

    Lambert Conformal can be secant or tangent, conical or bipolar

    GRIB_iScansNegatively :

    0

    GRIB_jPointsAreConsecutive :

    0

    GRIB_jScansPositively :

    1

    GRIB_latitudeOfFirstGridPointInDegrees :

    21.138123

    GRIB_latitudeOfSouthernPoleInDegrees :

    0.0

    GRIB_longitudeOfFirstGridPointInDegrees :

    237.280472

    GRIB_longitudeOfSouthernPoleInDegrees :

    0.0

    GRIB_missingValue :

    3.4028234663852886e+38

    GRIB_name :

    2 metre temperature

    GRIB_parameterName :

    Temperature

    GRIB_parameterUnits :

    K

    GRIB_shortName :

    2t

    GRIB_stepRange :

    0

    GRIB_units :

    K

    long_name :

    2 metre temperature

    units :

    K

    standard_name :

    air_temperature

    grid_mapping :

    gribfile_projection

    array([[292.281 , 292.281 , 292.281 , ..., 298.0935, 298.0935, 298.0935],
           [292.281 , 292.281 , 292.281 , ..., 298.0935, 298.0935, 298.0935],
           [292.281 , 292.281 , 292.281 , ..., 298.031 , 298.031 , 298.031 ],
           ...,
           [280.2185, 280.156 , 280.156 , ..., 272.8435, 272.906 , 272.906 ],
           [280.156 , 280.156 , 280.0935, ..., 272.8435, 272.906 , 272.9685],
           [280.156 , 280.156 , 280.0935, ..., 272.906 , 272.906 , 272.9685]],
          dtype=float32)

  • gribfile_projection
    ()
    object
    None

    crs_wkt :

    PROJCRS["unknown",BASEGEOGCRS["unknown",DATUM["unknown",ELLIPSOID["unknown",6371229,0,LENGTHUNIT["metre",1,ID["EPSG",9001]]]],PRIMEM["Greenwich",0,ANGLEUNIT["degree",0.0174532925199433],ID["EPSG",8901]]],CONVERSION["unknown",METHOD["Lambert Conic Conformal (2SP)",ID["EPSG",9802]],PARAMETER["Latitude of false origin",38.5,ANGLEUNIT["degree",0.0174532925199433],ID["EPSG",8821]],PARAMETER["Longitude of false origin",262.5,ANGLEUNIT["degree",0.0174532925199433],ID["EPSG",8822]],PARAMETER["Latitude of 1st standard parallel",38.5,ANGLEUNIT["degree",0.0174532925199433],ID["EPSG",8823]],PARAMETER["Latitude of 2nd standard parallel",38.5,ANGLEUNIT["degree",0.0174532925199433],ID["EPSG",8824]],PARAMETER["Easting at false origin",0,LENGTHUNIT["metre",1],ID["EPSG",8826]],PARAMETER["Northing at false origin",0,LENGTHUNIT["metre",1],ID["EPSG",8827]]],CS[Cartesian,2],AXIS["(E)",east,ORDER[1],LENGTHUNIT["metre",1,ID["EPSG",9001]]],AXIS["(N)",north,ORDER[2],LENGTHUNIT["metre",1,ID["EPSG",9001]]]]

    semi_major_axis :

    6371229.0

    semi_minor_axis :

    6371229.0

    inverse_flattening :

    0.0

    reference_ellipsoid_name :

    unknown

    longitude_of_prime_meridian :

    0.0

    prime_meridian_name :

    Greenwich

    geographic_crs_name :

    unknown

    horizontal_datum_name :

    unknown

    projected_crs_name :

    unknown

    grid_mapping_name :

    lambert_conformal_conic

    standard_parallel :

    (38.5, 38.5)

    latitude_of_projection_origin :

    38.5

    longitude_of_central_meridian :

    262.5

    false_easting :

    0.0

    false_northing :

    0.0

    long_name :

    HRRR model grid projection

    array(None, dtype=object)

• Indexes: (0)
• Attributes: (12)

  GRIB_edition :

  2

  GRIB_centre :

  kwbc

  GRIB_centreDescription :

  US National Weather Service - NCEP

  GRIB_subCentre :

  0

  Conventions :

  CF-1.7

  institution :

  US National Weather Service - NCEP

  model :

  hrrr

  product :

  sfc

  description :

  High-Resolution Rapid Refresh - CONUS

  remote_grib :

  https://noaa-hrrr-bdp-pds.s3.amazonaws.com/hrrr.20210125/conus/hrrr.t06z.wrfsfcf00.grib2

  local_grib :

  C:\Users\blaylock\data\hrrr\20210125\subset_f7effd54__hrrr.t06z.wrfsfcf00.grib2

  searchString :

  TMP:2 m

ds.metpy.assign_crs(
    dict(
        grid_mapping_name="lambert_conformal_conic",
        standard_parallel=(38.5, 38.5),
        latitude_of_projection_origin=38.5,
        longitude_of_central_meridian=262.5,
    )
)

<xarray.Dataset>
Dimensions:              (y: 1059, x: 1799)
Coordinates:
    time                 datetime64[ns] 2021-01-25T06:00:00
    step                 timedelta64[ns] 00:00:00
    heightAboveGround    float64 2.0
    latitude             (y, x) float64 21.14 21.15 21.15 ... 47.86 47.85 47.84
    longitude            (y, x) float64 237.3 237.3 237.3 ... 299.0 299.0 299.1
    valid_time           datetime64[ns] 2021-01-25T06:00:00
    metpy_crs            object Projection: lambert_conformal_conic
Dimensions without coordinates: y, x
Data variables:
    t2m                  (y, x) float32 292.3 292.3 292.3 ... 272.9 272.9 273.0
    gribfile_projection  object None
Attributes:
    GRIB_edition:            2
    GRIB_centre:             kwbc
    GRIB_centreDescription:  US National Weather Service - NCEP
    GRIB_subCentre:          0
    Conventions:             CF-1.7
    institution:             US National Weather Service - NCEP
    model:                   hrrr
    product:                 sfc
    description:             High-Resolution Rapid Refresh - CONUS
    remote_grib:             https://noaa-hrrr-bdp-pds.s3.amazonaws.com/hrrr....
    local_grib:              C:\Users\blaylock\data\hrrr\20210125\subset_f7ef...
    searchString:            TMP:2 m

xarray.Dataset

• Dimensions:
  • y: 1059
  • x: 1799
• Coordinates: (7)
  • time
    ()
    datetime64[ns]
    2021-01-25T06:00:00

    long_name :

    initial time of forecast

    standard_name :

    forecast_reference_time

    array('2021-01-25T06:00:00.000000000', dtype='datetime64[ns]')

  • step
    ()
    timedelta64[ns]
    00:00:00

    long_name :

    time since forecast_reference_time

    standard_name :

    forecast_period

    array(0, dtype='timedelta64[ns]')

  • heightAboveGround
    ()
    float64
    2.0

    long_name :

    height above the surface

    units :

    m

    positive :

    up

    standard_name :

    height

    array(2.)

  • latitude
    (y, x)
    float64
    21.14 21.15 21.15 ... 47.85 47.84

    units :

    degrees_north

    standard_name :

    latitude

    long_name :

    latitude

    array([[21.138123  , 21.14511004, 21.1520901 , ..., 21.1545089 ,
            21.14753125, 21.14054663],
           [21.16299459, 21.1699845 , 21.17696744, ..., 21.17938723,
            21.1724067 , 21.16541921],
           [21.18786863, 21.19486142, 21.20184723, ..., 21.20426802,
            21.19728462, 21.19029425],
           ...,
           [47.78955926, 47.799849  , 47.81012868, ..., 47.81369093,
            47.80341474, 47.79312849],
           [47.81409316, 47.82438621, 47.8346692 , ..., 47.83823259,
            47.8279531 , 47.81766354],
           [47.8386235 , 47.84891986, 47.85920615, ..., 47.86277069,
            47.85248789, 47.84219502]])

  • longitude
    (y, x)
    float64
    237.3 237.3 237.3 ... 299.0 299.1

    units :

    degrees_east

    standard_name :

    longitude

    long_name :

    longitude

    array([[237.280472  , 237.30713868, 237.3338097 , ..., 287.6569408 ,
            287.68361332, 287.71028151],
           [237.27297501, 237.29964881, 237.32632695, ..., 287.66442108,
            287.69110073, 287.71777603],
           [237.26547368, 237.2921546 , 237.31883986, ..., 287.6719057 ,
            287.69859247, 287.7252749 ],
           ...,
           [225.9351904 , 225.97171577, 226.00825329, ..., 298.97907406,
            299.0156158 , 299.05214538],
           [225.91986142, 225.95639874, 225.99294822, ..., 298.99437498,
            299.03092868, 299.06747022],
           [225.90452027, 225.94106954, 225.97763099, ..., 299.00968806,
            299.04625373, 299.08280723]])

  • valid_time
    ()
    datetime64[ns]
    2021-01-25T06:00:00

    standard_name :

    time

    long_name :

    time

    array('2021-01-25T06:00:00.000000000', dtype='datetime64[ns]')

  • metpy_crs
    ()
    object
    Projection: lambert_conformal_conic

    array(<metpy.plots.mapping.CFProjection object at 0x000001E41D825900>,
          dtype=object)

• Data variables: (2)
  • t2m
    (y, x)
    float32
    292.3 292.3 292.3 ... 272.9 273.0

    GRIB_paramId :

    167

    GRIB_dataType :

    fc

    GRIB_numberOfPoints :

    1905141

    GRIB_typeOfLevel :

    heightAboveGround

    GRIB_stepUnits :

    1

    GRIB_stepType :

    instant

    GRIB_gridType :

    lambert

    GRIB_DxInMetres :

    3000.0

    GRIB_DyInMetres :

    3000.0

    GRIB_LaDInDegrees :

    38.5

    GRIB_Latin1InDegrees :

    38.5

    GRIB_Latin2InDegrees :

    38.5

    GRIB_LoVInDegrees :

    262.5

    GRIB_NV :

    0

    GRIB_Nx :

    1799

    GRIB_Ny :

    1059

    GRIB_cfName :

    air_temperature

    GRIB_cfVarName :

    t2m

    GRIB_gridDefinitionDescription :

    Lambert Conformal can be secant or tangent, conical or bipolar

    GRIB_iScansNegatively :

    0

    GRIB_jPointsAreConsecutive :

    0

    GRIB_jScansPositively :

    1

    GRIB_latitudeOfFirstGridPointInDegrees :

    21.138123

    GRIB_latitudeOfSouthernPoleInDegrees :

    0.0

    GRIB_longitudeOfFirstGridPointInDegrees :

    237.280472

    GRIB_longitudeOfSouthernPoleInDegrees :

    0.0

    GRIB_missingValue :

    3.4028234663852886e+38

    GRIB_name :

    2 metre temperature

    GRIB_parameterName :

    Temperature

    GRIB_parameterUnits :

    K

    GRIB_shortName :

    2t

    GRIB_stepRange :

    0

    GRIB_units :

    K

    long_name :

    2 metre temperature

    units :

    K

    standard_name :

    air_temperature

    grid_mapping :

    gribfile_projection

    array([[292.281 , 292.281 , 292.281 , ..., 298.0935, 298.0935, 298.0935],
           [292.281 , 292.281 , 292.281 , ..., 298.0935, 298.0935, 298.0935],
           [292.281 , 292.281 , 292.281 , ..., 298.031 , 298.031 , 298.031 ],
           ...,
           [280.2185, 280.156 , 280.156 , ..., 272.8435, 272.906 , 272.906 ],
           [280.156 , 280.156 , 280.0935, ..., 272.8435, 272.906 , 272.9685],
           [280.156 , 280.156 , 280.0935, ..., 272.906 , 272.906 , 272.9685]],
          dtype=float32)

  • gribfile_projection
    ()
    object
    None

    crs_wkt :

    PROJCRS["unknown",BASEGEOGCRS["unknown",DATUM["unknown",ELLIPSOID["unknown",6371229,0,LENGTHUNIT["metre",1,ID["EPSG",9001]]]],PRIMEM["Greenwich",0,ANGLEUNIT["degree",0.0174532925199433],ID["EPSG",8901]]],CONVERSION["unknown",METHOD["Lambert Conic Conformal (2SP)",ID["EPSG",9802]],PARAMETER["Latitude of false origin",38.5,ANGLEUNIT["degree",0.0174532925199433],ID["EPSG",8821]],PARAMETER["Longitude of false origin",262.5,ANGLEUNIT["degree",0.0174532925199433],ID["EPSG",8822]],PARAMETER["Latitude of 1st standard parallel",38.5,ANGLEUNIT["degree",0.0174532925199433],ID["EPSG",8823]],PARAMETER["Latitude of 2nd standard parallel",38.5,ANGLEUNIT["degree",0.0174532925199433],ID["EPSG",8824]],PARAMETER["Easting at false origin",0,LENGTHUNIT["metre",1],ID["EPSG",8826]],PARAMETER["Northing at false origin",0,LENGTHUNIT["metre",1],ID["EPSG",8827]]],CS[Cartesian,2],AXIS["(E)",east,ORDER[1],LENGTHUNIT["metre",1,ID["EPSG",9001]]],AXIS["(N)",north,ORDER[2],LENGTHUNIT["metre",1,ID["EPSG",9001]]]]

    semi_major_axis :

    6371229.0

    semi_minor_axis :

    6371229.0

    inverse_flattening :

    0.0

    reference_ellipsoid_name :

    unknown

    longitude_of_prime_meridian :

    0.0

    prime_meridian_name :

    Greenwich

    geographic_crs_name :

    unknown

    horizontal_datum_name :

    unknown

    projected_crs_name :

    unknown

    grid_mapping_name :

    lambert_conformal_conic

    standard_parallel :

    (38.5, 38.5)

    latitude_of_projection_origin :

    38.5

    longitude_of_central_meridian :

    262.5

    false_easting :

    0.0

    false_northing :

    0.0

    long_name :

    HRRR model grid projection

    array(None, dtype=object)

• Indexes: (0)
• Attributes: (12)

  GRIB_edition :

  2

  GRIB_centre :

  kwbc

  GRIB_centreDescription :

  US National Weather Service - NCEP

  GRIB_subCentre :

  0

  Conventions :

  CF-1.7

  institution :

  US National Weather Service - NCEP

  model :

  hrrr

  product :

  sfc

  description :

  High-Resolution Rapid Refresh - CONUS

  remote_grib :

  https://noaa-hrrr-bdp-pds.s3.amazonaws.com/hrrr.20210125/conus/hrrr.t06z.wrfsfcf00.grib2

  local_grib :

  C:\Users\blaylock\data\hrrr\20210125\subset_f7effd54__hrrr.t06z.wrfsfcf00.grib2

  searchString :

  TMP:2 m

ds.gribfile_projection

<xarray.DataArray 'gribfile_projection' ()>
array(None, dtype=object)
Coordinates:
    time               datetime64[ns] 2021-01-25T06:00:00
    step               timedelta64[ns] 00:00:00
    heightAboveGround  float64 2.0
    valid_time         datetime64[ns] 2021-01-25T06:00:00
Attributes: (12/17)
    crs_wkt:                        PROJCRS["unknown",BASEGEOGCRS["unknown",D...
    semi_major_axis:                6371229.0
    semi_minor_axis:                6371229.0
    inverse_flattening:             0.0
    reference_ellipsoid_name:       unknown
    longitude_of_prime_meridian:    0.0
    ...                             ...
    standard_parallel:              (38.5, 38.5)
    latitude_of_projection_origin:  38.5
    longitude_of_central_meridian:  262.5
    false_easting:                  0.0
    false_northing:                 0.0
    long_name:                      HRRR model grid projection

xarray.DataArray

'gribfile_projection'

• None

  array(None, dtype=object)

• Coordinates: (4)
  • time
    ()
    datetime64[ns]
    2021-01-25T06:00:00

    long_name :

    initial time of forecast

    standard_name :

    forecast_reference_time

    array('2021-01-25T06:00:00.000000000', dtype='datetime64[ns]')

  • step
    ()
    timedelta64[ns]
    00:00:00

    long_name :

    time since forecast_reference_time

    standard_name :

    forecast_period

    array(0, dtype='timedelta64[ns]')

  • heightAboveGround
    ()
    float64
    2.0

    long_name :

    height above the surface

    units :

    m

    positive :

    up

    standard_name :

    height

    array(2.)

  • valid_time
    ()
    datetime64[ns]
    2021-01-25T06:00:00

    standard_name :

    time

    long_name :

    time

    array('2021-01-25T06:00:00.000000000', dtype='datetime64[ns]')

• Indexes: (0)
• Attributes: (17)

  crs_wkt :

  PROJCRS["unknown",BASEGEOGCRS["unknown",DATUM["unknown",ELLIPSOID["unknown",6371229,0,LENGTHUNIT["metre",1,ID["EPSG",9001]]]],PRIMEM["Greenwich",0,ANGLEUNIT["degree",0.0174532925199433],ID["EPSG",8901]]],CONVERSION["unknown",METHOD["Lambert Conic Conformal (2SP)",ID["EPSG",9802]],PARAMETER["Latitude of false origin",38.5,ANGLEUNIT["degree",0.0174532925199433],ID["EPSG",8821]],PARAMETER["Longitude of false origin",262.5,ANGLEUNIT["degree",0.0174532925199433],ID["EPSG",8822]],PARAMETER["Latitude of 1st standard parallel",38.5,ANGLEUNIT["degree",0.0174532925199433],ID["EPSG",8823]],PARAMETER["Latitude of 2nd standard parallel",38.5,ANGLEUNIT["degree",0.0174532925199433],ID["EPSG",8824]],PARAMETER["Easting at false origin",0,LENGTHUNIT["metre",1],ID["EPSG",8826]],PARAMETER["Northing at false origin",0,LENGTHUNIT["metre",1],ID["EPSG",8827]]],CS[Cartesian,2],AXIS["(E)",east,ORDER[1],LENGTHUNIT["metre",1,ID["EPSG",9001]]],AXIS["(N)",north,ORDER[2],LENGTHUNIT["metre",1,ID["EPSG",9001]]]]

  semi_major_axis :

  6371229.0

  semi_minor_axis :

  6371229.0

  inverse_flattening :

  0.0

  reference_ellipsoid_name :

  unknown

  longitude_of_prime_meridian :

  0.0

  prime_meridian_name :

  Greenwich

  geographic_crs_name :

  unknown

  horizontal_datum_name :

  unknown

  projected_crs_name :

  unknown

  grid_mapping_name :

  lambert_conformal_conic

  standard_parallel :

  (38.5, 38.5)

  latitude_of_projection_origin :

  38.5

  longitude_of_central_meridian :

  262.5

  false_easting :

  0.0

  false_northing :

  0.0

  long_name :

  HRRR model grid projection