title: GOES-East Full Disk domain realtime imagery does not fit actual data
body: <p>I'm trying to plot GOES-East full disk data using metpy, and Siphon to download the latest data from the THREDDS data server. However, after comparing my plots with the realtime imagery, ther seems to be a large difference.</p>
  <p>Below is my code:</p>
  <pre><code>import cartopy.crs as ccrs
  import cartopy.feature as cfeature
  import matplotlib.pyplot as plt
  import metpy.calc as mpcalc
  from metpy.plots.ctables import registry
  from metpy.plots import add_timestamp
  from metpy.units import units
  from siphon.catalog import TDSCatalog
  import xarray as xr
  import numpy as np
  from xarray.backends import NetCDF4DataStore
  from datetime import datetime, timedelta
  
  dt = datetime.utcnow().date()
  
  data = TDSCatalog(f'http://thredds.ucar.edu/thredds/catalog/satellite/goes/east/products/'
                   f'CloudAndMoistureImagery/FullDisk/Channel09/{dt:%Y%m%d}/catalog.xml')
  
  sat_dataset = data.datasets[0].remote_access(use_xarray = True)
  cmi = sat_dataset.metpy.parse_cf('Sectorized_CMI')
  x = cmi.coords['x'][:]
  y = cmi.coords['y'][:]
  timestamp = datetime.strptime(str(cmi.time.values.astype('datetime64[s]')), '%Y-%m-%dT%H:%M:%S')
  print(timestamp)
  
  vtime = timestamp.strftime('%Y-%m-%d %H%M%S')
      
  # Create the figure
  fig = plt.figure(figsize = [16, 10])
  ax = fig.add_subplot(1, 1, 1, projection = cmi.metpy.cartopy_crs)
  ax.set_extent([-80, -45, -50, -15], crs = ccrs.PlateCarree())
  ax.add_feature(cfeature.BORDERS.with_scale('50m'), edgecolor = 'black', linewidth = 1)
  ax.add_feature(cfeature.COASTLINE.with_scale('50m'), edgecolor = 'black', linewidth = 1)
  ax.add_feature(cfeature.STATES.with_scale('50m'), edgecolor = 'white', linewidth = 1)
  
  # Add mapping information
  ax.add_feature(cfeature.STATES)
  ax.add_feature(cfeature.BORDERS, linewidth=2)
  
  # Plot the image with our colormapping choices
  wv_norm, wv_cmap = registry.get_with_range('WVCIMSS_r', 193, 283)
  im = ax.imshow(cmi, extent=(x[0], x[-1], y[0], y[-1]), origin='upper',
                 cmap = wv_cmap, norm = wv_norm, transform = cmi.metpy.cartopy_crs)
  plt.colorbar(im, ticks = np.arange(193, 293, 10), ax = ax)
  
  plt.title(f'Vapor da Água em Níveis Médios [$K$] \nValid: {vtime} UTC', loc = 'left')
  
  plt.savefig(f'/mnt/c/Users/vitor/Desktop/WV_{vtime}.jpg', bbox_inches = 'tight')
  </code></pre>
  <p>Also below, is a comparison between the output from my code and the actual water vapor imagery from the CODNEXLAB website. I also looked at the metadata of the downloaded files and everything seems to be fine. Not sure if I'm doing something wrong here.</p>
  <p><a href="https://i.stack.imgur.com/WbtVq.jpg" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/WbtVq.jpg" alt="enter image description here" /></a>
  <a href="https://i.stack.imgur.com/ql5C5.jpg" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/ql5C5.jpg" alt="enter image description here" /></a></p>