The NESDIS Blended Hydrometeorological Advected Layer Precipitable Water (ALPW) product provides water vapor values between predefined vertical layers (850 hPa to 700 hPa). For more details, see the ALPW Quick Guide PDF and Forsythe et al. (2015).

With the image looper, you can do the following:

• Step through images by
  • Clicking and dragging the circle on the current frame slide bar
  • Clicking the Start/Stop, Backward, or Forward buttons
  • Using the left-arrow ← key to step backward, right-arrow key → key to step forward, or Spacebar key to start and stop
• Zoom in by
  • Clicking the Left Click or Scroll with a mouse or touchpad to zoom in
  • Pressing the CTRL + Left Click, CMD + Left Click, or Scroll to reset
• Control refreshing images by
  • Clicking the Refresh button to reload the current imagery for the latest
  • Clicking the Disable Auto Refresh button to stop automatic loading new images
  • Clicking the Enable Auto Refresh button to allow automatic loading new images
• Show the location/coordinates by
  • Clicking the Show Location button to enable
  • Hovering the cursor on the image
  • Clicking the Hide Location button to disable
• Measure the distance and bearing in the "to" convention by
  • Clicking the Show Distance button to enable
  • Clicking and dragging the cursor on the image
  • Clicking the Hide Distance button to disable
• Annotate the image by
  • Clicking the Annotate button to display the control panel
  • Clicking the Finish button to stop annotating and erase current annotations
  • Clicking the Capture button to save everything displayed on the current image
  • NOTE: Annotations do not get saved when exporting to an MP4
• Save current imagery by
  • Clicking the Make MP4 button to save a video of the current imagery, enabled overlays, and zoom level
  • Clicking the Make GIF button to save an animated GIF of the current imagery, enabled overlays, and zoom level
• Control overlays by toggling overlay checkboxes and radio buttons