Enroute Icing

### Produced by The COMET® Program

### Step 1: Diagnosing Locations of Icing » Satellite Data » Water Vapor

Water vapor imagery lets you determine the water vapor content in an atmospheric column, particularly in the mid to upper troposphere. You can see atmospheric flow through the movement of water vapor features and therefore identify active weather and moist regions with icing potential.

The various colors depict different characteristics:

- Drier areas have orange to red shading
- Moister areas have dark gray to white shading
- Colder, moist areas have purple and blue shading, and may contain icing
- Sharp color gradients from grey/white/purple/blue (moist or moistening, neutral to upward motion) to orange and red (dry or drying, sinking motion) show the location of the jet stream

Here’s the water vapor animation from approximately 00 to 1302 UTC 26 Feb. View it, making a mental note of areas that might be conducive to icing, and moving features in the atmospheric flow that may generate clouds and precipitation.