The 8th Conference on Aviation, Range, and Aerospace Meteorology

12.6
HOW CAN WE USE AND DEPICT VARIABILITY OF CLOUDS IN ICING FORECASTS?

Marcia K. Politovich, Boulder, CO

Real clouds contain considerable vertical and horizontal variability in their icing-related characteristics. How can we depict such variation more realistically in icing forecasts, while retaining a user-friendly format?

Applying knowledge of cloud structure will help provide a more realistic forecast presentation. Detailed measurements in clouds were obtained by instrumented aircraft in northeastern Colorado during the Winter Icing and Storms Project (WISP) and in the Cleveland area during the Supercooled Large Drop Research Program (SLDRP). These measurements, which represent two vastly different weather regimes, were compiled and combined with basic cloud physics to derive guidance on expected variability in temperature, liquid water content, droplet size, and other parameters. Dependence of variability on height above cloud base (or below cloud top), temperature, presence or absence of ice crystals, and turbulence will be examined. Local rawinsonde data will be used when available to relate the variations to stability. Suggestions for and examples of depictions of variability into forecasts are included

The 8th Conference on Aviation, Range, and Aerospace Meteorology