WXlog/20120625 Electrification


The RHI scan shown below was conducted through a thunderstorm located ~40 km northwest of the CSU-CHILL radar during the DC3 project. The presence of a strong, vertically oriented electric field in the upper portion of the storm rotates the long axis of planar ice crystals towards a vertical orientation. The opposite (horizontal) preferential particle orientation exists near the ground in the high reflectivity core where large concentrations of oblate rain drops occur. This state of affairs causes the sense of the change of differential propagation phase shift with range to be reversed at upper vs. lower heights in the storm.