A Dynamic and Synoptic Study of a Wintertime Cyclone Using Geostationary and Polar Orbiting Satellite Data.
Abstract
A detailed study was carried out for a mid-latitude cyclone that occurred over the United States from 20 to 22 February 1976. Results indicated that the Laplacian of thickness advection and differential vorticity advection by the nondivergent part of the flow, together with surface frictional effects, were the dominate mechanisms throughout the life history of the cyclone. The storm underwent rapid development when the ascending motions, produced by these forcing functions, were nearly coincident and exhibited no vertical tilt in the lee of the Rocky Mountains. When the cyclone reached maturity, the strongest thermal and vorticity effects at mid-tropospheric levels advanced eastward ahead of the most intense frictional components at low levels. When the cyclone began to occlude, sinking motion was contributed by differential vorticity advection by the divergent part of the flow at low levels. This effect decreased the strong rising motion due to friction and eventually produced a shallow layer of subsidence that extended into the occluded system. Numerical computations of three dimensional trajectories illustrated the importance of low level moisture flow and the development of intense convective activity within the warm air sector of the cyclone. Comparisons of atmospheric trajectories with visible and infrared imagery from satellites showed good agreement with cloud fields and vertical motions.
Document Details
- Document Type
- Technical Report
- Publication Date
- Jun 01, 1979
- Accession Number
- ADA107986
Entities
People
- John Andrew Hall
Organizations
- Air Force Institute of Technology