Coastal Frontogenesis and Associated Severe Weather on 13 March 1986 (GALE IOP 13)
Abstract
An investigation of the mesoscale structure of coastal frontogenesis and associated severe weather on 13 March 1986 occurring in North Carolina was conducted. A case study focused on the development of a coastal front and subsequent occurrence of severe weather during the GALE (Genesis of Atlantic Lows Experiment) field project. The GALE surface and upper-air data network was used to describe the kinematic and thermodynamic processes in the vicinity of the coastal front and severe weather. The presence of a mesoscale circulation conducive to frontogenesis was found from surface analyses of standard operational and special GALE data plus time-averaged divergence fields. The mesoscale divergence patterns plus numerical calculations of frontogenesis implied the coastal front developed in discontinuous sections as several convergence lines apparently formed independent of each other. The three- dimensional atmospheric structure in the vicinity of the frontogenesis was examined by means of divergence fields. Vertical velocities were calculated using the kinematic, thermodynamic, and quasi-geostrophic methods. Three types of mesoscale rainbands were observed and analyzed using 15-minute digitized radar data. Warm-sector rainbands developed south of the coastal front while convective cold-frontal and narrow cold-frontal rainbands developed along the coastal front as it moved southeast as a cold front. Severe weather mechanisms were investigated to determine why this unusual weather occurred during a late winter coastal front event. Analysis of the K-index, Lifted Index, and dynamic ingredients (thermal, moisture, and wind patterns) conducive to severe weather indicated conditions did in fact exist for severe weather to form.
Document Details
- Document Type
- Technical Report
- Publication Date
- Jan 01, 1989
- Accession Number
- ADA217708
Entities
People
- William H. Bauman Iii
Organizations
- Air Force Institute of Technology