Mesoscale Vertical Structure of an Explosive Oceanic Cyclone
Abstract
The mesoscale vertical structure of an explosively deepening oceanic cyclone on 19-20 January 1989 during the Experiment on Rapidly Intensifying Cyclones over the Atlantic (ERICA) was studied. Hand analyses of height, temperature, and dew point, and cross-sections of theta and theta sub e were prepared using aircraft and sounding data through the warm-frontal region in order to document the vertical structure. The results showed that the initial disturbance formed under a region of strong upper-level confluence between a southern jet streak and an approaching upper-level short-wave from the northwest. Upper-level frontogenesis associated with the confluent flow was strong enough to produce tropopause folding and stratospheric extrusion as low as 700 mb about 750 km upstream from the surface low prior to rapid deepening. The mesoscale analyses during the initial occlusion phase showed the upper-level temperature and moisture patterns spiraling around the low center with strong warm air advection occurring under a pocket of cold air, aloft, producing significant convective instability. The cross-sections of theta sub e throughout the rapid deepening period showed unstable conditions, which suggests that moist potential instability in the warm frontal region was a factor in the rapid development of this storm.
Document Details
- Document Type
- Technical Report
- Publication Date
- Jun 01, 1991
- Accession Number
- ADA245927
Entities
People
- Elizabeth B. Gardner
Organizations
- Naval Postgraduate School