Accession Number:

ADA610084

Title:

Generalized Analysis of Orographically Modified Winds and Precipitation Observed by Airborne Doppler Radar During Phases I & II of COAST

Descriptive Note:

Annual rept.

Corporate Author:

NATIONAL OCEANIC AND ATMOSPHERIC ADMINISTRATION NORMAN OK NATIONAL SEVERE STORMS LAB

Report Date:

2000-09-30

Pagination or Media Count:

4.0

Abstract:

The long-term goal is accurate short-range forecasts 0-48 h lead of significant mesoscale weather disturbances, especially high winds and heavy precipitation, that can accompany landfalling cool-season frontal systems and intervening periods of steadier flow impinging upon steep coastal terrain. This research seeks to achieve a quantitative, dynamically-based understanding of the perturbed airflow and precipitation fields associated with both quasi-steady onshore flows oceanic frontal systems and steady onshore flows encountering steep coastal terrain. Moreover, by analyzing observations adjacent to topographic barriers of varying geometry and complexity, we aim to identify reproducible phenomena and more general principles governing these interactions. While the capability of mesoscale numerical forecast models to address these problems is still being tested, such models clearly offer great potential for capitalizing upon this improved understanding if critical processes are identified and appropriate model physicsparameterizations are put into place. Emphasis is thus placed upon collection and analysis of specialized observations needed to validate, test and improve mesoscale models. Of particular interest are those processes leading to development of high winds and heavy precipitation over coastal waters, as well as modulation of airflow and precipitation over the adjacent sloped terrain. Data obtained through pilot observational efforts are also evaluated critically to focus hypotheses and improve observational strategies applied in subsequent field programs.

Subject Categories:

  • Meteorology
  • Geography
  • Active and Passive Radar Detection and Equipment

Distribution Statement:

APPROVED FOR PUBLIC RELEASE