Topic
Wake low
About: Wake low is a research topic. Over the lifetime, 89 publications have been published within this topic receiving 4371 citations.
Papers published on a yearly basis
Papers
TL;DR: In this article, the mechanics of long-lived, line-oriented, precipitating cumulus convection (squall lines) using two-and three-dimensional numerical models of moist convection are studied.
Abstract: We study herein the mechanics of long-lived, line-oriented, precipitating cumulus convection (squall lines) using two- and three-dimensional numerical models of moist convection. These models, used in juxtaposition, enable us to address the important theoretical issue of whether a squall line is a system of special, long-lived cells, or whether it is a long-lived system of ordinary, short-lived cells. Our review of the observational literature indicates that the latter is the most consistent paradigm for the vast majority of cases but, on occasion, a squall line may be composed of essentially steady, supercell thunderstorms. The numerical experiments presented herein show that either type of squall line may develop from an initial line-like disturbance depending on the magnitude and orientation of the environmental shear with respect to the line. With shallow shear, oriented perpendicular to the line, a long-lived line evolves containing individually short-lived cells. Our analysis of this type o...
1,423 citations
TL;DR: In this paper, the authors describe the two different kinds of downdraft air frequently observed to the rear of some low-latitude squall lines at low levels, and the lowest layer is hypothesized to be the product of convective-scale saturated downdavs and the drier air is the result of mesoscale unsaturated downdvings as described by Zipser.
Abstract: This paper describes the two different kinds of downdraft air frequently observed to the rear of some squall lines at low levels. The primary data source is measurements taken during aircraft penetrations of certain low-latitude squall lines; they are supplemented by satellite data, radar data, surface meteorological data, and soundings ahead of and behind the squall lines. A shallow layer of cool, near-saturated air occupies the lowest few hundred meters and is separated by a marked stable layer from a deep layer of highly unsaturated air. The lowest layer is hypothesized to be the product of convective-scale saturated downdrafts, and the drier air is shown to be the result of mesoscale unsaturated downdrafts as described by Zipser (1969). Over a warm ocean, there is a large latent and sensible heat flux from the surface into the lowest layer, which rapidly becomes a new mixed layer and incorporates the drier air from above by entrainment. Mesoscale sinking in the post-squall region is shown to ...
586 citations
TL;DR: The utility of color displays of Doppler-radar data in revealing real-time kinematic information has been demonstrated in past studies, especially for extratropical cyclones and severe thunderstorms as discussed by the authors.
Abstract: The utility of color displays of Doppler-radar data in revealing real-time kinematic information has been demonstrated in past studies, especially for extratropical cyclones and severe thunderstorms. Such displays can also indicate aspects of the circulation within a certain type of mesoscale convective system—the squall line with trailing “stratiform” rain. Displays from a single Doppler radar collected in two squall-line storms observed during the Oklahoma-Kansas PRE-STORM project conducted in May and June 1985 reveal mesoscale-flow patterns in the stratiform rain region of the squall line, such as front-to-rear storm-relative flow at upper levels, a subsiding storm-relative rear inflow at middle and low levels, and low-level divergent flow associated with strong mesoscale subsidence. “Dual-Doppler” analysis further illustrates these mesoscale-flow features and, in addition, shows the structure of the convective region within the squall line and a mesoscale vortex in the “stratiform” region tra...
417 citations
TL;DR: In this paper, the surface pressure features associated with a midlatitude squall line with trailing stratiform precipitation are investigated, including a pre-squall mesolow, a squall mesohigh and a wake low.
Abstract: Observations from the Oklahoma–Kansas Preliminary Regional Experiment for STORM-Central (OK PRE-STORM) have been used to document the surface pressure features accompanying an intense midlatitude squall line with trailing stratiform precipitation. Three well-known features are observed: a pre-squall mesolow, a squall mesohigh and a wake low. Particular attention is given to the wake low, its life cycle and association with the trailing stratiform portion of the squall line. During the formative stage, the pressure field to the rear of the squall line mesohigh is relatively flat with only weak stratiform precipitation present. As the squall line enters the developing-to-mature stages, a pronounced wake low appears at the back edge of the surface stratiform precipitation area. The squall line at this time is characterized by a strong rear-inflow jet, descending from the upper troposphere, as far as 500 km behind the leading convective line, to the lower troposphere just behind the line. The trailin...
267 citations
TL;DR: In this paper, a system of synoptic analysis on a mesometeorological scale has been developed through the combined use of space and time sections applied to all regular and special stations in an area 500 by 900 mi.
Abstract: A system of synoptic analysis on a mesometeorological scale has been developed through the combined use of space and time sections applied to all regular and special stations in an area 500 by 900 mi. in the Central United States. Two periods of development of large thunderstorm areas are analyzed. In both of these periods tornadoes occurred. The synoptic model of a squall line in this scale involves three principal features of the pressure field—the pressure surge, the thunderstorm high and the wake depression. Another feature, called the tornado cyclone, accompanies tornado funnels. Divergence values of 10 to 60 · 10 −5 sec −1 over areas of 100 to 10,000 sq. mi. are measured. The mesosynoptic disturbances greatly influence the situation as viewed on the regular synoptic scale, which is about 10 times the meso-scale, and make conventional analysis hopelessly difficult. DOI: 10.1111/j.2153-3490.1955.tb01181.x
158 citations
Related Topics (5)
Performance Metrics
| Year | Papers |
|---|---|
| 2018 | 1 |
| 2017 | 2 |
| 2016 | 2 |
| 2015 | 5 |
| 2014 | 4 |
| 2013 | 5 |