Journal ArticleDOI
Shear Parameter Thresholds for Forecasting Tornadic Thunderstorms in Northern and Central California
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TLDR
A study of 39 nontornadic and 30 tornadic thunderstorms (composing 25 tornado events, as defined in the text) that occurred in northern and central California during the period 1990-94 shows that stratification of the stronger tornadic events (associated with F1 or greater tornadoes) on the basis of 0−1- and 0−6-km positive and bulk shear magnitudes is justified statistically as mentioned in this paper.Abstract:
A study of 39 nontornadic and 30 tornadic thunderstorms (composing 25 tornado “events,” as defined in the text) that occurred in northern and central California during the period 1990–94 shows that stratification of the stronger tornadic events (associated with F1 or greater tornadoes) on the basis of 0–1- and 0–6-km positive and bulk shear magnitudes is justified statistically. Shear values for the weaker F0 events could not be distinguished statistically from the “background” values calculated for the nontornadic (null) thunderstorm events observed during the period. Shear magnitudes calculated for the F1/F2 events suggest that these tornadoes had developed in an environment supportive of supercell convection. Hindcasting the tornado events based upon shear thresholds produced a high probability of detection (POD) and low false alarm ratio (FAR), particularly for the stronger (F1/F2) events. Although the current sample size is limited and the conclusions drawn from it should be considered preli...read more
Citations
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References
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Journal ArticleDOI
The Dependence of Numerically Simulated Convective Storms on Vertical Wind Shear and Buoyancy
TL;DR: In this paper, the effects of vertical wind shear and buoyancy on convective storm structure and evolution were investigated with the use of a three-dimensional numerical cloud model, by varying the magnitude of buoyant energy and one-directional vertical shear over a wide range of environmental conditions associated with severe storms.
Journal ArticleDOI
Severe Local Storms Forecasting
TL;DR: In this paper, the authors present a review of the current knowledge of severe local storms as it relates to the development of new applications for forecasting of local storms. But, they focus on the physical understanding of processes taking place on the storm scale and thus allow forecasters to become less dependent on empirical relationships.
Book
Probability and statistics for engineers
TL;DR: Within the presentation of topics and applications the authors continually develop students' intuition for collecting their own real data, analyzing it with the latest graphical tools, and interpreting the results with a goal of improving quality control and problem-solving process.
Journal ArticleDOI
On the Rotation and Propagation of Simulated Supercell Thunderstorms
Richard Rotunno,Joseph B. Klemp +1 more
TL;DR: In this paper, the rotation and propagation of the supercell-like convection produced by a three-dimensional cloud model were examined in terms of the conservation of equivalent potential vorticity and V. Bjerknes' first circulation theorem.