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Recent work established strong links between storm updraft width and the tornado intensity, suggesting that updraft width could be used to gauge potential tornado intensity. It was also posited that overshooting top area (OTA) could be used as an analog for updraft width and, thus, as a means to assess potential tornado intensity in observed storms. The implementation of new high‐resolution GOES‐R series satellites presents a unique opportunity to investigate these findings in severe weather observations. Herein, a method using GOES‐16 longwave infrared satellite data to quantify OTA of tornadic storms is explored. A comparison between observed tornado strength and OTA yields a strong correlation (R2 = 0.54). These results show the potential of these quantifications to be used with real‐time observations of tornadic storms, irrespective of storm mode, seasonality, or geographic location, allowing forecasters to determine which storms pose the highest risk to life and property. Plain Language Summary: Identifying storms capable of producing strong tornadoes remains a focus of severe weather research due to their significant impacts to life and property. Recent advancements in satellite observations present new opportunities to develop methods for identifying these storms. Using satellite imagery of the top of severe thunderstorms, a strong relationship is identified between the size of the imprint of the storm's updraft and the strength of the tornado that may develop within it. This information might be used by meteorologists to identify storms with the highest potential to produce violent tornadoes and to communicate better the risk posed by them to the public. Key Points: There is a strong relationship of overshooting top area to tornado EF rating in tornadic thunderstormsThis relationship holds for different storm morphologies, seasons, and geographic locationsThe overshooting top area method shows promise in operational applications [ABSTRACT FROM AUTHOR]

In the United States, visual observations of tornadoes and/or the existence of tornado damage currently provide the sole evidence of tornadogenesis in association with a mesocyclone or other radar-detected storm-scale vortex. The severity of the tornado damage is currently the only means of estimating the intensity of tornadoes, radar detected or otherwise. The limitations of the damage-based record of tornado occurrence and intensity are well known and motivated this research. Weather Surveillance Radar-1988 Doppler (WSR-88D) measurements of the translating tornadic flow were compared with (semi-) coordinated measurements obtained near the surface with mobile radar. On the basis of a small yet fairly broad sample of tornadoes, high linear correlation was found between the vortex intensity (rotation plus translation) quantified using WSR-88D data and that quantified using Doppler on Wheels data. The possible effects of Doppler radar sampling on these results were explored through experiments with a simple vortex model. These experiments argued that the likelihood is high that a tornado would be sampled in a favorable way during at least one radar scan. Hence, the suggestion from this work is that WSR-88Ds (or similar operational radars) can potentially be used in isolation to estimate low-level tornado intensity. The proposed estimation is by way of a linear regression model, and application of this model is relevant only once a tornado is already confirmed. [ABSTRACT FROM AUTHOR]

Investigates the precipitation processes of a winter event that occurred on March 8-9, 1994 in northern Oklahoma. Examination of the synoptic scale and mesoscale; Overview of structure and evolution revealed by radar; Description of the elevated convective element.

Recent and past observations of a central downdraft within a mesocyclone have been misinterpreted as evidence of vortex breakdown on the mesocyclone scale. In this note, the literature is reviewed and model examples are provided in order to demonstrate that the mesocyclone dynamics likely precludes mesocyclonic vortex breakdown. It is shown that an adverse vertical pressure gradient, induced by vertical vorticity that decreases in intensity with height, leads to the formation of a central downdraft, hence, two-celled vortex, in absence of vortex breakdown. Two-celled mesocyclones, then, may form when low-level vertical vorticity, generated by the vertical tilting of horizontal baroclinic vorticity, exceeds that generated at midlevels. Tornadogenesis occurs in a two-celled mesocyclonic vortex if an instability to which the vortex is susceptible is released. [ABSTRACT FROM AUTHOR]

The spherical geometry of weather radar scans results in a data distribution wherein datapoint separation in one coordinate direction and/or in one part of the analysis domain can differ widely from that in another. Objective analysis of the nonuniform radar data to a uniform Cartesian grid is desirable for many diagnostic purposes. For the benefit of the diagnostic data analyst as well as of users of these analyses, the authors evaluate properties of techniques typically used for such objective analysis. This is done partly through theoretical consideration of the properties of the schemes, but mostly by empirical testing. In terms of preservation of the phase and amplitude of the input data, predictability of the degree of smoothing and filtering, and relative insensitivity to input data unsteadiness or spatial characteristic, the isotropic Gaussian or Barnes-type weight function with constant smoothing parameter appears to be the most desirable of the schemes considered. Modification of this scheme so that the weight function varies spatially, with the datapoint spacing, results in an improved analysis, according to some commonly used measures of error. Interpretation of analyses based on such a modified scheme can be affected, however. For example, analyses of unsteady input fields suffer from a convolution of the temporal evolution of the data with spatial variations of the weight function. As a consequence, unambiguous assessment of physical evolution is precluded. [ABSTRACT FROM AUTHOR]

Determines the condition under which a tornado is or is not preceded by a dynamic pipe effect (DPE) using a numerical model. Process of DPE; Simulation of the genesis of tornado-like vortices within a rotating updraft; Types of genesis; Types of tornadoes and other convective vortices.

Presents a tornadogenesis model which allows the isolation and control of thunderstorm features hypothesized to have a role in tornadogenesis. Description of numerical and pseudostorm modeling approach; Experiments with ambient vertical vorticity and pseudostorm experiment.

Winter storms and their prediction are of increasing importance throughout the region of the United States with the fastest growing population, the Intermountain West. Such storms can produce heavy orographic snowfall, lake-effect snowbands, and even lightning. Unfortunately, precipitation forecast skill is lower over the Intermountain West thanother regions of the country because of the complex topography, the lack or limited utility of upstream and in situ data, and insufficient understanding of storm and precipitation processes. The Intermountain Precipitation Experiment (IPEX) is a research program designed to improve the understanding, analysis, and prediction of precipitation over the complex topography of the Intermountain West. The field phase of this research program was held in northern Utah in February 2000. During this time, seven storms were observed, including the heaviest snowfall to strike the Wasatch Mountains in two years, a tornadic bow echo associated with a strong cold front, a mesoscale snowband in Tooele Valley, and three other storms with locally heavy orographic snowfall and complex mesoscale circulations. Some of these storms were electrified and produced lightning. This paper reviews the weather of the Intermountain West, describes the experimental setup and the outreach activities of IPEX, and presents preliminary results from the field phase. Finally, lessons learned in planning and executing this field program are discussed. [ABSTRACT FROM AUTHOR]

Presents a vision guided robotic system for an autonomous car disassembly process. Use of an active stereo camera system as vision sensor; Description of a combination of gray value and contour-based object recognition and a position measurement approach with implicit detection; Integration of a stereo vision system, a force-torque sensor, a task planning module and a special unscrewing tool into a demonstrator.