Download or read book The Life Cycle of Thunderstorm Gust Fronts as Viewed with Doppler Radar and Rawinsonde Data written by Roger M. Wakimoto and published by . This book was released on 1982 with total page 23 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Thunderstorms Thunderstorm morphology and dynamics written by and published by . This book was released on 1981 with total page 622 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Thunderstorm Gust Fronts written by United States. Federal Aviation Administration. Systems Research and Development Service and published by . This book was released on 1978 with total page 122 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Investigations of Thunderstorm Gust Fronts from Project NIMROD Data written by Roger M. Wakimoto and published by . This book was released on 1981 with total page 258 pages. Available in PDF, EPUB and Kindle. Book excerpt: This dissertation investigates the thunderstorm gust front with the aid of Project NIMROD data. The main goal is to present the time dependent solution of the gust front. RHI and VAD cross sections of reflectivity and Doppler velocity were constructed for different three minute radar scans to determine the vertical structure. These analyses revealed that the life cycle of the gust front could be divided into four stages: 1) the formative stage; 2) the early mature stage; 3) the late mature stage; and 4) the dissipation stage. A new finding was a horizontal roll detected in the reflectivity patterns during stages II and III. This phenomenon was called a "precipitation roll." Rawinsonde launchings revealed the thermodynamic structure of the gust front. The cold air layer was found to correspond closely to the observed surface pressure rise. Calculations confirmed that the collision of two fluids produced nonhydrostatic pressure forces at the leading edge of the outflow. A dry, cool layer at the top of the gust front was a result of the low level outflow that was lifted vertically at the frontal boundary and advected back by the circulation within the bead of the gust front. The equation for the propagation speed of a density current was confirmed to accurately predict the movement of the gust front, thus disproving the theory that the gust front is an advecting phenomenon. Comparisons are made between the gust front and the "downburst" to emphasize their different nature.
Download or read book Thunderstorms a Social Scientific Technological Documentary Thunderstorm morphology and dynamics written by and published by . This book was released on 1982 with total page 626 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Thunderstorm Morphology and Dynamics written by and published by . This book was released on 1982 with total page 632 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Gust Front Analytical Study written by R. C. Goff and published by . This book was released on 1977 with total page 142 pages. Available in PDF, EPUB and Kindle. Book excerpt: Strong wind changes and turbulence encountered by aircraft arriving or departing an airport constitute hazards to safe flight. Most serious encounters are thunderstorm outflow related. The gust front structure as observed by Doppler radar, standard weather radar, a 461 m meteorologically instrumented tower, aircraft and other observations is presented. Gust front evolution as observed with a severe thunderstorm is shown. Turbulence and multiple surges are discussed. (Author).
Download or read book The Thunderstorm written by United States. Weather Bureau and published by . This book was released on 1949 with total page 308 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Severe Local Storms written by David Atlas and published by Springer. This book was released on 2016-06-28 with total page 258 pages. Available in PDF, EPUB and Kindle. Book excerpt: The objectives of the American Meteorological Society are "the development and dissemination of knowledge of meteorology in all its phases and applications, and the advancement of its professional ideals." The organization of the Society took place in affiliation with the American Association for the Advancement of Science at Saint Louis, Missouri, December 29, 1919, and its incorporation, at Washington, D. C., January 21, 1920. The work of the Society is carried on by the Bulletin, the Journal, and Meteorological Monographs, by papers and discussions at meetings of the Society, through the offices of the Secretary and the Executive Secretary, and by correspondence. All of the Americas are represented in the membership of the Society as well as many foreign countries.
Download or read book Numerical Simulation of Thunderstorm Gust Fronts written by Keith L. Seitter and published by . This book was released on 1983 with total page 40 pages. Available in PDF, EPUB and Kindle. Book excerpt: The thunderstorm gust front is an important feature for both the maintenance and initiation of storms. Previous studies have shown that the thunderstorm outflow producing the gust front can be treated as an atmospheric density current to a good approximation. In this study, a new version of the density current speed equation, based on the surface pressure rise, is derived. This equation is shown to give much better results than other commonly used forms when applied to twenty previously reported gust front observations. A two-dimensional numerical model is used to investigate the dynamics of atmospheric density currents. Simulations with this model show the effects of the environmental wind relative to the storm and the wind shear on the propagation of the gust front and the depth of the thunderstorm outflow. The results of these simulations are discussed in terms of the conditions necessary for the gust front to remain in a position that is beneficial for the maintenance of the storm. Moist processes are included in the model and simulations are made to investigate atmospheric density current propagation through a moist atmosphere. The lifting that occurs during gust front passage is calculated and it is found that even when this lifting is sufficient to bring moist parcels above their level of free convection; deep convection is prohibited by other aspects of the circulation. The generation of an arc cloud by the gust front is found to result in a less intense and slower gust front compared to an outflow that did not produce an arc cloud. This result is interpreted in terms of the gust front speed equation based on the surface pressure rise.
Download or read book Life cycle of a Summer Storm from Radar Records written by Holtz, C. D. (Clifford Donald) and published by Macdonald Physics Laboratory ; Stormy Weather Group. This book was released on 1968 with total page 55 pages. Available in PDF, EPUB and Kindle. Book excerpt: Using radar, the area, the volume and the mass of precipitation in a thunderstorm have been studied as well as their distributions with intensity, height and time. A three-dimensional model, derived statistically, indicates that at each moment during the life-cycle the general spatial shape and intensity structure of the radar-observed storm is related to the total mass of precipitation aloft. (Author).
Download or read book A Thunderstorm Gust Front Detection System Part I System Operation and Significant Case Studies Part II Statistical Results written by and published by . This book was released on 1979 with total page 147 pages. Available in PDF, EPUB and Kindle. Book excerpt: The Dulles International Airport wind and wind shear detection system recorded more than 160 events from November 1976 through March 1978. Eighty-two percent of 113 significant events occurred in conjunction with thunderstorms, squall-lines and frontal passages. The chief source of false alarms for anemometers was boundary layer disturbances representing 10% of the total; while gravity shear waves related to the 500mb winds caused the most false alarms for pressure sensors (4% of the total). Using complementary arrays of wind and pressure sensors, total system false alarms can be greatly reduced. These data demonstrate the importance of stable surface layers in determining how well surface temperature and wind measurements represent flow at higher levels and explain underestimates of system severity. Moreover, because we demonstrate the value of wind vector information and since temperature is a scaler quantity, there seems little operational value in using temperature sensors as part of a detection system. Conversely, pressure sensors will not reliably detect relatively thin outflows (100-200 M thick) occurring at a distance from downflows having small dimensions. Again, the wind and pressure sensors combine to provide a total system offering good reliability for detection of thunderstorm outflows. The results suggest an array configuration (composed of wind and pressure jump sensors) for use in airport warning systems. This configuration extending about 10km from the airport provides a warning for Thunderstorm gust-fronts.
Download or read book Thunderstorm Gust Fronts written by and published by . This book was released on 1978 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Thunderstorm Gust Fonts Observations and Modeling written by J. T. Lee and published by . This book was released on 1978 with total page 114 pages. Available in PDF, EPUB and Kindle. Book excerpt: Gust front structures as observed and as modeled are reviewed and a mean model presented. Integrated observations from the 461 m meteorologically instrumented tower at Oklahoma City, OK, aircraft, weather satellites and Doppler radar are compared to one and two-dimensional models to provide a better understanding of the gust front. In the mean, updrafts of 3 m/sec accompany the gust front's approach. Horizontal wind shears are 8 m/sec per km. Gust front cases in 1976 and 1977 are presented along with a data log of tower observations. Aircraft observations during gust front flights are also presented. (Author).
Download or read book Monthly Weather Review written by and published by . This book was released on 2003 with total page 1164 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Thunderstorm gust fronts written by and published by . This book was released on 1978 with total page 100 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Synoptic dynamic Meteorology in Midlatitudes Observations and theory of weather systems written by Howard B. Bluestein and published by Taylor & Francis. This book was released on 1992 with total page 622 pages. Available in PDF, EPUB and Kindle. Book excerpt: Synoptic meteorology, the study of large-scale weather systems and forecasting using observation, and dynamic meteorology, the study of the laws of physics involved in air movement, are treated in this major new text in two volumes. The author, a meteorologist noted for his research on tornadoes and severe storms, based his work on material he has taught for the past 14 years at the University of Oklahoma. There are no modern texts on the topic. Volume II covers the formation, motion and climatology of extratropical weather systems in the context of the quasigeostrophic theory and "IPV" thinking, the formation and structure of fronts and jets, applications of semigeostrophic theory, and the observed structure and dynamics of precipitation systems in midlatitudes.
