Results 141 to 150 of about 1,271 (165)

Synoptic aspects of Antarctic mesocyclones

Journal of Geophysical Research: Atmospheres, 1993
The characteristic regimes (formation and dissipation areas, tracks) and synoptic environments of cold air mesocyclones over Antarctic and Subantarctic latitudes are determined for the contrasting winters (June, July, and August) of 1988 and 1989. Defense Meteorological Satellite Program (DMSP) thermal infrared (IR) imagery is used in conjunction with ...
Andrew M. Carleton, Mark Fitch
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Mesocyclone Detection and Classification Algorithm.

1983
Abstract : A proposed four-dimensional algorithm for automated detection of mesocyclones employs resolution-dependent thresholds of rotational velocity and shear. This algorithm incorporates complementary features of earlier techniques suggested by Hennington and Burgess and by Forsyth, Bjerkaas and Petrocchi.
null Jr, Ralph J. Donaldson, James G. Wieler   +2 more
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A Variational Method for Analyzing Vortex Flows in Radar-Scanned Tornadic Mesocyclones. Part IV: Applications to the 20 May 2013 Oklahoma Tornadic Mesocyclone

Journal of the Atmospheric Sciences, 2022
Abstract The variational method for vortex flow (VF) analyses, called VF-Var (formulated in Part I), is applied to the 20 May 2013 Newcastle–Moore tornadic mesocyclone observed from the operational KTLX radar and an experimental phased-array radar. The dual-Doppler-analyzed VF field reveals the following features: The axisymmetric part of the VF is a ...
Qin Xu, Li Wei, Kang Nai
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Mesocyclone Evolution and Tornadogenesis: Some Observations

Monthly Weather Review, 1978
Abstract Updraft mesocyclones in tornado-producing thunderstorms form along convergent and cyclonically sheared boundaries that separate inflow air entering forward and rear storm quadrants. Maximum tangential flow resides in girding wind bands, averaging usually less than 3 km in radius (depending upon the development stage), that strengthen near ...
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On the Environments of Tornadic and Nontornadic Mesocyclones

Weather and Forecasting, 1994
Abstract The authors investigated differences in the environments associated with tornadic and nontornadic mesocyclones are investigated using proximity soundings. Questions about the definition of proximity are raised. As the environments of severe storms with high spatial and temporal resolution are observed, the operational meaning of proximity ...
Harold E. Brooks, Charles A. Doswell, Jeremy Cooper   +2 more
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Mesocyclone Passes over NSSL Surface Station

Bulletin of the American Meteorological Society, 1982
An apparent mesocyclone passed directly over a surface station that was equipped with both digital and strip chart recorders near Criner, Okla. Peak gusts were 18 m s−1 (35 kt); within 3 min the surface wind changed from strong southeasterly to strong westerly. The pressure dropped 5 mb in 52 min and recovered 4 mb in 6 min.
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Automatic Detection of Mesocyclonic Shear with Doppler Radar

Journal of Atmospheric and Oceanic Technology, 1985
Abstract A region of high wind shear always accompanies large intense tornadoes. Such shear is readily measured by Doppler radar and thus can be used to identify regions in storms where tornadoes are likely to form. An algorithm developed at the National Severe Storms Laboratory uses decision thresholds to discriminate between mesocyclone shear and ...
D. S. Zrnić, D. W. Burgess, L. D. Hennington   +2 more
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Intense mesocyclones in the Black Sea region

Russian Meteorology and Hydrology, 2016
The statistical study of intense mesoscale cyclones formed in the Black Sea region in 1979-2013 is carried out using the surface wind data of the RegCM climate model. Such cyclone parameters as intensity, lifetime, area, height, and trajectories over the sea as well as the place and time of origin are considered.
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Automatic Tornado Prediction with an Improved Mesocyclone-Detection Algorithm

Weather and Forecasting, 1992
Abstract A new and improved algorithm for automatic mesocyclone detection is presented and tested on 23 mesocyclonic storms. A small false-alarm rate (4%) and high probability of detection (83%) are achieved for mesocyclone classification. A unique innovation of the algorithm is the automatic assessment of mesocyclone tornado potential.
Paul R. Desrochers, Ralph J. Donaldson
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Observed Relationship between Tornado Intensity and Pretornadic Mesocyclone Characteristics

Weather and Forecasting, 2020
AbstractIn a previous study, idealized model simulations of supercell thunderstorms were used to demonstrate support of the hypothesis that wide, intense tornadoes should form more readily out of wide, rotating updrafts. Observational data were used herein to test the generality of this hypothesis, especially to tornado-bearing convective morphologies ...
Michael F. Sessa, Robert J. Trapp
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