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Evan Ruzanski, V. Chandrasekar, and Yanting Wang

1. Introduction The term “nowcasting” refers to short-term (0–6 h or less) forecasting. Nowcasts of high-impact weather events, such as flood-producing rains and hail, can be made with sufficient lead time accuracy and spatial specificity within this time frame such that appropriate actions can be taken to effectively mitigate the loss of life and property. Thus, the term nowcasting emphasizes specificity and the short time nature of a weather event forecast ( Browning 1982 ). In current

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Sandy Dance, Elizabeth Ebert, and David Scurrah

1. Introduction Providing public warnings of impending thunderstorms is an important role of weather services. By observing the motion and evolution of thunderstorms using radar data, forecasters can reasonably predict the location and severity of thunderstorms up to 1 h into the future. This is an example of what is widely known as “nowcasting.” To help objectify and automate the nowcasting process, many radar-based systems have been developed in recent years. Among these are Thunderstorm

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James W. Wilson, Yerong Feng, Min Chen, and Rita D. Roberts

1. Introduction The purpose of this paper is threefold. The first intent is to provide insights into the convective storm nowcasting challenges specific to Beijing, China. The second intent is to present the results of nowcasts made using a diverse variety of state-of-the-art nowcasting systems during the 2008 Beijing Summer Olympic Games. The third is to provide comments on the present status of nowcasting convective storms, and possible future directions based on these experiences. A

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Laura X. Huang, George A. Isaac, and Grant Sheng

1. Introduction Nowcasting is short-period weather forecasting concerned with current weather conditions and the changes over the next few tens of minutes to the ensuing 6 h. In contrast to the familiar synoptic weather forecast (beyond 6 h), nowcasting is also highly location specific and requires data of very high spatial and temporal resolution to produce accurate forecasts. The primary aim of nowcasting is to predict significant weather events with high specificity as to their onset

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J. M. Pearson and R. D. Sharman

1. Introduction This is the continuation of a two-part paper that describes a method for developing automated (strategic) forecasts and (tactical) nowcasts of energy dissipation rate to the one-third power (EDR) for aviation turbulence applications. Part I provided a description of the forecast method along with statistical-performance results from comparisons with observations ( Sharman and Pearson 2017 ). The turbulence-forecasting technique is an extension of the Graphical Turbulence

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Yiwen Mao and Asgeir Sorteberg

1. Introduction The methods that are primarily used for nowcasting precipitation over a short period of time (e.g., <6 h) can be classified into two categories: 1) methods based on numerical weather prediction (NWP) models, and 2) methods based on extrapolating radar echoes ( Dixon and Wiener 1993 ; Li et al. 1995 ; Germann and Zawadzki 2002 ; Mandapaka et al. 2012 ; Hwang et al. 2015 ; Shi et al. 2015 ; Zou et al. 2019 ). To accurately nowcast precipitation at a local station using NWP

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Evan Ruzanski and V. Chandrasekar

K dp -based rainfall estimates produced using this method compared favorably to rain gauge measurements, using three seasons of data. This paper investigates the characteristics of nowcasting rainfall fields derived from K dp estimated using the method presented by Wang and Chandrasekar (2009) . These characteristics are compared with those using rainfall fields estimated from Z h by radar- and rain gauge–based validation. This paper is organized as follows: The nowcasting and assessment

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Kanghui Zhou, Yongguang Zheng, Wansheng Dong, and Tingbo Wang

of a growing thunderstorm ( Vincent et al. 2003 ). Radar reflectivity data can be used to indirectly identify the electrification process within a developing thunderstorm because graupel and hail particles return large reflectivity echoes ( Buechler and Goodman 1990 ; Vincent et al. 2003 ; Mosier et al. 2011 ). Hence, large reflectivity has been widely used as an indicator of the onset of cloud-to-ground (CG) lightning in studies of nowcasting (e.g., Mecikalski et al. 2013 ). The appearance of

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Sabino Metta, Jost von Hardenberg, Luca Ferraris, Nicola Rebora, and Antonello Provenzale

1. Introduction Short-range forecasting (nowcasting) of intense precipitation events has many applications in hydrometeorological risk management, including flash-flood warning and surface or air traffic control. Extensive weather radar networks are now operational in several countries, providing detailed snapshots of local precipitation conditions at high spatial and temporal resolution. The availability of these data allows for the development of nowcasting techniques that use radar fields as

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Paul J. Roebber and John Crockett

data are used to evaluate performance; all temperature results reported in this paper are based on the test data and are directly comparable to the results in Roebber (2018) . b. Convection occurrence nowcasts The AutoNowCaster (ANC; Mueller et al. 2003 ; Lakshmanan et al. 2012 ) generates 60-min nowcasts of convective likelihood (CL). As described in BXCS, these data span the period 11 June 2012–30 September 2012 (from 1400 to 2359 UTC each day) and lie on a 0.02° × 0.02° latitude

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