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Sen Chiao and Gregory S. Jenkins

western African coastline. 5. Discussion and conclusions The forecasting of developing tropical cyclones over the extreme eastern Atlantic remains challenging because of limited observations, the Guinea Highlands, and the interaction between mesoscale convective systems and larger-scale AEWs (2500–3000-km wavelength). Here, we have demonstrated the simulation of the disturbance associated with TD 4 (i.e., TS Debby) using 25- and 5-km grid spacings in the WRF model. This simulation, although not

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Juanzhen Sun, Mingxuan Chen, and Yingchun Wang

1. Introduction In preparation for the 2008 Summer Olympics in Beijing, China, the Beijing Meteorological Bureau (BMB) of China upgraded its mesoscale-observing network in the vicinity of Beijing. The upgraded network includes four Doppler radars, five radiosondes producing soundings at 6-h intervals during the Olympics, about 150 automated weather stations, three profilers, and about 40 GPS–Met receivers. The Beijing 2008 Forecast Demonstration Project (B08FDP; information online at www.bo8

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Israel L. Jirak and William R. Cotton

into a large, long-lived organized convective system ( Cotton and Anthes 1989 ). Thus, forecasting MCSs requires knowledge of areas favorable for convective initiation, organization, and sustenance over a range of spatial and time scales. Even though pinpointing the location of convective initiation is unlikely in most cases, considerable information pertinent to forecasting can still be learned about environments that are conducive for convective organization and sustenance. In fact, mesoscale

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Diego A. Alfaro and Michael C. Coniglio

Previous analyses indicate that CAPE ll could be useful in forecasting applications. The difficulty lies in CAPE ll not being a purely environmental index, as its value depends on the MCS’s MV, which is partly governed by mesoscale processes associated with the storm’s manifestation. To overcome this shortcoming, we diagnose MV using Corfidi vectors in forward-propagating MCSs ( Corfidi 2003 ), leading to a Corfidi layer-lifting CAPE (CAPE ll_Corfidi ). Corfidi vectors consider the movement of MCSs

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Weiguo Wang, Jason A. Sippel, Sergio Abarca, Lin Zhu, Bin Liu, Zhan Zhang, Avichal Mehra, and Vijay Tallapragada

, Kepert (2012) discussed the advantages and disadvantages of a variety of PBL schemes for TC simulations and concluded that caution needs to be taken when results are interpreted and that there might be need for tuning to compare with observations. The PBL scheme in the NCEP operational Hurricane Weather Research and Forecast (HWRF) Model has its roots in the PBL scheme of the NCEP Global Forecast System (GFS). The scheme uses a parametric profile of eddy diffusivity K matching the value in the

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Ching-Yuang Huang, Cher-Wei Chou, Shu-Hua Chen, and Jia-Hong Xie

). Topographical effects of a mesoscale mountain not only cause track deviations of approaching tropical cyclones but also enhance the rainfall over the mountain and thus greatly modify the rainfall distributions associated with the cyclones (e.g., Wu and Kuo 1999 ; Wu 2013 ). Wu and Kuo (1999) summarized the general characteristics of the typhoons impinging on Taiwan where the Central Mountain Range (CMR) peaks at 3.5 km and stretches about 300 km long and 100 km wide. One significant result of the

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Ching-Yuang Huang, Cher-Wei Chou, Shu-Hua Chen, and Jia-Hong Xie

). Topographical effects of a mesoscale mountain not only cause track deviations of approaching tropical cyclones but also enhance the rainfall over the mountain and thus greatly modify the rainfall distributions associated with the cyclones (e.g., Wu and Kuo 1999 ; Wu 2013 ). Wu and Kuo (1999) summarized the general characteristics of the typhoons impinging on Taiwan where the Central Mountain Range (CMR) peaks at 3.5 km and stretches about 300 km long and 100 km wide. One significant result of the

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Christopher J. Schultz, Walter A. Petersen, and Lawrence D. Carey

convective storms had little if any CG lightning associated with them. With the more recent advent of VHF total lightning mapping arrays that continuously detect and locate leader sources in the total lightning flash component (IC + CG) over mesoscale regional domains ( Williams et al. 1999 ; Lang et al. 2004 ; Koshak et al. 2004 ; MacGorman et al. 2008 ; Krehbiel 2008 ), it has now become much easier to evaluate and quantify how well related manifestations of thunderstorm electrical activity such as

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Brian J. Squitieri and William A. Gallus Jr.

://doi.org/10.5065/D6RX99HX . 10.5065/D6RX99HX Coniglio , M. C. , J. Y. Hwang , and D. J. Stensrud , 2010 : Environmental factors in the upscale growth and longevity of MCSs derived from Rapid Update Cycle analyses . Mon. Wea. Rev. , 138 , 3514 – 3539 , https://doi.org/10.1175/2010MWR3233.1 . 10.1175/2010MWR3233.1 Davis , C. A. , B. G. Brown , and R. G. Bullock , 2006a : Object-based verification of precipitation forecasts. Part I: Methods and application to mesoscale rain areas . Mon

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Sheng-Lun Tai, Yu-Chieng Liou, Juanzhen Sun, Shao-Fan Chang, and Min-Chao Kuo

focusing on the quantitative precipitation forecast (QPF). It is known that the 4DVAR method requires an adjoint model, whose numerical scheme structures need to closely follow the prognostic model used for performing forward time integration. Greater complexity in the model development is expected if the terrain is to be resolved. The Japan Meteorological Agency (JMA) has established operational mesoscale models equipped with 4DVAR data assimilation capability ( Saito et al. 2006 ). These systems use

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