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Christophe Accadia, Stefano Mariani, Marco Casaioli, Alfredo Lavagnini, and Antonio Speranza

QBOLAM 24-h accumulated precipitation forecasts were compared with equivalent forecasts produced by the European Centre for Medium-Range Weather Forecasts (ECMWF). Since these compared models have significantly different grid-box sizes, it was necessary to verify precipitation forecasts on a common grid. QBOLAM and LAMBO precipitation forecasts were remapped onto a regular 0.5°-spaced ECMWF grid using a remapping technique that conserves, to a desired degree of accuracy, the total forecast

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Nina Schuhen, Thordis L. Thorarinsdottir, and Tilmann Gneiting

1998 ; Grimit and Mass 2002 ), ensemble forecasts tend to be biased, and typically they are underdispersed ( Hamill and Colucci 1997 ), in that the ensemble spread is too small to be realistic. Furthermore, differing spatial resolutions of the forecast grid and the observation network may need to be reconciled. To address these shortcomings, various techniques for the statistical postprocessing of ensemble model output have been developed ( Wilks and Hamill 2007 ), including ensemble model output

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Chih-Chiang Wei

economic losses and casualties ( Hsu and Wei 2007 ). Therefore, a useful scheme for quantitative precipitation forecast (QPF) during typhoon periods is highly desired ( Chang et al. 1993 ; Lee et al. 2006 ; Wei and Hsu 2008a ). In Taiwan, Wang et al. (1986) first developed a technique using the climatology average method (a simple statistical approach developed from the spatial distribution of typhoon center) to forecast typhoon rainfalls over land in Taiwan. This method was adopted to be one of

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Jing Huang, Jun Du, and Weihong Qian

). Much of the increase in forecast skill can be attributed to improvements in model physics, increases in model resolution, and the availability of aircraft and satellite observations (e.g., Aberson 2010 ), as well as new data assimilation techniques (e.g., Hamill et al. 2011 ). For the infamous Atlantic-based Hurricane Sandy (2012), the European Centre for Medium-Range Weather Forecasts (ECMWF) global model accurately predicted its landfall location one week ahead of time ( Bassill 2014

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David G. Baggaley and John M. Hanesiak

. This present paper attempts to put more emphasis on the false alarm aspect by defining a credibility factor. This study is aimed at creating a practical technique for the prediction of significant blowing snow and the associated visibility reductions through available observational data. From an operational forecasting perspective, the definition of “significant” blowing snow varies with the application. For instance, a public weather forecast is mainly concerned with visibility less than 1 km

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Craig H. Bishop and Kevin T. Shanley

observations fall outside the range of values predicted by the raw ensemble with a frequency much greater than that expected if the ensemble forecasts were drawn from the distribution of truth given the forecast. Dressing ( Roulston and Smith 2002 ; Wang and Bishop 2005 ; Fortin et al. 2006 ) or Bayesian model averaging (BMA) techniques ( Raftery et al. 2005 ) are specifically designed to address the common problem of ensemble under dispersion and have been employed by, among others, Wilson et al. (2007

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Andrew N. Staniforth and Herschel L. Mitchell

APmL1978 ANDREW N. STANIFORTH AND HERSCHEL L. MITCHELL 439- A Variable-Resolution l*inite-Element Technique for Regional Forecasting with the Primitive Equations ANDREW N. STANiFORTH AND HERSCHEL L. MITCHELLIRecherche en Pr~vision Num~rique, Atmospheric Environment Service, Dorval, Quebec HPP 1J3 Canada (Manuscript received 27 June 1977, in final form 5 December 1977)ABSTRACT A

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Edward C. Johnston

JUNE 1995 KAPELA ET AL. 229 Forecasting the Impacts of Strong Wintertime Post-Cold Front Winds in the Northern Plains ANTON F. KAPELA National Weather Service Forecast Office, Sullivan, Wisconsin PRESTON W. LEFTWlCH National Weather Service, Central Region Scientific Services Division, Kansas City, Missouri

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Munehiko Yamaguchi and Naohisa Koide

–dynamical. One of the examples of the statistical approach is TC genesis guidance using the Dvorak technique ( Dvorak 1975 , 1984 ). Cossuth et al. (2013) statistically calculated the likelihood that tropical disturbances analyzed using the Dvorak technique at the National Hurricane Center (NHC) and the Central Pacific Hurricane Center from 2001 to 2011 reached TC intensity. The results can be used as a baseline or climatology for disturbance-based TC genesis forecasts. For the feasibility of NWP models

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Pradeep V. Mandapaka, Urs Germann, Luca Panziera, and Alessandro Hering

with high resolution, many radar-based very short-term QPF (also referred to as nowcasting) techniques were developed over the years (e.g., Austin and Bellon 1974 ; Seo and Smith 1992 ; Andrieu et al. 1996 ; Dolciné et al. 1997 ; Mecklenburg et al. 2000 ; Pierce et al. 2000 ; Germann and Zawadzki 2002 ; Mueller et al. 2003 ; Seed 2003 ; Bowler et al. 2004 , 2006 ). The radar echo extrapolation is one of the earlier and most widely used very short-term QPF techniques. The forecasts from

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