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David R. Novak, David R. Bright, and Michael J. Brennan

1. Introduction Uncertainty is a fundamental characteristic of hydrometeorological (hydrologic, weather, and seasonal climate) prediction, and is a consequence of the inherent chaotic nature of the atmosphere, inadequate observations, and numerical weather prediction (NWP) deficiencies ( NRC 2006 ). Thus, the assessment and communication of uncertainty is an inherent part of any forecast process. The assessment of uncertainty in modern operational forecasting has largely relied on the use of

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Chermelle Engel and Elizabeth Ebert

techniques that try to predict the best “model of the day” ( Hibon and Evgeniou 2005 ; Fritsch et al. 2000 ). Combining multiple individual forecasts to increase accuracy is an approach used in various fields from business to psychology ( Clemen 1989 ). The operational consensus forecast (OCF) scheme developed at the Bureau combines multimodel guidance. Daily OCF has been shown to produce objective guidance for forecast fields such as maximum and minimum daily air temperatures that is competitive with

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Ralph F. Milliff and Peter A. Stamus

1. Introduction The research value of satellite ocean surface vector wind (SVW) data has been well established over more than a decade of published work, across a broad range of studies. What is also emerging is that these data play essential roles in many operational applications as well, including (i) numerical weather prediction (NWP) and (ii) the manual production of forecasts, analyses, and warnings by trained analysts (i.e., forecasters). SVW impacts in NWP have been highlighted recently

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Jose-Henrique G. M. Alves, Arun Chawla, Hendrik L. Tolman, David Schwab, Gregory Lang, and Greg Mann

. The current paper describes the challenges faced, and solutions adopted by the wave modeling group at the Environmental Modeling Center of NOAA’s National Centers for Environmental Prediction (NCEP), which led to the successful deployment of a Great Lakes wave forecasting system using the third-generation model WAVEWATCH III ( Tolman 2002b ; Tolman et al. 2002 ). Performance of the current operational wave forecasting system for the Great Lakes, and the impacts of scheduled upgrades that will

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Namyoung Kang

as the probability that a storm will fall somewhere within a particular distance close enough to a location (i.e., 140 km) ( Jarrell and Brand 1983 ). This is why the potential area of the storm wind occurrence is more useful information than track uncertainty itself since a track is only the center of danger. Successful representation of the forecast uncertainty has been available in operations, using Monte Carlo sampling from past operational forecasts ( DeMaria et al. 2009 ). Owing to the

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Keqi Zhang, Yuepeng Li, Huiqing Liu, Jamie Rhome, and Cristina Forbes

continuity equation by maintaining nonlinear advective acceleration and diffusion terms. These models and their extensions also include the wetting–drying component and have recently been applied to the simulation of overland flooding ( Bunya et al. 2010 ; Forbes et al. 2009 ; Forbes et al. 2010 ; Huang et al. 2010 ; Shen et al. 2006 ; Sheng et al. 2010 ; Xie et al. 2004 ; Xu et al. 2010 ). However, these models cannot be used directly for operational surge forecasts because most of them are

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Natacha B. Bernier, Jose-Henrique G. M. Alves, Hendrik Tolman, Arun Chawla, Syd Peel, Benoit Pouliot, Jean-Marc Bélanger, Pierre Pellerin, Mario Lépine, and Michel Roch

continues to receive considerable attention from both the research and operational communities (e.g., Tolman et al. 2013 ). Several countries have already developed and implemented global wave forecast systems—for example, the European Center for Medium-Range Weather Forecasts [ Bidlot (2012) and references therein], the Met Office ( Li and Saulter 2014 ), the U.S. Navy ( Rogers et al. 2014 ), and the National Centers for Environmental Prediction ( Chawla et al. 2013 ), and additional centers are

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Xu Zhang, Yuhua Yang, Baode Chen, and Wei Huang

1. Introduction As computational power has increased, limited-area operational numerical weather prediction (NWP) models with horizontal grid spacing of 1–10 km for short-range weather forecasting are introduced in many operational forecast centers. At such scales, many models have typically been configured without using a convection parameterization scheme (CPS). However, such a configuration generally leads to subgrid convective updrafts being forced on the grid scale and precipitation with

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Arun Chawla, Hendrik L. Tolman, Vera Gerald, Deanna Spindler, Todd Spindler, Jose-Henrique G. M. Alves, Degui Cao, Jeffrey L. Hanson, and Eve-Marie Devaliere

1. Introduction At operational centers like the National Centers for Environmental Prediction (NCEP), numerical models are used to obtain initial forecast guidance that are then used by forecasters who, after accounting for known model errors, issue official forecasts. From a forecaster's point of view, a valuable model guidance system needs to be (a) as close as possible to the ground truth and (b) delivered in a timely fashion so that it can be used to develop a forecast. Thus, considerable

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Joshua H. Cossuth, Richard D. Knabb, Daniel P. Brown, and Robert E. Hart

). Tropical cyclogenesis has therefore become the subject of extensive research. Further, the operational community has begun to enhance their public products, including forecasts of TC formation, due to great user interest in that information. This paper describes historical data and analyses and their use in producing a forecasting tool that can assist operational centers in making present-day genesis forecasts and in assessing the skill of new and future forecast capabilities arising from ongoing

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