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Tongtiegang Zhao, James C. Bennett, Q. J. Wang, Andrew Schepen, Andrew W. Wood, David E. Robertson, and Maria-Helena Ramos

1. Introduction Ensemble forecasts of seasonal precipitation from coupled ocean–atmosphere general circulation models (GCMs) have mostly replaced traditional statistical forecasts as the basis of operational outlooks issued by many national weather services. For example, the National Centers for Environmental Prediction (NCEP) in the United States has operated its Climate Forecast System (CFS) since 2004 ( Saha et al. 2014 ), the European Centre for Medium-Range Weather Forecasts (ECMWF) has

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Joseph R. Bocchieri and George J. Maglaras

VOL. Ill, NO. 3 MONTHLY WEATHER REVIEW MARCH 1983An Improved Operational System for Forecasting Precipitation Type JOSEPH R. BOCCHIERII AND GEORGE J. MAGLARASTechniques Development Laboratory, National Weather Service, NOAA, Silver Spring, MD 20910(Manuscript received I May 1982, in final form 7 December 1982) ABSTRACT A Model Output Statistics system for forecasting the

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Charles R. Sampson, James A. Hansen, Paul A. Wittmann, John A. Knaff, and Andrea Schumacher

input to WAVEWATCH III (e.g., Tolman et al. 2005 ), which can result in more realistic wave fields in the vicinity of the TC (e.g., Chao and Tolman 2010 ). One disadvantage to using exclusively NWP model winds is that they are inconsistent with the official forecasts from the operational centers (e.g., JTWC). To alleviate this shortcoming, Sampson et al. (2010) implemented an algorithm to use the official forecast (track, intensity, and wind structure) placed within a global NWP model’s output

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James P. Kossin and Matthew Sitkowski

1. Introduction Typically, the formation of a secondary (outer) concentric eyewall in a hurricane signals an impending fluctuation in the storm’s ongoing intensity evolution ( Fig. 1 ). These fluctuations are anomalous in that they constitute a transient behavior that is generally not captured well by the present suite of operational intensity forecast guidance. Consequently, when the formation of a secondary eyewall is observed (or predicted; e.g., Kossin and Sitkowski 2009 ) in an

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I. Gultepe, M. D. Müller, and Z. Boybeyi

idealized two-dimensional mountain to investigate various aspects of a bulk, mixed-phase microphysical parameterization found in the fifth-generation Pennsylvania State University–National Center for Atmospheric Research Mesoscale Model (MM5), the RUC model, and the Weather Research and Forecast model. They stated that bin models are computationally very expensive and that, for this reason, bin models are not yet viable for real-time operational NWP runs. In their application, N d was assumed to be 50

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Jonathan D. W. Kahl

projections. It should be noted, however, that unlike climatology forecasts, persistence forecasts of peak gusts may not be operationally feasible because they require the archival of gust observations free of the restrictive reporting protocols accompanying the hourly ASOS dataset ( HK17 ). Fig . 5. Mean absolute errors in peak gust forecasts at KPVD. (a) PERS model, (b) GFNAM model, and (c) GFGFS model. Climatology (CLIM) and perfect prog (PPROG) forecast errors are included in all panels. Models and

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Weiwei Li, Zhuo Wang, Melinda S. Peng, and James A. Ridout

presented in an attempt to gain insight into the deficiencies of the model physics on the intraseasonal time scales. The forecast system chosen for evaluation in this study is the Navy Operational Global Atmospheric Prediction System (NOGAPS). NOGAPS, developed at the Naval Research Laboratory (NRL), had been running operationally at the U.S. Navy’s Fleet Numerical Meteorology and Oceanography Center (FNMOC) since 1982, and was replaced with the Navy Global Environmental Model (NAVGEM) in March 2013

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Richard L. Wobus and Eugenia Kalnay

2132 MONTHLY WEATHER REVIEW VOLUME 123Three Years of Operational Prediction of Forecast Skill at NMC PaCHARD L. WOBUS * AND EUGENIA KALNAYDevelopment Division, National Meteorological Center, Washington, D.C.(Manuscript received 28 January 1994, in final form 3 $anuary 1995)ABSTRACT In real time since 1990, the National Meteorological Center (NMC) has been running a system to

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Renaud Marty, Isabella Zin, Charles Obled, Guillaume Bontron, and Abdelatif Djerboua

1. Introduction Catchments of southern France are regularly subject to flash floods generated by intense-rainfall events—generally in the autumn (i.e., from September to December). Thus, flood forecasting requires an appropriate anticipation of future rainfall: to issue an early flood warning, at least 12–24 h before the event; to alert operational or safety services, at least 2–3 days ahead. Such quantitative precipitation forecasts (QPF) are generally provided by numerical weather prediction

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Jianping Huang, Jeffery McQueen, James Wilczak, Irina Djalalova, Ivanka Stajner, Perry Shafran, Dave Allured, Pius Lee, Li Pan, Daniel Tong, Ho-Chun Huang, Geoffrey DiMego, Sikchya Upadhayay, and Luca Delle Monache

important to provide numerical forecast guidance as a basis for alerting the public to avoid or reduce exposure to unhealthy levels of PM 2.5 . The goal of the National Oceanic and Atmospheric Administration (NOAA) National Air Quality Forecasting Capability (NAQFC) is to provide timely and accurate operational numerical guidance for surface O 3 and PM 2.5 concentrations. The NAQFC was established by NOAA in partnership with the EPA to provide ozone and particulate matter pollutant forecasts. The

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