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Benjamin Root, Paul Knight, George Young, Steven Greybush, Richard Grumm, Ron Holmes, and Jeremy Ross

over a limited domain. The key difference in the current work is that the analog technique is applied to NWP forecast maps as a pattern-recognition tool rather than to analysis maps as a forecast tool. Thus, the forecast skill of the system depends in large measure on the underlying NWP model rather than on the subsequent application of analogs. In this paper, a method is presented that leverages the existence of limited-area analogs ( Van den Dool 1994 ) and distinct weather patterns or

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Sarah A. Baker, Andrew W. Wood, and Balaji Rajagopalan

climatological correction without considering forecast skill. The authors demonstrate that forecast calibration techniques (e.g., the Bayesian joint probability method) are needed to account for skill in the course of adjusting both forecast mean and forecast spread. Some statistical postprocessing techniques employ additional information from large-scale climate fields to improve dynamical model forecasts. Many studies have focused on improving seasonal precipitation and temperature forecasts ( DelSole and

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K. Fraedrich and L. M. Leslie

AUOUST 1987 K. FRAEDRICH AND L. M. LESLIE 1645Evaluation of Techniques for the Operational, Single Station, Short-Term Forecasting of Rainfall at a Midlatitude Station (Melbourne) K. FRAEDRICH* AND L. M. LESLIEBureau of Meteorology Research Centre, Melbourne, Victoria, 3001, Australia(Manuscript received 22 September 1986, in final form 21 January 1987)ABSTRACT Probabilit~ of

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Adam Winstral, Tobias Jonas, and Nora Helbig

probability density functions at 31 stations in the north-central United States from National Centers for Environmental Prediction–National Center for Atmospheric Research (NCEP–NCAR) reanalyses data (~200 km resolution), while Curry et al. (2012) sought statistical relationships between climate forecast variables and similar reanalysis data to derive monthly Weibull distribution parameters. Huang et al. (2015) used a combination of physical and statistical nondynamic downscaling techniques to test if

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Samantha L. Lynch and Russ S. Schumacher

) and Mullen and Buizza (2001) also found that the accuracy in precipitation forecasts decreases as the rainfall threshold increases. Hakim and Torn (2008) introduced the technique of ensemble synoptic analysis for an extratropical cyclone, finding the relationships between different synoptic features by computing statistical operators such as covariances and correlations within an ensemble of forecasts. Similarly, Torn (2010) used this method to examine the dynamical mechanisms that led to

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Manuel Gebetsberger, Jakob W. Messner, Georg J. Mayr, and Achim Zeileis

, and G. Brunet , 2015 : The quiet revolution of numerical weather prediction . Nature , 525 , 47 – 55 , doi: 10.1038/nature14956 . 10.1038/nature14956 Ben Bouallègue , Z. , and S. E. Theis , 2014 : Spatial techniques applied to precipitation ensemble forecasts: From verification results to probabilistic products . Meteor. Appl. , 21 , 922 – 929 , doi: 10.1002/met.1435 . 10.1002/met.1435 Bentzien , S. , and P. Friederichs , 2012 : Generating and calibrating probabilistic

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Weihong Qian, Ning Jiang, and Jun Du

,” “no meteorological evidence is presented for why areas of moist vorticity and moist divergence should overlap with regions of 24-h accumulated rainfall,” and “all three quantities have not been verified against the output of precipitation directly from the model nor is the approach of combining meteorological quantities into a single parameter appropriate in an ingredients-based forecasting approach.” The first two points concern scientific justification mathematically and meteorologically, while

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J. Brotzge and S. Erickson

associated NWS warning; a list of those tornadoes without advance NWS warning was also provided. These reports contained the date and location of each tornado, the time of the event, the time the NWS warning was issued, the weather forecast office (WFO) that issued the warning, the county or parish location, the estimated F-scale rating, the number of fatalities and estimates of the damage. Additional information on each zero and negative lead-time event was obtained from the National Climatic Data

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Xingqin Fang and Ying-Hwa Kuo

produce excessive rainfall at the southern tip of the CMR (see Fang et al. 2011 ). Although the exact reason for this rainfall overprediction bias is still not clear, such a topographically locked rainfall bias will be amplified by the probability-matching technique. In this paper, we develop a modified probability-matching technique for ensemble forecasting of the topography-enhanced typhoon heavy rainfall over Taiwan. The basic idea is to collect the track and rainfall forecasts from a large

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Yong Wang, Martin Bellus, Jean-Francois Geleyn, Xulin Ma, Weihong Tian, and Florian Weidle

1. Introduction Ensemble prediction techniques have been applied in most numerical weather prediction (NWP) centers as a dynamical way of accounting for the forecast uncertainty. The optimal design of an ensemble prediction system (EPS) strongly depends on the quantification of uncertainties due to errors in initial conditions (ICs), model formulation, and physical parameterizations. Additional challenges posed for a skillful regional EPS include, for example, the problem of quantifying the

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