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WILLIAM LEWIS

depression are made for periods up t o 36 hours using observed700-mb. charts and initial and 12-hr. forecast vertical motion charts from the JNWP Unit's thermotropic model.Results show that moisture can be successfully forecast by this technique. Through establishment of a relationshipbetween 700-mb. dewpoint depression, instantaneous vertical velocity, and large-scale weather, a forecast scheme isdevised using forecast 700-mb. dewpoint depression and forecast vertical motion from the thermotropic model

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E. LEE GERALDSON

September 1968E. Lee Geraldson649A COMPARISON OF THE ACCURACY OF OBJECTIVE TECHNIQUES FOR FORECASTING TYPHOON MOVEMENT DURING 1967E. LEE GERALDSONJoint Typhoon Warning Center, GuamABSTRACTIn the past, many objective techniques have been evaluated for severe tropical cyclones in the Atlantic, butlittle has been done along this line in the Pacific. A computer program was developed at the Joint Typhoon WarningCenter, to verify 10 separate 24-hr. forecast techniques. During the course of the 1967

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Luying Ji, Xiefei Zhi, Clemens Simmer, Shoupeng Zhu, and Yan Ji

et al. (2006) is adopted for calculating verification scores in this study. MODE is a typical feature-based displacement approach and an example for a spatial diagnostic technique. MODE attempts to mimic the way a human would subjectively evaluate a forecast via setting a precipitation threshold and spatially convoluting (scale-dependent averaging) the precipitation field. The median of maximum interest (MMI; Davis et al. 2009 ) and the object-based threat score (OTS; Johnson et al. 2011a

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Andrew J. Condon, Y. Peter Sheng, and Vladimir A. Paramygin

which can be important. As pointed out by Rego and Li (2009) and Jelesnianski (1972) , neglecting the forward speed and angle of approach may not be appropriate as there is a “critical motion relative to a coast that gives the highest possible surge.” Additionally the technique does not account for tides and wave setup, which can contribute significantly to the surge and inundation. This paper addresses the rapid generation of high-resolution probabilistic inundation forecasts. The optimal storm

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Sim D. Aberson, Sharanya J. Majumdar, Carolyn A. Reynolds, and Brian J. Etherton

statistically significant GFS track forecast error reduction of up to 25%, thereby yielding larger improvements than were possible by assimilating all available surveillance data. The deficiencies of symmetric sampling were attributed to suboptimal data assimilation schemes and their impact near targets that were bisected or otherwise not fully sampled. Advanced techniques, such as the ensemble transform Kalman filter (ETKF; Bishop et al. 2001 ) and singular vectors (SVs; Palmer et al. 1998 ), have

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Fan Han and Istvan Szunyogh

1. Introduction In a pair of papers, Keil and Craig (2007 , 2009 ; hereafter KC07 and KC09 , respectively) introduced a morphing-based, nonparametric optical flow technique ( Marzban et al. 2009 ) for the verification of precipitation forecasts. Their technique was most recently used by Geiß (2015) to examine the forecast cases of the Mesoscale Verification Intercomparison over Complex Terrain (MesoVICT) research project ( Dorninger et al. 2013 ). In an earlier paper ( Han and Szunyogh

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Bruce A. Veenhuis

and Loughe 1998 ). The ensemble members sample the various sources of error that degrade NWP forecasts. To quantify the error in the underlying analysis, the ensemble members are initialized with perturbed initial conditions. Over the years, a range of perturbation techniques have been proposed including the breeding method ( Toth and Kalnay 1997 ), singular vectors ( Palmer et al. 1998 ), and the ensemble transform Kalman filter ( Wang and Bishop 2003 ). The numerical model itself is also a

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Russell L. Elsberry, Edward L. Weniger, and Denis H. Meanor

2142 MONTHLY WEATHER REVIEW VOLUME I16A Statistical Tropical Cyclone Intensity Forecast Technique Incorporating Environmental Wind and Vertical Wind Shear InformationRUSSELL L. ELSBERRY, EDWARD L. WENIOER AND DENIS H. IVIEANORDepartment of Meteorology, Naval Postgraduate School, Monterey, CaliforniaManuscript received 8 Februar~ 1988, in final form 1 April 19gg) An objective technique for

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Carolyn A. Reynolds

1. Introduction Given the demonstrated importance of accurate initial conditions for forecast skill (e.g., Rabier et al. 1996 ), as well as the importance of accurate reanalyses for atmospheric process studies, there has been much interest in techniques designed to diagnose analysis errors. Techniques for identifying the fastest growing part of the analysis error include adjoint and singular vector–based methods ( Rabier et al. 1996 ; Buizza et al. 1997 ). Because these

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TAKASHI NITTA and JOHN B. HOVERMALE

652MONTHLY WEATHER REVIEW Vol. 97, No. 9UDC 551.509.313A TECHNIQUE OF OBJECTIVE ANALYSIS AND INITIALIZATION FOR THE PRIMITIVE FORECAST EQUATIONS TAKASHI NlTTA and JOHN B. HOVERMALE *National Meteorological Center, Weather Bureau, ESSA, Washington D.C.AB!7RACTA technique .of initialization for the primitive forecast equations is presented. The method consists of a march-ing prediction scheme performed in such a manner that the large-scale solution remains approximately steady

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