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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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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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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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Kevin Birk, Eric Lenning, Kevin Donofrio, and Matthew T. Friedlein

use of implicit techniques based on vertical thermal profiles rather than explicit techniques utilizing model microphysics. Reeves et al. (2016) discusses a number of limitations related to model microphysics schemes. One not mentioned is that when a model is struggling to match surface and upper-air observational trends, explicit precipitation-type output based on its microphysics will misrepresent what is actually occurring at a particular time and location. Tools for making real-time forecast

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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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Gui-Ying Yang, Samantha Ferrett, Steve Woolnough, John Methven, and Chris Holloway

current analyses and forecasts. The methodology is used to identify horizontal winds, geopotential height and hence divergence and vorticity structures associated with distinct equatorial wave types. This paper is organized as follows. Section 2 details the data used, briefly introduces the equatorial wave theory that is the basis for the diagnostic technique, and describes the spatial projection methodology used to identify equatorial waves. Section 3 presents the new time-window technique

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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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