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Joby L. Hilliker, Girish Akasapu, and George S. Young

1. Introduction Improved short-term weather forecasting has been an increased focus in meteorology, in part because of the myriad of applications for accurate short-term (1–12 h, as defined here) forecasts at the economic level. As examples from the transportation industry, short-term forecasts of thunderstorms and low ceiling are beneficial to aviation ( Fabbian et al. 2007 ; Hilliker et al. 2007 ; Ghirardelli and Glahn 2010 ), while developed forecasting techniques of other weather

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David N. Yates, Thomas T. Warner, and George H. Leavesley

Introduction The companion to this paper ( Warner et al. 2000 ) describes radar estimates and two types of forecasts of rainfall associated with a thunderstorm that produced a flash flood in the Buffalo Creek watershed located in the mountainous Front Range near Denver, Colorado, on 12 July 1996. This paper describes the use of those precipitation estimates as input to a distributed-parameter hydrologic model that was used to simulate the flash flood itself. This event is an especially

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Aitor Atencia, Isztar Zawadzki, and Marc Berenguer

1. Introduction Lagrangian extrapolation of the latest radar precipitation (e.g., Germann and Zawadzki 2002 ; Seed 2003 ; Berenguer et al. 2005 ) has shown skill in forecasting the precipitation field with high resolution for lead times up to 6 h (known as nowcasting) or even for longer lead times up to 12 h [known as very short-range forecasting (VSRF)]. This technique estimates the motion of the precipitation field with a tracking algorithm and generates the forecasts by using the

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Jean Philippe Piedelievre, Lue Musson-Genon, and François Bompay

forecasting model, which makes the computingtime of this model very low. Turbulent diffusion is modeled using exchange coefficients, Louis' formulation forvertical diffusion and constant parameters for horizontal diffusion. A scavenging ratio is used for wet deposition,and dry deposition is parameterized in terms of deposition velocity. The operational objective of our work hasled us to use well-documented numerical techniques (a Crank-Nicholson scheme combined with a splittingtechnique). Results obtained

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Jared A. Lee, Sue Ellen Haupt, Pedro A. Jiménez, Matthew A. Rogers, Steven D. Miller, and Tyler C. McCandless

et al. 2016 ). There are various techniques available to make nowcasts (short-range intraday forecasts on time scales of 0–6 h) of GHI. The first, and simplest, technique is a “smart persistence” forecast. Smart persistence forecasts begin with the most recent observations of GHI (or clearness index, which is the ratio of ground-level GHI to top-of-atmosphere GHI) and integrate them forward in time, accounting for changing solar zenith angle and the associated transmission adjustment

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Anna E. Jones, Tanya Bowden, and John Turner

) and 2%–3.5% (Southern Hemisphere) depending on time of year. Note, however, that when developing this method, analyzed temperature data only were used, which will favor lower ozone forecast errors than if using forecast temperatures, and also a smoothed TOMS dataset were used (5° latitude by 15° longitude). In addition, they investigated the benefit of using a multivariable model and found that the ozone prediction errors were either comparable or larger when using this technique. In a similar

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Steven D. Miller, Thomas F. Lee, and Robert L. Fennimore

applications. However, next-generation geostationary satellites will have the necessary spectral resolution (and increased spatial resolution) to employ variants of the techniques described here. The improved ability to characterize the full extent of a snowfield via temporal cloud-clearing techniques promises to be a boon for applications of this kind. Conclusions Feedback from military users confirms the usefulness of these products in remote forecasting regions. In maintaining the original spatial

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Ronald M. Reap

forecasts generated by the six-layer primitive equation model of the National Meteorological Center. Detailed24-hr forecasts of temperature and dew point, designed for application to severe storm prediction, arederived by computing the 6-hr variations of potential temperature and mixing ratio for air parcels assumedto follow paths defined by the trajectories. Initial values at the trajectory origin points are provided byan objective analysis technique which reproduces detailed patterns and gradients

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Yaodeng Chen, Hongli Wang, Jinzhong Min, Xiang-Yu Huang, Patrick Minnis, Ruizhi Zhang, Julie Haggerty, and Rabindra Palikonda

observations than that from EXP-CON. Additionally, the precipitation intensity forecast near the rainfall center was improved as well. Fig . 11. Averaged 24-h accumulated precipitation: (a) Climate Prediction Center (CPC) morphing technique (CMORPH) precipitation analysis, (b) EXP-CWP, and (c) EXP-CON. To provide a quantitative measure of the precipitation forecast skill, the effect of assimilating CWP on precipitation forecasts was assessed using the threat score (TS). Figure 12 shows TS for different

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Merlin P. Lawson and Randall S. Cerveny

, particularly in the equatorial Pacific (e.g., Barnett, 1981a).Knowledge gained through this work is being developed and applied to modeling experiments, withmodest success (e.g., Chervin et al., 1980). Until fullunderstanding is achieved, in order to successfullyforecast beyond a few weeks, we will have to relymore on the estimation of synoptic tendencies withthe use of statistical aggregates. The forecasting techniques developed primarily for generating these estimates have traditionally involved the use

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