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Hamish A. Ramsay, Lance M. Leslie, and Jeffrey D. Kepert

resolution in the boundary layer and upper troposphere to more accurately resolve the inflow and outflow layers of the TC. The model top was set at 50 hPa. The simulation was initialized at 1200 UTC 17 March and run for 72 h until the TC decayed roughly to the Australian category 1 strength (i.e., gusts to 35 m s −1 ) about 12 h after landfall. The initial and lateral boundary conditions were provided by the National Centers for Environmental Prediction (NCEP) Final Analysis (FNL) dataset that has 1° × 1

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Jianhua Sun and Sixiong Zhao

understand the synoptic background and weather conditions for freezing precipitation events. The previous studies have mainly focused on various regions in North America and Europe, while only very limited number of studies were conducted in China. The investigations in the past with respect to the prediction of freezing precipitation or precipitation types generally fall into the following three categories: (a) Statistical models [e.g., critical thresholds, regression analysis, model output

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Howard B. Bluestein

/National Weather Service (NWS) moves from a policy of “warn on detection” to one of “warn on forecast” (information online at ). While the synoptic conditions for strong supercells were evident over a relatively broad area, the location(s) of the storm formation and the nature of the subsequent storm evolution were not well anticipated. The initial supercell formed within a region of cirrus overcast, which had some breaks. The presence of cirrus overcast

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Huijun Wang and Ke Fan

tier” approaches have been applied from the very beginning of dynamical seasonal climate prediction. In these models, the predictions are made by the atmospheric general circulation model (AGCM) forced with prescribed (or forecasted) sea surface temperatures (SST) and other boundary conditions. Multimodel superensemble predictions have been used in climate prediction to produce more reliable probability forecasts in recent years ( Krishnamurti et al. 1999 ; Palmer 2001 ). Two well-known projects

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M. Issa Lélé and Peter J. Lamb

Sahara Desert. At the surface, the wind direction discontinuity is characterized by pronounced temperature and humidity gradients that migrate seasonally northward then southward, lagging somewhat the zenith angle of the sun in the northern tropics. Between the surface and about 700 hPa, the ITF slopes upward to the south at inclinations between 1:100 and 1:400 ( Hastenrath and Lamb 1977 ; Hastenrath 1991 , 166–174) and is the upper boundary of the meridionally migrating wedge of monsoon air. The

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Rong-Hua Zhang and Antonio J. Busalacchi

-induced surface wind responses to SST TIW forcing, partly because of low resolutions in the horizontal and vertical, and/or because of unrealistic parameterizations of relevant processes in the atmospheric PBL [another limitations are in the accuracy and resolution of the SST boundary conditions specified for dynamical atmospheric models ( Chelton 2005 )]. In this work, we adopt a statistical approach to modeling TIW-induced surface wind variability, specifically relating τ TIW response to SST TIW forcing

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