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C-H. Moeng, Jimy Dudhia, Joe Klemp, and Peter Sullivan

explicitly resolve both turbulent and mesoscale motions of interest through two-way nesting, which allows for the feedback of turbulence effects to mesoscale prediction. With increasing computer power, this multiscale two-way nesting approach is becoming feasible in the near future. However, questions as how specified nest boundaries affect turbulent simulation and how turbulent statistics respond to grid nesting have not been explored. In this study, we examine grid nesting for LES using the Weather

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Peter T. May

day of the experiment. Interactions between gust fronts and between gust fronts and sea-breeze fronts were crucial for the evolution of the storms (e.g., Carbone et al. 1997 ; Wilson et al. 1997 ). On two occasions, the wind profiler/Radio Acoustic Sounding System (RASS; May et al. 1990 ) at Maxwell Creek ( Fig. 1 ) was switched from a routine wind and RASS measuring cycle to a continuous RASS measurement mode as gust fronts detected using the C-Pol Doppler radar were approaching. High time

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as long as one hour before itarrived.Then he makes the following noteworthy remark:As thi? noise still occurs when a whirl is aloft (though to alesser extent), it is not due entirely to the destruction beingcaused by the wind, but is due also to vibrations createdby frictional effects in the strong wind shear of the whirl.Such Bounds are augmented by long rolls of thunder, whichmay overlap to make a nearly continuous background ofrumble.It thus appears, from the quotations cited above andfrom

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Nicholas T. Luchetti, Katja Friedrich, Christopher E. Rodell, and Julie K. Lundquist

. Hazen , D. Wolfe , R. Delgado , S. Oncley , and J. K. Lundquist , 2017 : Assessing the accuracy of microwave radiometers and radio acoustic sounding systems for wind energy applications . Atmos. Meas. Tech. , 10 , 1707 – 1721 , . 10.5194/amt-10-1707-2017 Bidokhti , A. A. , and T. Bani-Hashem , 2001 : Structure of thunderstorm gust fronts with topographic effects . Adv. Atmos. Sci. , 18 , 1161 – 1174 ,

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Thibaut Montmerle

summer 2009 instead. For each events, four forecast–assimilation steps have been performed prior to the last 3-h forecasts used to calibrate the statistics in order to better take into account errors from the boundaries. Binary geographical masks, deduced from a threshold applied on vertically integrated rain computed for each background perturbations, have then been applied to the differences between pairs of forecasts. To alleviate subsampling effects, an inflation deduced from the size of the mean

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F. M. Ralph, L. Armi, J. M. Bane, C. Dorman, W. D. Neff, P. J. Neiman, W. Nuss, and P. O. G. Persson

al. 1987 ). The disturbance is trapped along coastal mountains by Coriolis effects, propagates parallel to the mountains, and is expected to decay exponentially offshore, within approximately 100 km (i.e., the Rossby radius of deformation). Through other case studies it was recognized that the transitions to southerly flow sometimes more closely resembled a density current ( Mass and Albright 1987 ; Dorman 1987 ; Hermann et al. 1990 )—that is, the transitions were more abrupt, were associated

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David C. Bader and Thomas B. McKee

1991) ABSTRACT The development of the nocturnal boundary layer (NBL) over a sloping plateau upwind of a high mountainbarrier is studied with a numerical model and field observations. Six numerical simulations and one observedease are used to describe the effects of wind speed, wind direction, and sunset mixed-layer depth on the NBLstructure 6 h after sunset. When there is a component of wind into barrier, a two.layer structure develops. A75-175-m-deep inversion layer that is

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Liying Qian, George S. Young, and William M. Frank

convective updrafts. Most deep convection is organized on the mesoscale, with much of it occurring in mesoscale convective systems (MCSs) (e.g., Houze and Betts 1981 ; Chen et al. 1996 ). An individual MCS is typically too small to be resolved explicitly by a GCM, so the effects of both the MCS itself and the embedded convection must be parameterized. A widely accepted schematic of a typical MCS (in this case a tropical cloud line system) is shown in Fig. 1 ( Zipser 1977 ). Regardless of the

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Shu-Hsien Chou and David Atlas

sensitive todivergence, but are affected by the initial lapse rate of potential temperature; the greater the stability, thesmaller the heating, other factors being equal. Unless one knows the lapse rate at the shore, this requiresanother independent measurement. For this purpose, we propose to use the downwind slope of the squareof the boundary layer height, the mean value of which is also directly proportional to the mean sensibleheating. The height of the boundary layer should be measurable by future

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Paul J. Neiman, F. Martin Ralph, Robert L. Weber, Taneil Uttal, Louisa B. Nance, and David H. Levinson

Cyclones: The Erik Palmén Memorial Volume, C. W. Newton and E. Holopainen, Eds., Amer. Meteor. Soc., 107–127 . Wakimoto , R. M. , 1982 : The life cycle of thunderstorm gust fronts as viewed with Doppler radar and rawinsonde data. Mon. Wea. Rev , 110 , 1060 – 1082 . Weber , B. L. , D. B. Wuertz , D. C. Law , A. S. Frisch , and J. M. Brown , 1992 : Effects of small-scale vertical motion on radar measurements of wind and temperature profiles. J. Atmos. Oceanic Technol , 9 , 193

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