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Gerald M. Heymsfield, Lin Tian, Andrew J. Heymsfield, Lihua Li, and Stephen Guimond

strongest 10% of updrafts and downdrafts in hurricanes had averages of 4.2 and 2.6 m s −1 , respectively, and peak updrafts of ∼8 m s −1 . Anderson et al. (2005) examined updrafts in tropical convective storms using measurements from the higher-altitude Citation jet aircraft. They examined similarities between tropical oceanic and land cases from TRMM Large-Scale Biosphere–Atmosphere Experiment in Amazonia (LBA) and the Kwajalein Experiment (KWAJEX). Unlike earlier studies that used flight level data

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Chuntao Liu, Earle R. Williams, Edward J. Zipser, and Gary Burns

center locations over land) with 30-dB Z echo top temperature ( T 30dB Z ) below −10°C have lightning. About 10% of oceanic PFs (geographical center locations over ocean) with T 30dB Z below −17°C have lightning. These criteria are consistent with the analysis using three years of TRMM observations by Cecil et al. (2005) . Using 10% probability, we may arbitrarily define the electrified shower clouds (without lightning) by two steps. First, the temperature of the maximum height of 30 dB Z for

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Robert Cifelli, Timothy Lang, Steven A. Rutledge, Nick Guy, Edward J. Zipser, Jon Zawislak, and Robert Holzworth

suggests the importance of low-level drop growth and/or lack of evaporation at the ocean site compared to the land sites. The relatively uniform reflectivity profile at low levels observed in the land sites suggests more of a balance of growth and breakup processes. Similar observations were reported by Fuentes et al. (2008) using TRMM data. In the stratiform regions, the radar brightband signature is evident at both continental and coastal locations but is weak at the ocean site. The greater

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Jonathan Zawislak and Edward J. Zipser

the two measures of AEW activity—the synoptic-scale wave trough and convectively generated subsynoptic-scale vorticity centers—are not necessarily related. Rather, coherent subsynoptic-scale structures can exist without the presence of a strong AEW, and synoptic-scale AEWs can exist without coherent subsynoptic-scale structures. Likewise, Reed et al. (1988) and Thorncroft and Hodges (2001) caution on using vorticity maxima to characterize wave activity over land in weak or multicentered waves

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John Molinari and David Vollaro

parameters used in this study support the possible existence of supercells in tropical cyclones, especially in the downshear right quadrant outside of the 100-km radius. Supercells have been observed in tropical cyclones after landfall (e.g., McCaul et al. 2004 ) and near land ( Baker et al. 2009 ). Radar data are needed to confirm whether such cells occur in tropical cyclones over open ocean. Many questions about convection in tropical cyclones remain unanswered. What is the range of scales of

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Zhuo Wang, M. T. Montgomery, and T. J. Dunkerton

calculated explicitly at the grid scale. Other physics parameterizations used include the WRF single-moment, six-class microphysics ( Hong and Lim 2006 ), Yonsei University (YSU) PBL scheme, Noah land surface scheme, Rapid Radiative Transfer Model (RRTM) longwave radiation scheme, and Dudhia shortwave radiation scheme. To test the robustness of the results reported in Part I , sensitivity tests with different model physics and initial conditions were conducted. To save computational time, all

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Chanh Q. Kieu and Da-Lin Zhang

example, Bosart and Sanders (1981) , Harr and Elsberry (1996) , Harr et al. (1996) , and Zhang and Bao (1996a , b ) showed TCG as induced by single well-defined MCVs associated with mesoscale convective systems (MCSs). Using satellite and research aircraft data, Ritchie and Holland (1997 , hereafter RH97 ) studied the interaction of midlevel MCVs with a low-level large-scale trough in the formation of Typhoon Irving (1992). They found that the initial interaction of the low-level trough and a

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Syed Ismail, Richard A. Ferrare, Edward V. Browell, Gao Chen, Bruce Anderson, Susan A. Kooi, Anthony Notari, Carolyn F. Butler, Sharon Burton, Marta Fenn, Jason P. Dunion, Gerry Heymsfield, T. N. Krishnamurti, and Mrinal K. Biswas

. Karyampudi and Pierce (2002) found that the SAL had a positive influence on the genesis of two Atlantic storms through enhancement of baroclinic instability. The SAL can also influence cloud microphysical properties and act as a source of cloud condensation nuclei (CCN) enhancing convective intensity ( Khain et al. 2005 ; Jenkins et al. 2008 ). Recent studies ( Jenkins and Pratt 2008 ; Twohy et al. 2009 ) using data collected during NAMMA postulated that SAL dust particles can act as CCN, which in

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Scott A. Braun, Michael T. Montgomery, Kevin J. Mallen, and Paul D. Reasor

-theory surface-layer scheme ( Zhang and Anthes 1982 ; Skamarock et al. 2005 ), the Noah land surface scheme ( Chen and Dudhia 2001 ), the Kain–Fritsch cumulus scheme ( Kain and Fritsch 1990 , 1993 ; Skamarock et al. 2005 ) on the 54- and 18-km grids only and calculated every time step, and the WRF single-moment six-class cloud microphysics ( Hong et al. 2004 ) on all grids. Radiative processes are calculated every 5 min on the 54- and 18-km grids and 2 min on the 6- and 2-km grids using the Rapid

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Edward K. Vizy and Kerry H. Cook

wave, Tropical Storm Debby, so those parameters were selected for use here. Parameterizations chosen include the Purdue–Lin microphysics scheme, new Kain–Fritsch cumulus convection scheme; Monin–Obukhov surface layer scheme; unified National Centers for Environmental Prediction (NCEP), Oregon State, Air Force, Hydrologic Research Laboratory of the National Weather Service (NOAH) land surface model ( Chen and Dudhia 2001 ); the NCAR CAM radiation parameterization; and the Yonsei University planetary

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