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Patrick Duran and John Molinari

possible that a vertical grid spacing even smaller than 250 m is necessary to resolve cloud-top radiative tendencies. Meanwhile below the tropopause, time-mean radiative warming was present between the 30- and 160-km radii within the cirrus canopy. The existence of radiative cooling overlying radiative warming in this region led to radiatively forced destabilization at and below the tropopause, as was depicted in Fig. 7d . Beneath the warming layer existed a region of forcing for stabilization, while

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David R. Ryglicki, Joshua H. Cossuth, Daniel Hodyss, and James D. Doyle

-level forcing mechanism), and this study identifies and quantifies a set of key common features for this class of TCs. The analyses in this study primarily rely on satellite observations, since these data typically provide the most complete spatial and temporal coverage over the storms, given that aircraft observations of TCs are rare in the eastern North Pacific (EPAC) and western Pacific (WPAC; Knabb et al. 2008 ). Without in situ reconnaissance data, intensity estimations and analyses are primarily

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Benjamin C. Trabing, Michael M. Bell, and Bonnie R. Brown

) . Cloud-free radiative cooling could also be a potential mechanism for explaining the intensity differences between the Fullrad and Nightonly simulations ( Gray and Jacobson 1977 ). In the Nightonly simulations the enhanced cloud-free environmental subsidence driven by longwave cooling in the outer environment could force stronger inflow into the TC; however, no substantial differences were present in the outer-core radiative cooling rates over 24-h means (not shown). Due to the short time scale of

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David R. Ryglicki, James D. Doyle, Yi Jin, Daniel Hodyss, and Joshua H. Cossuth

-modulated convective asymmetry (TCA). TCAs, as diagnosed by cloud-top temperatures colder than −70°C, are cloud structures that are responsible for approximately 10 000–15 000-km 2 changes in cloud cover, that expand upshear, and, most importantly for the purposes of this study, that appear with periods between 4 and 8 h. A series of numerical simulations in this second part are analyzed to quantify further the dynamics and characteristics, including the vertical structure, of this class of TCs that undergo RI in

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Russell L. Elsberry, Eric A. Hendricks, Christopher S. Velden, Michael M. Bell, Melinda Peng, Eleanor Casas, and Qingyun Zhao

scan a full Earth disk at 10-min intervals. The spatial resolution is also enhanced to 0.5 km for band 3 in the visible wavelength, and the two other visible bands and band 4 in the near-infrared have 1-km resolution. Two other near-infrared bands and all infrared bands have a spatial resolution of 2 km. The infrared band 11 is used for detection of thin ice cloud such as is often found at the edge of the TC cirrus outflow, and infrared band 16 is used for cloud-top height assignment. The three

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David R. Ryglicki, James D. Doyle, Daniel Hodyss, Joshua H. Cossuth, Yi Jin, Kevin C. Viner, and Jerome M. Schmidt

ventilating TCs, inducing a potential vorticity–related spinup, and outright shearing of the TC, depending on the proximity of the upper-level synoptic forcing. Vertical wind shear (VWS) is generally a negative influence on TC intensification ( Merrill 1988b ; Wang and Wu 2004 ). Recent studies on wind shear’s negative effects have focused on the thermodynamic effects of VWS, such as the midlevel ventilation ( Tang and Emanuel 2010 ; Tang and Emanuel 2012 ; Ge et al. 2013 ) or the flushing of the

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Patrick Duran and John Molinari

), the coldest temperature, −86°C, was observed a few hundred meters above the highest cloud tops ( Waco 1970 ). Very near the storm center, the temperature at 16.5-km altitude increased from −86° to −77°C over a horizontal distance less than 30 km as the aircraft approached the storm center [see Fig. 2 “Run 2” in Waco (1970) ]. This strong inward temperature increase was likely associated with an intense upper-tropospheric warm core within and near Beulah’s eye. The presence of a warm core in the

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Xu Lu and Xuguang Wang

originally designed under a clear-sky assumption where the free atmosphere has little diffusion. Therefore, K m is always set to zero at the PBL top and the K m above the PBL is always following the clear-sky profiles in the HWRF PBL scheme. But this assumption is not suitable for the deep convection, such as the eyewall or spiral rainbands, where in-cloud turbulence creates large mixing above the PBL. Zhu et al. (2018) proposed a modified turbulent mixing parameterization scheme that replaces the

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Peter Black, Lee Harrison, Mark Beaubien, Robert Bluth, Roy Woods, Andrew Penny, Robert W. Smith, and James D. Doyle

near the wingtips of the aircraft allow signals to be received during aircraft turns when the large wing would result in shadowing of the two belly antennas and receivers. The HDSS also carries two cameras to record dropsonde ejection: one aft of the drop tubes facing forward and one forward of the drop tubes facing aft. These cameras also were used to document cloud structures ahead of and behind the aircraft ( Fig. 16 ). The mission monitor display for the WB-57 was used to maintain situational

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William A. Komaromi and James D. Doyle

hypothesis, referred to as active outflow , is that a source of upper-level forcing that acts to accelerate or otherwise enhance the TC outflow can ultimately drive changes in the strength or structure of the vortex below (e.g., Sadler 1976 ; Holland and Merrill 1984 ; Nong and Emanuel 2003 ). Here, we do not seek to determine whether outflow is more likely to be passive or active. Instead, we explore the hypothesis that active outflow may contribute to TC intensification under the right set of

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