Downloaded 10/04/21 05:16 PM UTC 6674 JOURNAL of CLIMATE VOLUME 27 Directly Proportional to the Vertical Gradient of the Heat- More Elevated Divergence Profiles
1SEPTEMBER 2014 H O M E Y E R E T A L . 6673 Assessing the Applicability of the Tropical Convective–Stratiform Paradigm in the Extratropics Using Radar Divergence Profiles CAMERON R. HOMEYER National Center for Atmospheric Research,* Boulder, Colorado COURTNEY SCHUMACHER Department of Atmospheric Sciences, Texas A&M University, College Station, Texas LARRY J. HOPPER JR. Department of Atmospheric Sciences, School of Sciences, University of Louisiana at Monroe, Monroe, Louisiana (Manuscript received 16 September 2013, in final form 15 May 2014) ABSTRACT Long-term radar observations from a subtropical location in southeastern Texas are used to examine the impact of storm systems with tropical or extratropical characteristics on the large-scale circulation. Clima- tological vertical profiles of the horizontal wind divergence are analyzed for four distinct storm classifications: cold frontal (CF), warm frontal (WF), deep convective upper-level disturbance (DC-ULD), and nondeep convective upper-level disturbances (NC-ULD). DC-ULD systems are characterized by weakly baroclinic or equivalent barotropic environments that are more tropical in nature, while the remaining classifications are representative of common midlatitude systems with varying degrees of baroclinicity. DC-ULD systems are shown to have the highest levels of nondivergence (LND) and implied diabatic heating maxima near 6 km, whereas the remaining baroclinic storm classifications have LND altitudes that are about 0.5–1 km lower. Analyses of climatological mean divergence profiles are also separated by rain regions that are primarily convective, stratiform, or indeterminate. Convective–stratiform separations reveal similar divergence char- acteristics to those observed in the tropics in previous studies, with higher altitudes of implied heating in stratiform rain regions, suggesting that the convective–stratiform paradigm outlined in previous studies is applicable in the midlatitudes.
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