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Showing 1 to 20 of 43 for “"updrafts"”.
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Examining the role of deep convective updrafts in QLCS tornadogenesis using observations and real-world modeling
Submission original under an indefinite embargo labeled 'Open Access'. The submission was exported from vireo on 2023-12-04 without embargo terms
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THE OBSERVED VARIATION OF COHERENT UPDRAFT OBJECTS WITH HEIGHT IN THE CONVECTIVE BOUNDARY LAYER
… analyze the properties of ~120,000 coherent CBL updrafts recorded with a network of five Doppler lidars in Oklahoma, USA on days with clear and cumulus topped boundary layers. We present the composite evolution of these updraft objects as a function of height, which reveal a mixture of plume-like …
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An investigation of the development of supercells in the Indiana and Ohio tornado outbreak of 24 August 2016 using a WRF model simulation
… indicate that parcels entering the multicellular updrafts before 1530 UTC originate above 1 km, meaning that the convection is elevated. As diurnal heating progresses, more near-surface parcels enter the multicellular updrafts, each of which move atop convective outflow and weaken. Since nearly …
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Structure of an east coast cyclone derived from airborne radar and model diagnostics
… convection observed near cloud top exhibited updrafts of 2 to 3.5 m s-1 and was often located within layers of WRF modeled potential instability. Beneath the elevated convection were many enhanced reflectivity fall streaks that were shaped by the vertical wind shear profile. Turbulent features …
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Investigation of the structure of natural orographic clouds embedded within atmospheric river type flow over the Payette Mountains in Idaho
… seeding missions. Past research has shown that updrafts within orographic clouds are required for SLW to be present. Using the WCR observations, supplemented by simulations using the Weather Research and Forecasting model, the nature of cloud updrafts within the Payette Mountains were …
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Rain Formation in Shallow Tropical Convection
… on the results by the observed evolution of the updrafts, the calculations showed that the process of rain formation in warm convective clouds is simple and efficient, provided that giant and ultragiant CCN are present near cloud base. While more complex processes leading to drop spectra …
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Latent heating and mixing due to entrainment in tropical deep convection
… rates in the convective inflow regions and updrafts examined here, the residual term is treated as an approximate representation of mixing within these regions. The simulations demonstrate that mixing with dry air decreases equivalent potential temperature along ascending trajectories below …
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Interaction of an upper-tropospheric jet with a squall line originating along a cold frontal boundary
… air from the boundary layer via convective updrafts is shown to significantly decelerate jet-level flow. The convective updrafts are also found to tilt baroclinically generated horizontal shear into the vertical, contributing to the generation of counter rotating ribbons of vertical …
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Estimating midlevel updraft characteristics and severe weather intensity through the lens of overshooting tops
… observations of (overshooting tops) OTs and updrafts collected in three cases during the RELAMPAGO field campaign in Córdoba province, Argentina. The RELAMPAGO data revealed that different convective morphologies had different OT characteristics, with long-lived, large OTs found in …
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Understanding tornado intensity in supercells and quasi-linear convective systems
… vortex intensity. Both stronger and wider updrafts produce stronger near-surface rotation much more quickly than their weaker, narrower counterparts. Because of the linkages in real storms between the storm updraft and cold pool characteristics, it is determined that the storm updraft …
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Free convection and turbulent fluxes over complex terrain
… turbulent scales – typical for thermal updrafts in the CBL – already close to the ground. An ensemble and time mean analysis of the simulated flow field in the valley further confirmed that the Sodar/RASS was located preferably in an updraft region during FCCs. In a CBL over flat …
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How does terrain influence the upscale convective growth of orographic deep moist convection?
… the vertical wind shear profile prompting wider updrafts in higher terrain supercells. These wider supercell updrafts were accompanied by greater vertical mass flux, wider and stronger downdrafts, and deeper cold pools, promoting more rapid upscale convective growth.
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Numerical simulations of mesoscale convective systems: techniques for comparison with observations and a high resolution analysis of flow patterns in the convective region and transition zone of a simulated mcs
… were found to still affect the convective updrafts in addition to their immediate environment, including the horizontal velocity and temperature fields. The convective updraft was found to be highly unsteady, frequently changing between one or two coherent primary updrafts and a series of …
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Assessment of Convectively Generated Tropical Cirrus in Global Storm-Resolving Models
… frequent overshooting convection whose strongest updrafts humidify the TTL and are its main source of frozen water. Inter-model differences in cloud properties and convective injection exceed differences between land and ocean regions in each model. We argue that global storm-resolving mod- els …
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The influence of primary nucleation and rime splintering on ice number concentrations in southern ocean cumuli
… ice (over 100 per Liter) tend to have multiple updrafts, and also possess the necessary characteristics for secondary ice production by rime splintering (graupel, cloud droplets exceeding 25 μm diameter, and occurrence within the -3 to -9 C temperature range). High-resolution, 3D idealized …
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Controls of updraft size, cold pool characteristics, and potential tornado intensity in supercell thunderstorms
… should more readily form from wider rotating updrafts. This hypothesis is tested using idealized simulations, which reveal strong correlations between updraft width and low-level vorticity that support this hypothesis. These simulations are also used to explore how quantifications of …
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Analysis of vertical velocities and elevated instability in the comma-head of continental winter cyclones
… to the tropopause. The stronger convective updrafts ranged from 2 to 7 m s-1 and downdrafts from -2 to -6 m s-1. The horizontal scale of the convective cells was ~5 km. The poleward zone of the comma head was characterized by deep stratiform clouds topped by cloud top generating cells that …
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The influence of longwave cloud-top cooling on marine stratocumulus cloud transitions
… are largely surface-based cumulus-like updrafts. The simulations with stronger ΔFn undergo this transition sooner and exhibit higher cloud-top heights, stronger overall turbulence, increased precipitation, and a better-sustained cloud cover. Increases in precipitation with stronger …
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Dependence of tropical cirrus clouds on sea surface temperature and consequences for the Archean climate
… classification of cloudy regions into convective updrafts and anvil, the use of cloud weighted SST, and the truncation and sampling error with respect to the evolution of mesoscale convective systems. All of these contribute to some extent to the weakness of signal. We show that the coarse …
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Determining Best Method For Estimating Observed Level Of Maximum Convective Detrainment Based On Radar Reflectivity
… when applied to convective systems with mature updrafts, and is most accurate with convective lines and isolated cells. A time lag is present in the reflectivity based LMD compared to the vertical mass divergence based LMD because the reflectivity method is dependent on anvil growth.</p> <p>This …
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