We analyze how extreme rainfall intensities in the Eastern United States depend on temperature T, dew point temperature Td, and convective available potential energy CAPE, in addition to geographic sub-region, season, and averaging duration. When using data for the entire year, rainfall intensity has a quasi Clausius-Clapeyron (CC) dependence on T, with super-CC slope in a limited temperature r...

Lake-effect snowstorms in northern Utah and western New York with and without lightning/thunder are examined. Lake-effect snowstorms with lightning have significantly higher temperatures and dewpoints in the lower troposphere and significantly lower lifted indices than lake-effect snowstorms without lightning. In contrast, there is little difference in dewpoint depressions between events with a...

Abstract Convective self-aggregation refers to a phenomenon in which random convection can self-organize into large-scale clusters over an ocean surface with uniform temperature cloud-resolving models. Previous literature studies convective aggregation primarily by analyzing vertically integrated (VI) moist static energy (MSE) variance. That is the global MSE variance, including both local vari...

A linear stability analysis of rotating Boussinesq flows including shear, μ-gradients and radiation losses leads to modification of the classical Ledoux criterion for convective equilibrium. The role of shear in spreading the radial extent of the convective layers is briefly investigated, and we found that some effects may be expected in the latest nuclear evolutionary stages of massive stars, ...

[1] This paper explores the impact of the physical parameterization suite on the evolution of an idealized tropical cyclone within the National Center for Atmospheric Research’s (NCAR) Community Atmosphere Model (CAM). The CAM versions 3.1 and 4 are used to study the development of an initially weak vortex in an idealized environment over a 10‐day simulation period within an aqua‐planet setup. ...

On 10 July 2006, during the Special Observation Period (SOP) of the African Monsoon Multidisciplinary Analysis (AMMA) campaign, a small convective system initiated over Niamey and propagated westward in the vicinity of several instruments activated in the area, including the Massachusetts Institute of Technology (MIT) C-band Doppler radar and the Atmospheric Radiation Measurement (ARM) mobile f...

[1] Convective available potential energy (CAPE) is shown to increase rapidly with warming in simulations of radiativeconvective equilibrium over a wide range of surface temperatures. The increase in CAPE implies a systematic deviation of the thermal stratification from moist adiabatic that is non-negligible at high temperatures. However, cloud buoyancy remains much smaller than what CAPE would...

Previous studies have established that sea surface temperature anomalies (SSTAs) in the tropical Pacific and Atlantic are the main forcing of the interannual variation of the wet season onsets in the Amazon. However, this variation appears to be complex and not uniquely determined by SSTAs. What causes such a complexity and to what extent the interannual variation of the wet season onsets is pr...

The observed convective adjustment time (CAT) associated with Madden–Julian Oscillation (MJO) precipitation is found to vary significantly in space. Here, we investigate the effect of different spatial distributions of CAT on MJO precipitation based on the frictional coupled dynamics moisture (FCDM) model. The results show that a large value of CAT tends to decrease the frequency and growth rat...