Doppler radar, airborne, and sounding data are used to describe the structure of an exceptionally vigorous narrow cold-frontal rainband (NCFR). A combined thermodynamic and cloud microphysical retrieval technique is used to derive the pressure perturbations and buoyancy in balance with the flow field in the vicinity of the NCFR. The NCFR was triggered by a well-defined cold front that penetrate...

The Canadian Centre for Climate Modelling and Analysis atmospheric general circulation model (AGCM4) is used to study the role of shallow convection in the hydrologic and energy cycles of the atmosphere. Sensitivity tests with AGCM4 show a marked effect of the parameterization of shallow convection in the model. In particular, including the parameterization of shallow convection produces consid...

[1] This paper focuses on the relation between local sea surface temperature (SST) and convective precipitation fraction and stratiform rainfall area from radar observations of precipitation, using data from the Kwajalein atoll ground-based radar as well as the precipitation radar on board the TRMM satellite. We find that the fraction of convective precipitation increases with SST at a rate of ...

[1] Variability of the cloud population in the central equatorial Indian Ocean was observed in the context of the Madden-Julian Oscillation (MJO) during the Dynamics of the MaddenJulian Oscillation (DYNAMO) and Atmospheric Radiation Measurement Madden-Julian Investigation Experiment (AMIE) field campaigns. Radar observations from the polarimetric S-band radar on Addu Atoll in theMaldives charac...

A simplified intermediate model for analyzing and parameterizing convectively coupled tropical waves is introduced here. This model has two baroclinic modes of vertical structure: a direct heating mode and a stratiform mode. The key essential parameter in these models is the area fraction occupied by deep convection, sc. The unstable convectively coupled waves that emerge from perturbation of a...

The new one-dimensional forecast model PAFOG for radiation fogs and low level stratiform clouds will be presented. The aim of the model is to improve the local visibility forecast on airports and other traffic locations where fog and low level stratus frequently occur. PAFOG has been developed on the basis of the microphysical fog model MIFOG of Bott et al. (1990). To obtain a numerically effic...

[1] Five hours of detailed observations of the asymmetric bow-echo mesoscale convective system on 11–12 June 2000 during the STEPS project are presented. Data sources included polarimetric and Doppler radars, a VHF lightning mapper, and the National Lightning Detection Network. Nearly every (99%) VHF lightning source occurred within 10 km of the convective line. Charge identification within the...

The North East (NE) region of India is prone to severe thunderstorm during pre monsoon period. These premonsoon precipitations are measured at Guwahati (26 17’ N, 91 77’ E) using a laser based particle size and velocity (PARSIVEL) disdrometer from 15 April to 31 May 2010 under a national field campaign named Severe Thunderstorm Observational and Regional Modeling (STORM). For the improved under...

The sensible heat budget of a large-scale area containing an idealized tropical cloud cluster is analyzed. The cluster is assumed to have spatial dimensions and precipitation rates typical of observed cloud clusters. In its early stages of development the idealized cluster consists of isolated deep precipitating convective cells, or "hot towers." A simple model using the assumed precipitation r...