Lightning and Rainfall Characteristics in Elevated vs. Surface Based Convection in the Midwest that Produce Heavy Rainfall

Abstract

There are differences in the character of surface-based and elevated convection, and one type may pose a greater threat to life or property. The lightning and rainfall characteristics of eight elevated and eight surface-based thunderstorm cases that occurred between 2007 and 2010 over the central Continental United States were tested for statistical differences. Only events that produced heavy rain (>50.8 mm·day −1 ) were investigated. The nonparametric Mann-Whitney test was used to determine if the characteristics of elevated thunderstorm events were significantly different than the surface based events. Observations taken from these cases include: rainfall-lightning ratios (RLR) within the heavy rain area, the extent of the heavy rainfall area, cloud-to-ground (CG) lightning flashes, CG flashes·h −1 , positive CG flashes, positive CG flashes·h −1 , percentage of positive CG flashes within the heavy rainfall area, and maximum and mean rainfall amounts within the heavy rain area. Results show that elevated convection cases produced more rainfall, total CG lightning flashes, and positive CG lightning flashes than surface based thunderstorms. More available moisture and storm morphology explain these differences, suggesting elevated convection is a greater lightning and heavy rainfall threat than surface based convection.

Dynamic and Thermodynamic Factors Associated with Different Precipitation Regimes over South China during Pre-Monsoon Season

“…Different types of convection even lead to different levels of threat to life and property. As revealed by Kastman et al [57], compared to surface based convection, elevated convection favors more severe lightning and heavier rainfall. CAPE is used to evaluate the convective potential for the atmosphere, i.e., the energy with which the air parcel could keep rising when there are no external forces [58][59][60].…”

An investigation of atmospheric rivers impacting heavy rainfall events in the North‐Central Mississippi River Valley

“…This value must have been maintained for at least 24 hr as it impacted the study region (Figure ) and must have been associated with heavy (>50.8 mm) rainfall events. These events are typically associated with flooding events across the region of study (Kastman et al ., ; ), and represent the largest 24‐hr rainfall events during the study period (two events per year). Using this criterion, 15 AR events were identified over the 15‐year period and this result is consistent with those used by many recent studies (see Debbage et al ., ).…”

“…Since the onset of the remote sensing era, there have been many advances in the analysis and forecasting of high‐impact weather, especially heavy precipitation events (e.g., Stephens and Kummerow, ; Bosart et al ., ; Kastman et al ., ; ). There is still much work needed, however, in order to understand better the dynamics of these atmospheric phenomena (e.g., Lupo et al ., ; Kastman et al ., ; ). The purpose of this study is to garner a better understanding for the antecedent factors that contribute to or are associated with heavy rainfall events across the North‐Central Mississippi River Valley.…”

Dynamic Ensemble Analysis of Frontal Placement Impacts in the Presence of Elevated Thunderstorms during PRECIP Events

“…The study below will analyze convective environments that show both purely and hybrid elevated convective environments [18]. While the general hazards of thunderstorms are similar for both environments [5,6], contrasting the evolution of the environment and differing characteristics of the systems that evolve are important findings of this study.…”

“…Elevated thunderstorm complexes pose numerous threats and are well established as producers of heavy rainfall [1][2][3][4], flash flooding [3][4][5], and cloud-to-ground lightning flashes [4,6,7]. Furthermore, these elevated complexes are suspected of disrupting synoptic boundary location and movement [8,9] as cold pools from convection interact with surface boundaries.…”