The initiation of second‐generation convective storms by the cold pools of first‐generation storms is known to depend on cold pool characteristics such as depth and speed. It is not clear, however, how these characteristics relate back to the convective storm components and, in turn, to the environment. Here we investigate the hypothesis that wider updraft cores result in wider downdraft cores, which subsequently lead to the development of deeper cold pools that are more likely to initiate new convection. This hypothesis is addressed using a large set of idealized numerical simulations of highly organized convective storms, specifically, supercells. Quantifications of the convective components show strong interrelationships between updraft area, downdraft area, and cold pool depth, thus supporting our primary hypothesis. These interrelationships are highly sensitive to the parcel buoyancy and vertical wind shear, with large convective available potential energy, strong wind shear, and a deep mixed layer ultimately contributing to the deepest (and strongest) cold pools. Diagnoses of the forcings of vertical accelerations show that draft width, and therefore cold pool depth, are initially influenced by the buoyancy and linear dynamic forcings, but thereafter are controlled mostly by the nonlinear dynamic forcings. These results, overall, have implications on the development (or improvement) of cold pool parameterizations in weather and climate models.

Strong to violent tornadoes cause a disproportionate amount of damage, in part because the width and length of a tornado damage track are correlated to tornado intensity (as now estimated through enhanced Fujita scale ratings). The tendency expressed in the observational record is that the most intense tornadoes are often the widest. Herein the authors explore the simple hypothesis that wide intense tornadoes should form more readily out of wide rotating updrafts. This hypothesis is based on an application of Kelvin’s circulation theorem, which is used to argue that the large circulation associated with a wide intense tornado is more plausibly associated with a wide mesocyclone. Because a mesocyclone is, strictly speaking, a rotating updraft, the mesocyclone width should increase with increasing updraft width. A simple mathematical model that is quantified using observations of mesocyclones supports this hypothesis, as do idealized numerical simulations of supercellular thunderstorms.

Recent work established strong links between storm updraft width and the tornado intensity, suggesting that updraft width could be used to gauge potential tornado intensity. It was also posited that overshooting top area (OTA) could be used as an analog for updraft width and, thus, as a means to assess potential tornado intensity in observed storms. The implementation of new high‐resolution GOES‐R series satellites presents a unique opportunity to investigate these findings in severe weather observations. Herein, a method using GOES‐16 longwave infrared satellite data to quantify OTA of tornadic storms is explored. A comparison between observed tornado strength and OTA yields a strong correlation (R2 = 0.54). These results show the potential of these quantifications to be used with real‐time observations of tornadic storms, irrespective of storm mode, seasonality, or geographic location, allowing forecasters to determine which storms pose the highest risk to life and property.

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Although tornadoes produced by quasi-linear convective systems (QLCSs) generally are weak and short-lived, they have high societal impact due to their proclivity to develop over short time scales, within the cool season, and during nighttime hours. Precisely why they are weak and short lived is not well understood, although recent work suggests that QLCS updraft width may act as a limitation to tornado intensity. Herein, idealized simulations of tornadic QLCSs are performed with variations in hodograph shape and length as well as initiation mechanism to determine the controls of tornado intensity. Generally, the addition of hodograph curvature in these experiments results in stronger, longer-lived tornadic like vortices (TLVs). A strong correlation between low-level mesocyclone width and TLV intensity is identified (R2 = 0.61), with a weaker correlation in the low-level updraft intensity (R2 = 0.41). The tilt and depth of the updraft are found to have little correlation to tornado intensity. Comparing QLCS and isolated supercell updrafts within these simulations, the QLCS updrafts are less persistent, with the standard deviations of low-level vertical velocity and updraft helicity to be approximately 48% and 117% greater, respectively. A forcing decomposition reveals that the QLCS cold pool plays a direct role in the development of the low-level updraft, providing the benefit of additional forcing for ascent while also having potentially deleterious effects on both the low-level updraft and near-surface rotation. The negative impact of the cold pool ultimately serves to limit the persistence of rotating updraft cores within the QLCS.