Atmospheric stability sets maximum moist heat and convection in the midlatitudes

TL;DR

This paper develops a theoretical framework linking atmospheric stability, specifically low-level inversions, to the maximum potential intensities of extreme moist heat and severe convection in midlatitude regions, enhancing understanding and modeling of these compound weather events.

Contribution

It introduces a novel theoretical approach that connects atmospheric stability, especially low-level inversions, to the potential severity of extreme heat and convective storms in midlatitudes.

Findings

Extreme moist heat and severe convection often co-occur in midlatitudes.

Low-level inversions are critical in determining the maximum intensity of these events.

The framework improves understanding and modeling of compound extreme weather risks.

Abstract

Extreme near-surface moist heat and severe convective storms are among the leading causes of weather-related damages worldwide. Here, we show that episodes of extreme moist heat and severe convection frequently co-occur across midlatitude land regions, and develop a theoretical framework that links their maximum potential intensities to preexisting low-level energy inversions. By accounting for the stored-energy nature of midlatitude severe convection, where moist heat and atmospheric instability accumulate before convection initiates, our work advances the understanding of convective constraints on extreme heat events. The theory identifies low-level inversions as a critical factor shaping compound extreme heat and convective weather risks, and offers a pathway for improving the modeling and future projection of these events.