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Climate change induces significant changes in storm characteristics, particularly for short‐duration extreme storms (heavy rain features), impacting their intensity and spatio‐temporal distribution. Although alterations in precipitation intensity are well documented, past studies examining changes in spatio‐temporal distribution of storms (storm rainrates) were region‐specific and focused on isolated aspects of change in space or time, eluding a comprehensive understanding of the precise nature and extent of these changes. Bridging this gap, this study introduces a novel grid‐based measure of storm homogeneity, "spatio‐temporal homogeneity" metric and investigates the global patterns of change in combined spatio‐temporal characteristics of extreme storms. Analyzing the 30 min × 0.1° × 0.1° resolution Global Precipitation Measurements, the study finds that extreme storms are shrinking in both space and time due to rising surface air temperatures, predominantly in tropics. In contrast, temperate regions experience expanded extreme storms with increasing temperatures. The study also identifies a global trend toward more front‐loading in storms with rising temperatures, driven by a substantial increase in tropics and southern temperate regions. Conversely, storms in northern temperate regions become slightly more rear‐loaded as temperature increases. Furthermore, the study finds that characteristics of short–duration storms (6–12 hr) are more sensitive to temperature changes. Overall, this study contributes valuable insights into the global spatio‐temporal changes of extreme storms, highlighting regions most susceptible to alterations in storm patterns due to climate change. These findings are essential for developing effective adaptation strategies and flood management practices to cope with the changing nature of extreme storms in a warming climate. Plain Language Summary: Extreme rainfall can lead to floods, affect ecosystems, and challenge water management. How intense the rain is, how wide an area it covers, and how long it lasts are key factors in determining flood risk. Additionally, whether the rainfall starts strong and tapers off (front‐loaded) or begins gently and then fades quickly (rear‐loaded)—also plays a role. As the climate changes, it's crucial to understand how these extreme storm characteristics are evolving to better prepare for the future. This study introduces a new way to measure changes in the size and duration of extreme storms in response to rising temperatures worldwide. It also examines whether warmer temperatures make storms more likely to start strong and taper off or the opposite. The findings show that in tropical regions, extreme storms are becoming effectively shorter and covering effectively smaller areas as temperatures increase. Conversely, in temperate regions, storms are lasting longer and covering effectively larger areas. Additionally, storms in areas below 30°N are tending toward more front‐loading, while those above 30°N are becoming more rear‐loaded. This research helps us understand how warming temperatures are changing storm patterns and can inform better flood preparedness and water management strategies. Key Points: Introduces Spatio‐Temporal Homogeneity metric to effectively track comprehensive changes in storm characteristics across both space and timeRising temperature causes "spatio‐temporally peakier" storms in tropics, intense precipitation burst in smaller area over shorter durationRising temperature leads to more front‐loading in storms, notably in tropics and southern temperate regions, increasing flash flood risk [ABSTRACT FROM AUTHOR]

The signal of temperature change has emerged from background variations in most tropical regions in boreal summer over decadal‐centennial timescales but not in northern‐central India (NCI). In this study, we investigated the reason for the limited temperature change in NCI. We found that internal variability, largely caused by the Interdecadal Pacific Oscillation (IPO) on a ∼20‐year timescale, has the potential to mask the temperature change signal. Besides, local response to external forcing, linked to non‐greenhouse gas (GHG) forcings, strongly overrides GHG warming in NCI, which results in little trend in the temporal evolution of external variability. The internal variability related to IPO and the limited warming arising from the competition between multiple forcings result in the smallest signal‐to‐noise ratio and thus, the temperature change signal fails to emerge from the background variations. Plain Language Summary: Earth's surface has warmed considerably since 1850s, which can be largely attributed to anthropogenic greenhouse gas emissions. When human activities (e.g., greenhouse gas emissions) cause the local temperature change to exceed the inherent variation of the climate system, the region will face more extreme climate events. Although temperature has experienced warming almost all around the globe, here we show that surface air temperature in boreal summer in northern‐central India has not gone through significant changes. The timing of transition is important for policymakers. Thus, we analyzed the reasons for this and show that it reflects the combined effects of natural processes and local anthropogenic forcings. Key Points: The external forcing exhibits a cooling trend in northern‐central India (NCI), whereas most global regions have warmed considerablyCooling effects of non‐greenhouse gas forcings that override global warming lead to a cooling trend in NCIThe internal variability related to the Interdecadal Pacific Oscillation and the limited warming cause the smallest signal‐to‐noise ratio [ABSTRACT FROM AUTHOR]