The time-scales associated with the various stages of the star formation process remain poorly constrained .
This includes the earliest phases of star formation , during which molecular clouds condense out of the atomic interstellar medium .
We present the first in a series of papers with the ultimate goal of compiling the first multi-tracer timeline of star formation , through a comprehensive set of evolutionary phases from atomic gas clouds to unembedded young stellar populations .
In this paper , we present an empirical determination of the lifetime of atomic clouds using the Uncertainty Principle for Star Formation formalism , based on the de-correlation of H \alpha and H i emission as a function of spatial scale .
We find an atomic gas cloud lifetime of 48 \substack { +13 \ -8 } Myr .
This timescale is consistent with the predicted average atomic cloud lifetime in the LMC ( based on galactic dynamics ) that is dominated by the gravitational collapse of the mid-plane ISM .
We also determine the overlap time-scale for which both H i and H \alpha emission are present to be very short ( t _ { \text { over } } < 1.7 Myr ) , consistent with zero , indicating that there is a near-to-complete phase change of the gas to a molecular form in an intermediary stage between H i clouds and H ii regions .
We utilise the time-scales derived in this work to place empirically determined limits on the time-scale of molecular cloud formation .
By performing the same analysis with and without the 30 Doradus region included , we find that the most extreme star forming environment in the LMC has little effect on the measured average atomic gas cloud lifetime .
By measuring the lifetime of the atomic gas clouds , we place strong constraints on the physics that drives the formation of molecular clouds and establish a solid foundation for the development of a multi-tracer timeline of star formation in the LMC .