The Local Group L-Band Survey (LGLBS) provides some of the highest spatial and spectral resolution HI data available for nearby star-forming galaxies, enabling studies of neutral gas structure on ~10–20 pc scales. Using these data, we investigate the cold neutral medium (CNM), a key phase of the interstellar medium that regulates the transition from atomic to molecular gas and therefore plays a central role in star formation and galaxy evolution. Neutral hydrogen (HI) absorption offers a direct probe of CNM properties, allowing measurements of optical depth and spin temperature in a wide range of environments. We present new HI absorption results for IC10 and M33, which span low-metallicity regimes (~0.27 Z☉ and ~0.4 Z☉, respectively). This enables a comparative study of how metallicity and local feedback influence CNM structure and the atomic-to-molecular transition. In IC10, we detect three CNM absorption components: two located near the optical centre in front of active star-forming regions, and one along the edge of an HI shell. These components show broad line widths and, in two cases, elevated optical depths compared to Local Group dwarfs, indicating a turbulent, feedback-driven cold medium. In M33, we identify nine HI absorption systems distributed across spiral arm and interarm environments. Three arise against internal HII regions, while the remainder are seen against bright background radio quasars. Ongoing analysis combines absorption and emission data to quantify environmental variations in CNM properties. Together, these galaxies provide complementary constraints on how metallicity and feedback regulate small-scale CNM structure and star formation.
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