Recent forecasts from National Weather Service and other models indicate overnight lows in Los Angeles for September 26 ranging from the upper 60s to low 70s, with substantial spread across ensemble runs due to variable marine layer depth and cloud cover. The marine layer—a shallow, cool, moist air mass advected from the Pacific—typically moderates minimum temperatures through radiative cooling and fog, but its inversion strength and onshore flow can shift rapidly with subtle changes in 850 mb heights or weak offshore components. Late-September climatology favors occasional weakening of the sea breeze, allowing slightly warmer downslope mixing, while persistent stratus keeps readings closer to seasonal normals near 62°F. This genuine uncertainty in boundary-layer processes and model resolution of local topography explains the tightly clustered market-implied odds across adjacent ranges, with new model guidance and evening observations likely to refine the outcome before resolution.