Electrochemical Additive Manufacturing (ECAM) represents a promising approach for fabricating metallic components at room temperature. However, challenges such as low material deposition rates (MDR), geometric complexity, and slow processing speeds hinder its broader adoption. This study examines the impact of electrolyte temperature on copper monolayers deposited by the Jet Electrodeposition (Jet ECD) technique. A copper sulfate and potassium chloride electrolyte was applied at five distinct temperatures (17 °C, 21 °C, 25 °C, 29 °C, and 33 °C). The experiments were conducted using a CNC hybrid multifunction machine tool, focusing on the ECAM module with Jet ECD. Morphological analysis, 3D profilometry, MDR, and surface roughness (Ra) were evaluated using Scanning Electron Microscopy (SEM) and laser interferometry. The results revealed columnar grains with an average length of 2.477 ± 0.493 µm in the monolayers deposited at 33 °C. The height of the deposited monolayers, measured by 3D profilometry, was consistent across all tested temperatures, remaining within the 30–40 µm range. While no statistically significant change in the MDR was observed due to high experimental variability, the mean values indicated a clear trend, with the MDR at 33 °C (3.5 × 10–5 ± 1.4 × 10–5 mg min−1), approximately double that at 17 °C. The temperature increases also led to a 52% rise in Ra values compared to the lowest recorded roughness, which was 1.12 ± 0.09 µm. In conclusion, electrolyte temperature is a critical parameter in Jet ECD that presents a fundamental trade-off. While higher temperatures promote a trend of increased MDR and columnar grain growth, they do so at the significant cost of higher surface roughness.