Shallow mixed-phase clouds (MPCs) occur extensively in the Arctic, and are known to play a key role for the energy budget. While their characteristic structure is nowadays well understood, the significance of different precipitation-formation processes, such as aggregation and riming, is still unclear. Using a 3-year dataset of vertically-pointing W-band cloud radar and K-band Micro Rain Radar (MRR) observations from Ny-Ålesund, Svalbard, we statistically assess the relevance of aggregation in Arctic low-level MPCs. Combining radar observations with thermodynamic profiling, we find that larger snowflakes (mass median diameter above 1 mm) are predominantly produced in shallow MPCs whose mixed-phase layer is at temperatures between -15 and -10°C. This coincides with the temperature regime known for favoring aggregation due to growth and subsequent mechanical entanglement of dendritic crystals. Doppler velocity information confirms that these signatures are likely due to enhanced ice particle growth by aggregation. Signatures indicative of enhanced aggregation are however not distributed uniformly across the cloud deck, and only observed in limited regions, suggesting a link with dynamical effects. Low Doppler velocity values further indicate that significant riming of large particles is unlikely at temperatures below -5°C. Surprisingly, we find no evidence of enhanced aggregation at temperatures above -5°C, as is typically observed in deeper cloud systems. Possible reasons are discussed, likely connected to the ice habits that form above -10°C, increased riming, and lack of already aggregated particles precipitating from higher altitudes.