While characterization of urban stormwater runoff as a major transport pathway of pollutants to receiving environments is of the utmost importance, restrictions on access to online sensors and infrequent grab sampling has led to limitations in assessing storm runoff quality in many urban systems. The application of turbidity (TURB) and total suspended solids (TSS) as useful surrogate measures for metals concentration have proved in various catchments, but their predictive capability for highly urbanized catchments especially in arid and semi-arid regions with long dry periods and intense but short-lived precipitation events is missing. In this study, the suitability of TSS and TURB as surrogates for high frequency quantification of total metals concentration in storm events of Tehran City as a highly urbanized catchment is investigated. TSS, TURB and nine metal concentrations were measured in water samples collected from the base flow and eight flood events at the outlet of eastern Tehran catchment from April 2018 till November 2020. Robust relationships found between TSS and metals concentrations through the whole time span of the research, which indicate TSS was a significant explanatory variable for total metals concentration in this highly urbanized catchment. Stable relationships throughout a remarkable temporal resolution are justified by dominance of resuspension of accumulated particles in main channels and tributaries during flood events. Replicable results were reproduced through a laboratory resuspension-sedimentation experiment on collected sediments from the sampling station. Regarding the meaningful correlation between TSS and TURB (R-2 = 0.96) [as a parameter capable of being monitored online in a reasonable cost], online monitoring of metals' load/flux transported during flood events could become possible. Urban catchment-specific relationships, however, should be first determined before initiation of above-mentioned processes.