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The influence of temperature and rainfall on nutrient levels, heavy metals, and etiologic agents in sludge samples collected at the Sewage Treatment Station of Juiz de Fora, Minas Gerais, Brazil, was verified over 24 months. The results showed high levels of nitrogen (4.7-5.2%), phosphorus (1.4-2.2%), potassium (0.076-0.106%), magnesium (0.113-0.386%), iron 5.03%) and zinc (38.2-6902.1 mg Kg-1). For most of the investigated samples, the concentration of zinc was above the maximum allowed value (2,800 mg Kg-1). The concentrations of arsenic, cadmium, chrome, copper, and lead were below the maximum values allowed by the legislation. Parasitological analyzes identified thermotolerant coliforms (0.49-160 NMP g-1) and helminth eggs (1 egg), however, in amounts less than allowed by legislation. These results are indicative of the efficiency of the sewage treatment process. The results showed a significant influence of the meteorological parameters on the concentrations of nitrogen, copper, lead, zinc and pathogens in the sludge. The results also showed a strong correlation between the concentrations of copper, lead and zinc indicating that the presence of these elements in the sewage sludge has a common origin. The results demonstrated the feasibility of using the investigated matrix as fertilizer when collected in rainy periods when it favors the dilution of the elements present in their soluble forms.