The present disclosure relates to methods and devices for reducing moisture, dust, particulate matter, and/or other contaminates entering a sensor. A sensor assembly may include a housing with an inlet flow port and an outlet flow port. The housing may define a fluid channel extending between the inlet flow port and the outlet flow port, with a sensor positioned in the housing and exposed to the fluid channel. The sensor may be configured to sense a measure related to the flow rate of a fluid flowing through the fluid channel. A hydrophobic filter may be situated in the fluid channel, sometimes upstream of the sensor. When so configured, and during operation of the sensor assembly, a fluid may pass through the inlet flow port, through the hydrophobic filter, across the sensor, and through the outlet flow port.