Yes, flying under Special VFR (SVFR) absolutely requires an explicit ATC clearance. Special VFR is a set of rules that allows a pilot to operate an aircraft within the lateral boundaries of controlled airspace (usually Class B, C, D, or E surface areas) when the weather conditions are below the standard "Visual Flight Rules" (VFR) minima—which typically require a 1,000-foot ceiling and 3 miles of visibility. With an SVFR clearance, a pilot can operate as long as they stay "clear of clouds" and have at least 1 statute mile of flight visibility. Because the pilot is flying in "marginal" weather where they cannot guarantee separation from other aircraft visually, ATC takes on the responsibility of providing separation between the SVFR aircraft and all IFR (Instrument Flight Rules) traffic. Pilots must specifically request "Special VFR" from the tower or approach control; ATC cannot offer it legally without the pilot asking. At night, SVFR is even more restricted, requiring the pilot to be instrument-rated and the aircraft to be IFR-equipped, as the risk of losing situational awareness in low visibility and darkness is significantly higher.