Gurugram, Dec. 17 -- Visibility and air quality index (AQI) showed marginal improvement in Gurugram on Tuesday, though dense smog continued to persist across major stretches of the city, including Golf Course Road, areas near Cyber City and the Delhi-Jaipur-Gurugram (NH 48) expressway during late night and early morning hours, district administration said. According to the India Meteorological Department (IMD), visibility improved from about 800 metres at 8.30am to nearly 7,000 metres by the evening. However, IMD officials said that pollutant dispersal remained poor as wind speeds weakened over the course of the day. Winds blowing at around 8 kilometres per hour to west in the morning slowed significantly by evening, adversely impacting air quality, they added. As per the Central Pollution Control Board (CPCB) bulletin issued at 4pm, Gurugram recorded an AQI of 320, placing it in the "very poor" category, with PM2.5 identified as the dominant pollutant. By 8pm, the district's AQI dropped by 10 points. Among the four air quality monitoring stations operational on Tuesday, readings at Vikas Sadan (AQI 338) and Teri Gram (AQI 324) at 7.30pm continued to remain in the "very poor" category, unchanged since the bulletin issued on Monday. CPCB data showed a marginal improvement at two other stations. AQI levels at Sector 51 improved from 400 on Monday to 312 on Tuesday, while the NISE Gwal Pahari station recorded a drop from 313 to 302, according to data available on the CPCB data. Meanwhile, a major fire broke out at a plastic waste processing site near a crusher zone at Bar Gujjar village in the Manesar Industrial Area at around 7.45am. "Six to seven fire tenders were deployed to calm the flames spreading in an open space of around 1.5 acres. The fire was completely taken under control at around 1.30pm," said Lalit Verma, fire officer in Manesar. Investigators said preliminary findings suggested that a suspected mishap during waste processing triggered the fire, which took nearly three hours to be brought under partial control. The IMD forecasts similar dry weather conditions with shallow smog in many areas and isolated smog in some locations across the National Capital Region (NCR) on Wednesday and Thursday. Gurugram recorded a minimum temperature of 9.3degC and a maximum of 22.6degC on Tuesday....