Economy Delhi records longest cold day spell since 1997, air quality remains 'very poor' Updated : December 25, 2019 01:15 PM IST Not just Delhi, but neighbouring Noida, Ghaziabad, Faridabad and Gurugram were also under the grip of severe cold wave. SAFAR suggests a slight improvement in wind speed, and a marginal improvement in AQI is forecast for Thursday but within the very poor category. Subscribe to Moneycontrol PRO at just Rs.33/- per month for the first year. Use code SUPERPRO. Limited period offer. Available on Web and Android.