New Delhi, Jan. 12 -- The Capital shivered through Sunday as isolated pockets recorded "cold wave" conditions with the minimum temperature plummeting to as low as 2.9 degrees Celsius (degC) at the Aya Nagar weather station. Safdarjung, representative of Delhi's weather, recorded a minimum of 4.8degC - three notches below normal and up from 4.2degC on Saturday. Other stations in the city were colder, with 3degC logged at Palam and 3.7degC at Ridge. According to the India Meteorological Department (IMD), Sunday was the coldest January morning in Palam in the last 13 years, since the station recorded 2.6degC on January 7, 2013. As per forecast by the IMD, "cold wave" will continue in the national Capital till Wednesday. The Met department has issued an orange alert for "cold wave" in the city for Monday and Tuesday and yellow alert for Wednesday. "It is expected at many places on Monday and Tuesday and in isolated pockets on Wednesday," an IMD official said. "Cold wave conditions were witnessed over Delhi as Palam, Ridge and Ayanagar reported minimum temperatures less than 4.1degC. No respite from the chills is expected in the coming days," IMD scientist Krishna Mishra said. Delhi's air quality on Sunday improved slightly from "very poor" zone to the higher end of "poor". As the wind speeds picked up on Sunday, the 24-hour average air quality index (AQI) stood at 291 (poor) at 4pm, as against 346 (very poor) at the same time on Saturday, according to the Central Pollution Control Board (CPCB). Forecasts by Centre's Air Quality Early Warning System (EWS) for Delhi shows that a deterioration is again expected on Monday. "The air quality is likely to be in the 'very poor' category from January 12 till January 14," the EWS mentioned in its daily bulletin on Sunday....