NOIDA/GHAZIABAD, Jan. 3 -- The air quality in Noida, Greater Noida, and Ghaziabad improved significantly on Friday and slipped into the "poor" category from "very poor" due to light drizzle and increased moisture in the region. In view of the improved air, the Commission for Air Quality Management (CAQM) on Friday revoked Stage 3 restrictions under the Graded Response Action Plan (Grap) across Delhi-NCR, officials said. According to the Central Pollution Control Board (CPCB), the air quality index on Friday stood at 229 in Noida, 238 in Greater Noida and 239 in Ghaziabad - all three in the "poor" category - as against 367, 352, and 356, respectively, on Thursday. On Wednesday, AQI was 382 in Noida, 366 in Greater Noida and 312 in Ghaziabad. Weather department officials attributed the temporary improvement in air quality to the season's first winter showers and moisture, which swept across large parts of north India, including Uttar Pradesh, Punjab, Haryana, Rajasthan and Gujarat, beginning on New Year's Eve. While no measurable rainfall was recorded locally, elevated humidity levels helped settle pollutants, they said. The India Meteorological Department (IMD) recorded a minimum temperature of 11.7 degrees Celsius in Gautam Budh Nagar and 11degC in Ghaziabad on Friday. Maximum temperatures were not available at the time of reporting, though the day remained cold and damp under persistent foggy conditions. Forecast showed that maximum temperature is expected to hover around 15degC in Gautam Budh Nagar and 16degC in Ghaziabad, while minimum temperature is likely to remain near 9degC. Relative humidity levels stayed high, ranging between 80% and 90%, creating favourable conditions for fog formation. Mahesh Palawat, vice-president, climate and meteorology, Skymet Weather, said the region is now entering a harsher phase of winter. "The foothills and plains of north India received the first typical winter showers. Weather conditions have now improved and rainfall has ceased," he said. Palawat added that snowfall in the mountains have set the stage for elevated winters across north India. "Frigid winds are expected to descend from the mountain slopes, triggering piercing cold across the plains. Dense fog will add to the misery," Palwat added....