Several districts in Punjab and Haryana reported air quality indices in the "severe" and "very poor" categories on Wednesday even though the number of stubble-burning incidents dropped in the two agrarian states over the past few days.

Haryana's Hisar and Bhiwani reported the worst air quality in the two states as their AQIs stood at 470 each (severe category), as per the data provided by the Central Pollution Control Board (CPCB).

Among other Haryana districts, Faridabad (AQI 449), Gurugram (446), Jind (445), Fatehabad (430), Sirsa (415), Rohtak (412) and Panipat (408) also recorded their air quality in the "severe" category.

Air quality in other districts such as Kaithal (AQI 313), Karnal (AQI 316), Kurukshetra (AQI 321) was in the "very poor" bracket, as per the CPCB data.

The neighbouring Punjab witnessed air quality in "very poor" and "poor" categories. Amritsar''s AQI was 362, followed by Bathinda (333), Patiala (285) and Jalandhar (276), the CPCB data said.

AQI in the Union Territory of Chandigarh, the joint capital of the two states, was recorded at 242 which is considered as "poor".

An AQI between 0-50 is considered "good", 51-100 "satisfactory", 101-200 "moderate", 201-300 "poor", 301-400 "very poor", and 401-500 "severe". Above 500 is "severe-plus or emergency" category.

Chandigarh meteorological department Director Surinder Paul said that because of the development of high pressure area in the region and absence of vertical movement of air, winds have become static, causing hazy weather condition.

"This weather condition is likely to improve after November 15," he further said.

Meanwhile, the number of incidents of farm fire, considered a major reason for the pollution in the state and neighbouring areas including New Delhi, dropped significantly in Punjab and Haryana.

On November 11 and 12, 794 and 529 incidents of farm fires were reported in Punjab, with Sangrur recording maximum cases, officials said, adding that more than 48,000 incidents of stubble-burning had been reported so far in the state.

An official of the Haryana Pollution Control Board said that some incidents of stubble-burning were reported on Wednesday. However, the exact data was still being tabulated, he said.

Haryana reported a total of 6,099 incidents of farm fires in this season so far, he further said.