According to the National Weather Forecasting Centre of the India Meteorological Department (IMD):
Salient features of month of Feb 2021
(a) Western Disturbances (WDs):
Six WDs and four induced cyclonic circulations affected Northwest India during Feb 2021. Among these, two WDs caused scattered to fairly widespread rainfall/snowfall activity over Western Himalayan Region and isolated to scattered rainfall/thunderstorm activity over adjoining plains of Northwest India. Isolated hailstorm activity also occurred over Western Himalayan Region during the passage of these two systems.
(b) Wet spell over central, peninsular and adjoining eastern India:
A Wet spell with isolated Hail storm occurred over Central, eastern India, Maharashtra during 16-19 Feb and then over Peninsular India during 19-22 Feb 2021, under the influence of interaction of mid-latitude westerly winds in middle and upper troposphere and lower level easterly winds.
(c) Monthly Rainfall Scenario over the country (01 to 28 Feb2021):
Rainfall over the country as a whole for the month of Feb,2021 was 7.6 mm, which was -68% less than its Long Period Average (LPA) of 23.5 mm as shown in Table 1. Fig. 1 shows Meteorological subdivision-wise rainfall during Jan 2021. During this month, 9 sub-divisions received large excess, 2 normal while remaining 23 received deficient or large deficient rainfall and 2 (Saurashtra & Kutch and west Rajasthan) received no rain.
(d) Occurrence of Unusual prolonged spells of very dense fog over Punjab and Haryana during 10-22 Feb 2021:
As per surface observations and satellite images from INSAT 3D, extensive dense to very dense fog were reported persistently from late night till late morning almost every day during the period of 10-22 Feb 2021 over many areas of Punjab and Haryana. Fig 2 shows this dense fog coverage as captured by INSAT 3D at 0845 hours IST of each date for the period of 11-21 Feb. 2021. Due to such dense fog, visibility was reduced to < 200m during night to morning in most dates over these areas. In Amritsar, for 1-28 Feb. 2021, dense fog in the month in total was observed for 15 days with 168 hours. This dense fog frequently extended eastwards over parts of Delhi and west Uttar Pradesh and also southwards, to northwestern parts of Rajasthan (refer Fig 2) for around 7-10 days during the period. It was observed for 7 days with a total of 28 hours at IGI Airport, Delhi.