The weather department has predicted fairly widespread rainfall over parts of north-west India on August 22, with the possibility of heavy rainfall at isolated places in Punjab and Haryana, even as seasonal rainfall continues to be deficient and water levels in key reservoirs remain below normal.Over the past 24 hours, the monsoon was active over Punjab and normal over Haryana, with light to moderate rain, along with thunderstorms and gusty winds, occurring at many places in Punjab.Heavy rain was also reported at isolated places in the state, according to a bulletin issued by the India Meteorological Department (IMD) on Friday. In Haryana, light to moderate rain occurred at isolated places.The monsoon is 22 per cent below the long-period average (LPA) in Punjab during August so far, whereas it is 10 per cent above the LPA in Haryana.From August 1 to August 21, Punjab received 85.4 mm of rain against the LPA of 109.7 mm for this period, while Haryana received 116.2 mm against the LPA of 105.4 mm. Seasonal rainfall since June 1 is below the LPA by 28 per cent in Punjab and by 18 per cent in Haryana, according to IMD data.The water levels in reservoirs at three major dams in the region, which are crucial for power generation and irrigation, are also significantly below normal, even though the monsoon season is more than halfway through.The water level recorded at Bhakra Dam on the Sutlej in Himachal Pradesh on the morning of August 21 was 1,629.32 feet against the permissible upper limit of 1,680 feet, while the level at Pong Dam on the Beas in Himachal Pradesh was 1,362.04 feet against the top mark of 1,390 feet.The inflow into the Bhakra reservoir was 48,309 cusecs, while the outflow was 24,112 cusecs on August 21, according to information shared by the Bhakra Beas Management Board. At Pong, the inflow was 39,639 cusecs and the outflow was 15,106 cusecs.The present storage at Bhakra is 53.87 per cent of its full capacity of 6.229 billion cubic metres (BCM). It was 80.09 per cent at this time last year, while the past 10-year average is 70.07 per cent, according to data shared by the Central Water Commission (CWC) on August 20.At Pong, the present storage is 61.94 per cent of its full capacity of 6.157 BCM. It was 85.83 per cent at this time last year, while the past 10-year average is 69.48 per cent. The storage at Thein Dam on the Ravi in Punjab is currently 58.60 per cent of its full capacity of 2.344 BCM.It was 83.58 per cent at this time last year, while the past 10-year average is 66.83 per cent, CWC data showed.A large part of the catchment areas of these dams lies in Himachal Pradesh, where most of the rivers and tributaries feeding their reservoirs originate. Seasonal rainfall in the state has been 8 per cent below the LPA, while August rainfall is 13 per cent below the LPA, according to the IMD.The weather department has predicted fairly widespread to widespread rainfall, with isolated heavy falls likely over the western Himalayan region during the first half of the current week and on some days of the following week.Isolated heavy to very heavy rainfall is also likely over Himachal Pradesh, Uttarakhand and Jammu and Kashmir on several days of the following week.