KATHMANDU: Brief rain or thundershowers are likely to occur at some places of the eastern, western and central regions, including the Kathmandu Valley, on Monday, said the Meteorological Forecasting Division. If the Valley receives rain, the thick haze in the sky will be settled. Changing weather pattern has blanketed the sky of the Valley for the past few weeks. Favourable winds also help clear the haze. The average monthly rainfall in March is 34.2 mm in the Valley but it received only 6.2 mm rain so far. Weeks of dry spell, coupled with Asian Brown Cloud, comprising black carbon and ash, sulfates, nitrates and mineral dust, has had an adverse impact on the Valley.