Islamabad, June 23 : Pakistan Meteorological Department (PMD) has predicted pre-monsoon rains with dust thunderstorms in upper and central parts of the South Asian country alongside occasional gaps from Sunday to Friday. The prevailing heat wave conditions in most parts of Pakistan which started this week are likely to subside from Sunday, the PMD said on Thursday in a statement. The department added that moist currents from the Arabian Sea are penetrating in upper and central parts of the country while a westerly wave is likely to enter in upper parts of Pakistan on June 25, Xinhua news agency reported. During the prevailing heat wave, the PMD forecasted daytime temperatures to likely remain 4-6 degrees Celsius above normal in upper and central parts and 2-4 degrees Celsius above normal in southern and southwestern parts of Pakistan. In the wake of the heat wave, the weather agency advised the general public to avoid unnecessary exposure to direct sunlight. Additionally, the PMD predicted an increase in power and water supply demand due to a rise in temperatures, for which it urged the farmers to manage the watering of their crops accordingly. /IANS