At least 12 people died over 24 hours after heavy rains, thunderstorms and flash floods gripped different provinces of Pakistan as an average 30 to 45 mm precipitation for four hours threw life out of gear in Karachi on Thursday.Authorities declared an emergency in Karachi as heavy rains that started Thursday morning, triggering urban flooding and severe disruption of normal life and traffic in the city.Rescue services, including Edhi Trust and Chippa Welfare, confirmed five deaths due to electrocution and house walls collapsing in different areas.As cold and strong winds swept across Karachi, signboards were uprooted, trees fell and roads in many areas were flooded with water forcing authorities to declare an emergency.Power supply was also disrupted in many areas of the city as soon as the rains started.The Pakistan Meteorology Department (PMD) said the average rain in Karachi varied from 45 mm to 30 mm at different locations by Thursday afternoon.According to the official PMD data, the highest rainfall was recorded in Nazimabad (Paposh Nagar) at 69.6 millimeters, followed by Kemari with 56 mm and Saadi Town with 48 mm from 10 am to 2 pm.The met office said the average rain in Karachi varied from 30 mm to 45 mm in different locations.PMD metrologist Anjum Nazir in Karachi said that two more heavy spells of rain are likely to hit Karachi later Thursday evening and late night.In Balochistan, the Pakistan Disaster Management Cell reported seven deaths in various parts of the province including Turbat, Kohlo, Jaffarabad, Loralai, Harnai and Quetta due to heavy rains since Wednesday.Around 100 houses were damaged and 50 livestocks killed in the heavy rains, which also caused flash floods and flooding in Killa Abdullah, about 100-odd kilometres northwest of Quetta, the province’s capital.A passenger bus with 15 persons on board was swept away in the Killa Abdullah area, officials said. Rescue teams are trying to locate the bus to rescue the passengers.The PMD in its forecast also said that a Westerly wave is likely to affect upper parts of the country from Thursday night and is expected to persist till April 8 with intermittent rain.Under the influence of this weather system, widespread rain / thunderstorm and gust, accompanied by moderate to heavy rainfall and snowfall over hill tops, is expected in several areas of Khyber Pakhtunkhwa province, the PMD said.Several districts in Himalayan mountain areas too would be affected and the persistent precipitation, coupled with the snowmelt in high-altitude catchments, and intense runoff generation may significantly aggravate hydro meteorological hazards in vulnerable valleys with a probability of Glacial Lake Outburst Flood (GLOF) in vulnerable glaciated basins and downstream settlements, the PMD warned.Heavy rainfall over steep slopes may trigger landslides, mudslides, debris flow and rockfall in mountainous districts, it said adding, sudden rise in discharge is expected in Chitral River, Swat River and associated tributaries.