LUCKNOW, June 16 -- As the state capital experienced a brief spell of sporadic pre-monsoon showers in the early hours of Sunday, the Lucknow meteorological office is hopeful that the southwest monsoon may enter the eastern parts of the state anytime between Tuesday and Friday. Even the normal date for monsoon onset in Uttar Pradesh, which is through Gorakhpur, is June 18, weathermen said. The sporadic pre-monsoon rainfall activities are signs that conditions are favourable for the southwest monsoon's onset between June 17 and 20. There is a possibility of a gradual increase in rainfall activities, which will be accompanied by thunderstorms and lightning, from Wednesday. "Temperatures may plummet by 3 to 5 degrees over the next three to four days, resulting in a significant decrease in the heat index. A complete relief from the humid conditions is expected after June 16," said Atul Kumar Singh, a senior scientist at the Lucknow Met. Meanwhile, at 43.2 degrees Celsius, Varanasi (BHU) was the hottest IMD centre, not just in UP but across the country. At Varanasi (airport), mercury rose to a high of 41.9 degrees, followed by 41.5 in Ghazipur. The weathermen said thunderstorm, accompanied by lightning/gusty winds (speed 40-50 kmph), were very likely at isolated places in West UP and in a few places in East UP. In Lucknow, the maximum and minimum temperatures were recorded at 39.9 and 26.2 degrees, respectively. On Monday, it may experience partly cloudy skies with a spell or two of rain/thundershowers. HTC...