After a three-day hiatus, heat wave conditions returned to some parts of Punjab, however, a four-day wet spell predicted over many areas of north-west India from May 28 is expected to bring relief from the sweltering heat as it is likely to lower temperatures by several degrees.Over the past 24 hours, day temperatures in Punjab remained above normal, with the India Meteorological Department (IMD) reporting a heat wave over Bathinda, where the maximum temperature recorded was 45.8 degrees Celsius. Night temperatures in Punjab remained normal.In Haryana, heat waves continued to prevail over Sirsa, Rohtak and Ambala, with day temperatures in the state being appreciably above normal, while night temperatures remained near normal. The maximum temperature recorded in Haryana over the past 24 hours was 46.6 degrees Celsius in Rohtak.According to a bulletin issued by IMD on May 27, light rainfall is likely at a few places in Punjab and Haryana on May 28 and May 31, and fairly widespread rainfall is expected in both states on May 29 and May 30. IMD has predicted that day temperatures may fall by 6-8 degrees Celsius.A fresh western disturbance is likely to affect north-west India from May 28. IMD expects more rain in north-western parts of Punjab and Haryana than other areas in these states during the aforementioned days.Rainfall for the month of May so far has been below the long period average (LPA) by 35 per cent in Punjab and 11 per cent in Haryana, although the seasonal rain from March 1 onwards has been above LPA by four per cent in Punjab and 14 per cent in Haryana, the IMD data revealed.Thunderstorms, lightning and gusty winds with speed reaching 70-80 kmph are expected in these states over the next four days and hailstorm activity is also likely to occur at isolated places on May 28 and May 29.IMD has also forecasted scattered to fairly widespread light to moderate rainfall with thunderstorm, lightning and gusty winds over Jammu and Kashmir and Uttarakhand till May 30 and Himachal Pradesh on May 28 and May 29.Thunder-squalls, with wind speed reaching 100 kmph, are also likely over Punjab, Haryana, Chandigarh, Delhi, Rajasthan, Jammu and Kashmir, Uttarakhand and western Uttar Pradesh on May 28 and May 29.Isolated hailstorm activity is also likely over Himachal Pradesh, Uttarakhand and western Uttar Pradesh on May 28 and May 29, IMD said.