LUCKNOW, June 13 -- As sweltering heat continues across Uttar Pradesh, Lucknow recorded its hottest day of the season so far at 44 degrees Celsius on Thursday, said India meteorological department's Lucknow office. Orai and Banda were the hottest cities in the state with 44.8 degrees Celsius each followed by Jhansi with 44.7 degrees. Agra and Kanpur recorded the temperature of 44.6 degrees Celsius while Varanasi and Prayagraj also sweltered at 44 degrees. A heat wave alert has been issued for Ghaziabad, Gautam Buddh Nagar, Aligarh, Mathura, Hathras, Agra, Jhansi, Firozabad, Etawah, Auraiya and Jalaun districts. A weatherman said the mercury levels are set to stay higher than normal on Friday and record a gradual decrease from June 14. "Following no major changes in temperatures during the next 24 hours, higher than normal temperatures are likely to prevail across the state on Friday leading to isolated heat wave and warm night conditions," said senior scientist at Lucknow IMD Atul Kumar Singh. "However, the weather conditions are likely to ease after June 14 in western UP as a result of an increase in rainfall activities from eastern UP and gradually moving towards western UP. There will be a respite from scorching heat from June 15 onwards in most parts of the state," he added. Elaborating on the phenomenon, he said this was because of revival of stagnant monsoon in southern peninsular India expected from Friday onwards which will activate the Bay of Bengal branch with formation of a system in coming days. On Thursday, heat waves were experienced in Ghaziabad, Gautam Buddh Nagar, Mathura, Agra, Jhansi and adjoining regions. Heat waves are likely at some places on Friday and thunderstorms accompanied by lightning and gusty winds (30-40 kmph) are likely at isolated places in west UP. Thunderstorms accompanied by lightning and gusty winds (40-50 kmph) are likely at isolated places and heat wave is likely at some places during the day in east UP....