Chandigarh, April 20 -- The India Meteorological Department has issued a three-day yellow alert starting Tuesday, warning of heatwave conditions and warm nights in isolated parts of the city. In response, health departments across the tricity have released advisories, urging residents to take precautions against the expected rise in temperatures. According to IMD criteria, a heatwave is declared when the maximum temperature departs from normal by 4.5degC to 6.4degC, or when the actual maximum temperature exceeds 45degC. A severe heatwave is declared when temperatures rise above 47degC. The maximum temperature is expected to climb to 41degC by Friday, while the minimum may reach 23degC. With rising heat, both the UT and Mohali district health departments have issued public health advisories, asking residents to be prepared and aware. On Sunday, the city recorded a maximum temperature of 39.3degC, slightly lower than Saturday's 40degC, but still about 4degC above normal. The minimum temperature rose to 20.8degC, marking an increase of 1.4degC over the previous 24 hours. Health officials have advised people to avoid direct sun exposure and stay indoors as much as possible, as extreme heat can lead to moderate to severe health complications, especially among vulnerable groups. UT director health services, Dr Suman, stated that emergency services are fully prepared to handle heat-related illnesses. Similarly, Mohali civil surgeon Dr Sangeeta Jain, said the district has made adequate arrangements, including functional heat stroke units in government hospitals, reserved beds for affected patients, and sufficient stocks of essential medicines such as ORS at all health facilities. Senior medical officers have been directed to remain on high alert and ensure round-the-clockreadiness....