The Health Ministry issued a warning Tuesday to the population at large, and to the elderly in particular, regarding the weather forecast for the week. A heat wave is expected to hit Wednesday and to continue through Saturday. Saturday will be the Yom Kippur holiday, when many Jews will not eat or drink, in a fulfillment of the Biblical command to fast on the holiday. The heat wave is expected to hit its peak on Friday with temperatures of approximately 40 degrees (104 Fahrenheit) in low-lying regions, 36 degrees (96.8 Fahrenheit) in much of central Israel, and 34 degrees (93.2 Fahrenheit) in hilly regions. The Health Ministry has issued a warning calling to stay out of the heat as much as possible, to drink plenty of water, and to avoid unnecessary physical exertion. The elderly and those with chronic illnesses should take particular care, ministry staff noted.