LANCASTER – An extreme heat watch has been issued for our region beginning Sunday morning through Wednesday evening. Dangerously hot conditions with heat index values over 105 are possible. Heat index values and the associated risk of heat-related impacts will be highest on Monday and Tuesday. Folks are urged to prepare for the upcoming heat wave. Check up on relatives and neighbors and provide pets with adequate water and shelter from the sun. Wear lightweight and loose fitting clothing. In addition to the daytime heat, overnight low temperatures will also be very warm and oppressively muggy during the period.