ITHACA, NY (607NewsNow) – High heat in the Southern Tier.

The National Weather Service has issued a heat advisory in multiple counties, including Tompkins, Cortland, and Tioga, for today, June 30.

Heat index values up to 97 degrees are possible and are expected to increase as the week progresses. Today’s advisory runs from noon until 8 p.m.

Beginning July 1 at 11 a.m., the region will be under an extreme heat watch. Forecasters warn “feels-like” temperatures could reach as high as 105.

The public is advised to drink plenty of fluids, stay in air-conditioned rooms, if possible, avoid the sun, and check up on relatives and neighbors. Do not leave children or pets in unattended vehicles, as car interiors “will reach lethal temperatures in a matter of minutes.”