ROCHESTER, N.Y. — The First Alert Weather team is tracking a heat wave this week, with highs through Thursday expected to exceed 90 degrees.

A City of Rochester cool sweep goes into effect on Tuesday. Heat indexes could exceed 100 degrees this week, so limit time in the heat and watch out for any heat-related illnesses. You can see the latest forecast here. Here’s how the city is preparing:

Rochester City School District

The Rochester City School District will have early dismissal for students in Pre-K through 8th grade starting Tuesday for the rest of the week. You can see the early dismissal times on RCSD’s website here. Students will get lunch before they’re dismissed.

High school will remain in session this week and finals and Regents exams will go on as scheduled. Staff will get more instructions on Monday. All after-school activities are canceled.

Fans will be available at school for students and staff. The district in encouraging students to dress in light, breathable clothing and to bring water bottles. All facilities will be closed on Wednesday in observance of Juneteenth.

R-Centers, libraries, and spray parks

The city has a cool sweep planned for Tuesday through Friday. During that time, R-Centers and some library branches will have extended hours to people have access to air-conditioned spaces. The city will also open its spray parks.

The Arnett, Lincoln, and Winton branch libraries will offer extended hours until 9 p.m. this week except for Wednesday, when all libraries will close for Juneteenth. You can see the hours and locations for other libraries here.

These R-Centers will be open from 9 a.m. to 9 p.m. on Tuesday through Friday and 2 to 9 p.m. on Monday. Any students will be served lunches and snacks on Tuesday through Friday and dinner on Monday. Here are the locations:

• Adams, 85 Adams St.
• Avenue D, 200 Avenue D
• Carter, 500 Carter St.
• Frederick Douglass, 999 South Ave.
• Edgerton, 41 Backus St.
• Willie W. Lightfoot, 271 Flint St.
• David F. Gantt, 700 North St.
• Trenton and Pamela Jackson, 485 N. Clinton Ave.
• Thomas P. Ryan, 530 Webster Ave.

These spray parks will be open from 9 a.m. to 9 p.m. on Tuesday through Friday, in addition to 10 a.m. to 9 p.m. on Monday:

• Carter Street R-Center, 500 Carter St.
• Edgerton R-Center, 41 Backus St.
• David F. Gantt R-Center, 700 North St.
• Thomas P. Ryan R-Center, 530 Webster Ave.
• Roxie Ann Sinkler R-Center, 75 Grover St.
• Tyshaun Cauldwell R-Center for Hope, 524 Campbell St.
• Humboldt R-Center, 1045 Atlantic Ave.

These spray parks will be open from 10 a.m. to 8 p.m. on Monday through Friday:

• Dr. Martin Luther King Jr. Memorial Park, 353 Court St. (at the play area)
• Fourth and Peck Playground, Corner of Fourth and Peck Streets
• Troup Street Park, Troup Street and Van Auker Street (between Reynolds Street and Ford Street)

How to prepare for the heat

The American Red Cross says extreme heat kills more people than any other weather event. The Red Cross recommends drinking water throughout the day and avoiding any sugary, caffeinated, or alcoholic drinks which can contribute to being dehydrated. The Red Cross also recommends wearing breathable, loose clothing and having a support team check on your health.

There are three common heat-related illnesses to watch out for. For heat cramps, symptoms include heavy sweating and muscle cramps. For heat exhaustion, symptoms include nausea or vomiting, dizziness, and a fast, weak pulse. For heat stroke, symptoms include confusion and passing out, high body temperature, and red, dry, or damp skin.

If someone is believed to have heat stroke, call 911, move them into a cool place, and don’t give them anything to drink. Instead, cool them using wet cloths, misting, fanning, or a cool bath.

The ASPCA has advice on keeping pets safe in extreme heat. Limit pets’ time outdoors, make sure they have access to water, and never leave them alone in a parked car.

The ASPCA says symptoms of heat-related illness in pets include excessive panting or difficulty breathing, increased heart and respiratory rate, drooling, or mild weakness. Symptoms can also include seizures, bloody diarrhea, and vomiting. Pets with flat faces, like pugs and Persian cats, are more susceptible to heat stroke since they cannot pant as effectively.