Forecasters are predicting near-record highs in the low 100s, with temperatures feeling like 105 to 110 degrees Thursday in the region.
The soaring temperatures have placed Lake and Porter counties under a heat advisory from noon to 8 p.m. Thursday.
The region will see little relief from the heat for the rest of the week, with temperatures staying in the 90s through Sunday.
A jet stream north of the region is causing the heat wave by allowing warm, tropical air into the area, said National Weather Service meteorologist Ben Deubelbeiss.
“That's putting us under this big dome of high pressure that acts like a pressure cooker,” Deubelbeiss said.
Staying safe in the hot weather
Drinking enough fluids and staying out of the sun is key to preventing heat-related illness, Franciscan St. Margaret Heath emergency department physician Dr. Cathleen McGovern said.
“If you have to be out (today) in the heat, get out early in the day or after the sun goes down,” McGovern said. “Try to minimize activity. The best thing is not to exert yourself too much.”
Wearing loose clothing, made of cotton or a breathable fabric, also is advised.
Workers should drink 5 to 7 ounces of fluid every 15 to 20 minutes and take regular rest breaks in shaded areas, according to recommendations released by the Indiana Department of Labor. The state also asks residents to check on neighbors who are elderly or disabled.
Heat, drought conditions affect plants, ash borer
The best time to water plants during hot weather is between 2 and 8 a.m., said horticulturist and Lake County Purdue Extension educator Nikky Witkowski.
Watering during the hottest times of the day is not ideal because most of the water will evaporate before it hits the ground, Witkowski said.
Drought conditions in Northwest Indiana actually are speeding up emerald ash borer’s destruction of ash trees along the Little Calumet River watershed, including in neighborhoods around Hart Ditch, said Cliff Sadof, a professor at Purdue’s West Lafayette campus.
Most treatments homeowners can use on their ash trees need to be applied in the spring before the leaves come out and are sprinkled in a circumference around the roots.
This year, the early arrival of warmer temperatures in March forced all plant life, including trees, to blossom and leaf-out about a month ahead of schedule.
“You can plan for next year, and that will be your last chance to save your ash trees,” Sadof said.