The season’s hottest stretch of summer weather is about to engulf northern Indiana as it moves slowly across the nation’s midsection. Today’s expected high temperature of 87 appears to be a warm-up act for what’s predicted to arrive Friday and remain through the weekend as humid conditions and high temperatures push into the lower 90s. Heat index values – the “feels like” factor – are expected to creep above the 100 mark in some areas from Thursday through Sunday, the National Weather Service said. As a result, the weather service has issued a hazardous weather outlook. There also is a chance of storms Thursday through Sunday, but overall it is expected to be a mostly dry period. And yet, the weather service cautions that isolated strong to severe storms are possible Thursday and Friday. Thursday’s high is expected to reach 90, and the low will be around 74. Friday’s high will be around 92 and the low will be near 72. Saturday and Sunday’s highs will be around 91, according to the weather service. Other forecasts, though, are predicting higher temperatures. WSBT predicts the high temperature in Warsaw on Friday could reach 95. Nationally, the heat wave extends from Canada to the Gulf of Mexico. The most excessive heat today was expected to remain west of Indiana and begin to move slowly to the east.