An excessive heat warning is in effect across much of southeast Louisiana Tuesday, where dangerously high temperatures, humidity and heat index values of up to 118 degrees are expected through the day.
New Orleans, Baton Rouge and Lafayette are all expected to face oppressive heat through Tuesday evening, according to the National Weather Service of New Orleans. Daytime highs of around 97 degrees and "feels-like" temperatures well into the triple digits are expected across much of the region.
More high temperatures are expected across the region through the week, although National Weather Service forecasters said looming showers and thunderstorms should tamp temperatures down some on Wednesday.
Still, forecasters said heat indices could reach up to 108 degrees in areas that manage to stay dry. And as rain chances taper off after Wednesday, more intense heat is expected on the Fourth of July and through the end of the week.
Tuesday's heat warning is in effect through 7 p.m. in most of southeast Louisiana, excluding only some coastal areas, and portions of southwest Mississippi.
Little relief is expected overnight, forecasters said, with heat indices of up to 90 degrees forecast Tuesday night and early Wednesday morning.
"The cumulative effect of prolonged high heat indices each of the last few days accompanied by little relief overnight will heighten the risk for heat-related illness in populations more susceptible," forecasters said in a 6:30 a.m. heat update.
Heat illness can come on suddenly in such high temperatures, according to the National Weather Service. Drink plenty of fluids, stay in an air-conditioned room, stay out of the sun, and check up on relatives and neighbors, particularly those without AC or who work outside.