Serious summer heat is on the way as temperatures are expected to hit the 90s for most of the week with the hottest day coming Friday at 95 degrees in Baton Rouge and 93 in New Orleans and Lafayette.

The increasing heat is thanks to a high pressure ridge building over the plains states this week causing temperatures to rise and chances of rain to fall. This weather combination will help temperatures to continue to rise to the low to mid 90s which is just slightly more than the normal high temperature of around 90 degrees in Baton Rouge and New Orleans this time of year, said Freddie Zeigler, meteorologist at the National Weather Service in Slidell.

The heat index will also continue to go up with the possibility of reaching 105 degrees or more on Friday and Saturday.

At that heat index level, people need to take precautions during outdoor activities against sunstroke, muscle cramps or heat exhaustion. People should drink more nonalcoholic fluids, take frequent breaks in activities and rest in shady areas when possible, according to the Centers for Disease Control and Prevention.

Usually, the National Weather Service will issue a heat advisory when heat indexes get to 105 or 106 and caution extreme danger when the heat index gets to 120 to 125 degrees. Heat indexes in the 120s is rare, Zeigler said, and in south Louisiana has only occurred maybe once every three years and then only for a couple hours at a time.

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