ST. LOUIS -- Missouri is bracing for a potentially dangerous round of summer heat.

The National Weather Service has issued an excessive heat warning or watch for much of the state. In St. Louis, the high temperature is expected to reach 100 degrees today through Saturday. High humidity will make it feel even worse.

Kansas City also is expected to top 100 degrees later this week. Accuweather forecasts a high of 97 degrees Thursday in Cape Girardeau.

Friends and relatives are encouraged to check on the elderly. Those without air-conditioning are encouraged to go someplace that has it.

Authorities also warn pets and children should not be left unattended in cars, even briefly.

The hot spell is expected to break next week, when the forecast generally calls for highs in the low 90s.