Humidity from the Gulf of Mexico and hot air from the Desert Southwest willcombine to produce very steamy conditions through the South Central statesTuesday. From central Texas to the Mississippi Valley, the heat index willreach 105 degrees or higher Tuesday afternoon.The heat and humidity will cause thunderstorms to boil up through southeasternTexas. These can cause brief downpours, but destructive winds and tornadoes arenot likely to occur.

Across the Southeast, Tuesday will be very warm with highs in the upper 80s andlower 90s, but the humidity will stay away.

Story by AccuWeather.com Senior Meteorologist John Kocet.