Expect a warm and mostly cloudy day with highs in the 70s and low 80s across the Rio Grande Valley, according to the National Weather Service in Brownsville.
Highs in Brownsville may reach 81. McAllen could see a high of 80 degrees.
Temperatures will drop Wednesday as a weak cold front moves into the region. Expect highs to range from 66 to 72 with lows in the upper 50s to low 60s.