After the fog lifts by mid morning, expect a warm, humid and mostly cloudy Friday in the Rio Grande Valley, according to the National Weather Service in Brownsville.
Temperatures will warm into the mid to upper 80s for much of the region, with lower 90s possible west of Highway 281.
Both McAllen and Rio Grande City will be 90 degrees. Brownsville will check in at 84, and South Padre Island will be 73.
Looking ahead, warm temperatures are expected through the middle of next week with highs in the 80s and 90s. There is a 30 percent chance for thunderstorms Saturday and Sunday.
A very weak cold front is still forecast to push through the Valley on Monday morning but is not expected to cool temperatures much. It will, however, dry the air slightly for Monday and Tuesday.
By Wednesday, winds increase and turn back out of the southeast, increasing the humidity and temperatures. On Wednesday, some areas may be in the upper 90s.