This year's early bout of heat is likely to blame for the early sightings. The National Weather Service has issued warnings for much of Southeast Texas this week, where an unseasonably intense heat wave is developing. Cities like Houston are expected to hit the mid to upper 90s this week, possibly breaking temperature records for May.

The Dallas-Fort Worth area will be unseasonably scalding Wednesday, but other areas of Texas are expected to cook even more. The projected high for the metro area has hovered near 100 degrees all week and Wednesday’s most updated forecast from the National Weather Service’s Fort Worth office has landed on 100 degrees exactly.

The Texas-Mexico border is scorching under a record-setting heat wave, with temperatures soaring past 100 degrees, making it Earth's hottest spot today.

Summer temperatures in Central Texas are predicted to break records this week. You can almost feel the heat coming off these photos.

Record-breaking Texas heat threatens millions as forecasts predict nationwide temperature extremes through summer. Learn the risks and how climate changes

Texas is bracing for a relentless and potentially historic heat wave this week, with dangerously high temperatures expected statewide.