Heat in Willacy, Texas

The combination of hot temperatures near of just above 100 degrees and high humidity, a remnant of rainfall associated with tropical moisture as Tropical Storm Arthur began to form, created heat index values estimated to be between 111 and 114, with a peak of 115, in inland Willacy County. Observed data from Valley International Airport (Harlingen, about 8 miles south of the county line) and Brooks County Airport (near Falfurrias) were used as proxy data for this area.

As developing Tropical Storm Arthur moved along the middle Texas coast (June 17) and as a degenerated low pressure system along the Louisiana Coast (June 18), very hot air descended on the southern tip of Texas, with record extreme heat index, or feels-like, temperatures for the entire region on the 18th. The high heat index values held on into June 19th, before unsettled weather brought slightly lower temperatures and pockets of rain by the 20th, which ended the short but brutal window of extreme heat.