Excessive Heat — Willacy, Texas

2024-05-26 · Willacy, Texas

Event narrative

Harlingen Valley International Airport (KHRL) recorded max heat indices between 113-119F for 6 hours, from 11:52 AM-5:52 PM CDT on May 26, 2024. Heat indices reached Excessive Heat Warning criteria with values between 116-119F for 4 hours, from 12:52-4:52 PM CDT. By proxy, Valley International Airport combined with the Texas AgriScience Center location just west of the Willacy/Hidalgo line, which recorded 116-118F heat index values between 420 and 550 PM, are proxy values used to infer heat index values. Dangerous heat (111F or higher) began approximately one to two hours on either side of the excessive heat conditions.

Wider weather episode

A slightly stronger sub-tropical ridge/heat dome centered over central and southern Mexico returned northward towards the Rio Grande Valley and Deep South Texas. At five thousand feet above ground, the temperature soared anywhere from 78 to 90 degrees Fahrenheit, which translated into another short-lived but intense heat wave over the region with surface temperatures rising into the upper 90s to mid 100s from May 26-30. The combination of heat and dewpoint temperatures well into the 70s to around 80, heat indices ranged between a sweltering 111F-126F across parts of Deep South Texas and the Rio Grande Valley. The hottest temperatures were once again located from the mid-lower Rio Grande Valley northward along I-69E and I-69C; several hours with values of 116 or higher - considered Excessive Heat - were noted each day in many parts of the region.

Source: NOAA Storm Events Database, event_id 1183099. Narrative written by the NWS forecast office that issued the report.