Heat — Willacy, Texas

2024-05-22 · Willacy, Texas

Event narrative

Harlingen Valley International Airport (KHRL) recorded max heat indices between 111-114F for nearly four hours from 130 to 515 PM CDT on May 22, 2024. By proxy, and data from northern Kenedy (1 hour of 111 to 112 heat index during this window), it can be inferred that inland Willacy County had similar heat index values for a similar period of time.

Wider weather episode

A strong upper-level subtropical ridge/heat dome centered over central and southern Mexico strengthened and shifted northward towards the Rio Grande Valley and Deep South Texas ranchlands the week prior to Memorial Day. The strong ridge aided lower level temperatures at around five thousand feet to soar to between 78 and 86F, which translated to surface temperatures rising into the upper 90s to mid 100s on most days between May 21-25. With dewpoint temperatures well into the 70s to around 80, apparent temperatures (feels like temperatures) ranged anywhere between 111-116F across parts of Deep South Texas and the Rio Grande Valley with a few locales reaching higher than this. The hottest apparent temperatures were located along and east of IH-69C from Hidalgo and Brooks County to Cameron, Willacy, and Kenedy County - but all of Deep South Texas observed at least dangerous heat levels by local definition (111F or higher for at least two hours) on most days.

Actual temperatures during the period were even hotter than the peak of the summer heat (late July through mid August) for most areas. The month would shatter all-time temperature records by 1 to more than 3 degrees.

Source: NOAA Storm Events Database, event_id 1184135. Narrative written by the NWS forecast office that issued the report.