Extreme Cold/Wind Chill — Willacy, Texas

2024-01-15 to 2024-01-16 · Willacy, Texas

Event narrative

A Minimum Wind Chill value of 11F and 14F degrees was recorded in Harlingen at 5:30 AM and 5:00 AM, respectively. The duration of temperatures within the wind chill criteria (below 20 degrees F) was anywhere from about 8-11.5 hours, by proxy, in inland Willacy County at around the same time. Similar proxy observations and timing was observed in Kenedy County, north of Willacy County.

Wider weather episode

An Arctic cold front ushered in the coldest air mass of the season to Deep South Texas and the Rio Grande Valley with widespread sub-freezing temperatures January 15-17. Subfreezing temperatures arrived during the morning of the 15th as the first surge of cold air arrived. Hard freezes impacted the northern ranchlands for 4 or more hours, with freezing temperatures (28 to 32 degrees) generally from 2 to 7 hours across many inland Valley locations.

The primary surge of arctic air arrived late on the 15th and continued through the late morning of the 16th, as strong high pressure moved into south Texas. Hard freezes occurred in all but locations along the coast. Duration of hard freezes generally lasted from 1 to 4 hours across the Valley, but 5 to 10 hours across the northern ranchlands. Subfreezing temperatures (32 or lower) lasted from 8 to 12 hours in the Valley, but 12 to more than 24 hours (continuing over from January 15) across the northern ranchlands.

Between the pre-dawn hours and mid morning of the 16th, the combination of cold temperatures and gusty northwest winds (15 to 25 mph and gusty) pushed wind chill (apparent) temperatures generally between 10 and 20 degrees across the region for several hours. Wind Chill Warning criteria, sufficient for the Extreme Cold/Wind Chill category, is 20 degrees or lower in Cameron, Willacy, Hidalgo, and Starr (including coastal/island locations), and 15 degrees or lower in Zapata, Jim Hogg, Brooks, and Kenedy County - located north of the region known as the Rio Grande Valley.

Mainly clear skies underneath the core of high pressure late on the 16th into the pre-dawn hours of the 17th allowed temperatures to fall into the 20s to lower 30s in most areas, with one exception being portions of the lower Valley where cloud cover arrived overnight kept temperatures nearly steady. Long-duration hard freezes, between 5 and 10 hours, occurred from the ranchlands to locations north of Interstate Highway 2, with freezing temperatures lasting between 8 and 15 hours for all but the immediate coast and in eastern Cameron County.

Minor damage occurred to crops, with dollar values to be determined as of this writing. Most built infrastructure saw no significant damage, according to reports from local Emergency Management officials. Isolated to scattered power outages were reported across the Rio Grande Valley, mainly on the 16th, but there were no reports of power grid damage due to the freeze.

Source: NOAA Storm Events Database, event_id 1160907. Narrative written by the NWS forecast office that issued the report.