Excessive Heat — Central Plaquemines Parish, Louisiana

2025-07-28 · Central Plaquemines Parish, Louisiana

Event narrative

A combination of heat and humidity allowed heat indices to climb into the 113-115 degree range on July 28th, which meet extreme heat conditions.

Wider weather episode

On July 28th, another day of extreme heat gripped southeast Louisiana and coastal Mississippi, with heat indices once again soaring into the 113'115 range. Surface analysis showed a sprawling ridge of high pressure centered over the Gulf and extending northward, suppressing convection and allowing oppressive heat and humidity to build unchecked. At the mid-levels, 500 mb heights climbed to near 594'599 dm across the region, signaling a strong, stagnant ridge overhead. This ridge trapped moisture near the surface while limiting vertical mixing, creating a 'heat dome' effect that magnified dangerous heat stress. With little in the way of frontal passages or organized lift, conditions remained static through the afternoon, prolonging the exposure to extreme heat indices and exacerbating impacts for vulnerable populations.

Source: NOAA Storm Events Database, event_id 1286987. Narrative written by the NWS forecast office that issued the report.