The Antigua and Barbuda Meteorological Service (ABMS) has issued an Excessive Heat Warning, urging residents and visitors to take urgent precautions as dangerously high temperatures continue to scorch the twin-island state.

The alert, which took effect Thursday, remains in force from 8:30 a.m. to 4:30 p.m. each day through Sunday, September 28.

Forecasters warn that the heat index, which measures how hot it feels when humidity is combined with actual air temperature, is expected to climb as high as 43 °C (109 °F).

Winds remain weak, averaging just 18 km/h (11 mph) or less, offering little relief from the oppressive heat. Officials caution that conditions will be most hazardous during the early afternoon hours when temperatures peak.

Medical experts are warning that the heat can trigger illnesses ranging from cramps and exhaustion to potentially fatal heat stroke. Symptoms such as dizziness, fainting, nausea, vomiting, headaches, rapid heartbeat, and confusion should be treated as emergencies. Residents are advised to move quickly to a cooler environment, hydrate with water, and rest if they begin to feel unwell.

In the case of suspected heat stroke, caregivers are urged to call 911 immediately and take immediate steps to cool the affected person while awaiting medical help.

The warning is of particular concern to the elderly, infants, people with chronic health conditions, outdoor workers, and vulnerable populations such as the homeless and low-income households. Authorities are asking families and neighbours to check on those most at risk, noting that overnight conditions are also expected to remain uncomfortably warm, limiting recovery time from daytime exposure.

The Ministry of Health has placed hospitals and clinics on alert and is appealing to schools and employers to take precautions, including limiting outdoor activity and ensuring access to shade and water for students and workers.

Residents are strongly encouraged to stay indoors during the hottest parts of the day, wear light and breathable clothing, and drink plenty of water. The ABMS said it will continue to monitor the situation closely and provide updates through official channels.

Officials stressed that the current heatwave is not merely uncomfortable but a serious public health threat. “Extreme heat can be just as deadly as a hurricane or flood,” the agency warned. “Taking precautions now is the best way to protect yourself and your loved ones.”