The United States National Weather Service has said that the dangerous heat wave that has lead to a number of deaths is expected to continue across much of the central and eastern United States, with excessive heat and humidity expanding into the Ohio Valley and East Coast states for the remainder of the week. The highest heat index values are excepted across parts of the Midwest, Ohio Valley and Mid-Atlantic, where they are forecast to be between 105 and 115 degrees through Friday, with locally higher values possible. Excessive Heat Watches, Warnings and Heat Advisories are in effect over much of the central U.S., Ohio Valley and from the Carolinas northward into New England.
Heatwaves can be dangerous, especially for the very young, the very old or those with a chronic disease. Prolonged exposure to very high temperatures can mean the body is unable to reduce its own temperature, causing dehydration and heat stroke, which can be fatal. In particular, hot temperatures overnight make it difficult for the body to cool.
The Met Office forecasts day-time and night-time maximum temperatures. These are monitored regionally. When certain heat thresholds are passed, a warning is sent to relevant health professionals and people working in social care, so they can take action to minimise the impact of the heat on the health of people in their area.