Summer is associated with a number of different things, ranging from cookouts to swimming pools to Fourth of July fireworks. Of course, the summer months are also known for their hot temperatures. According to a 2019 report, the warnings that accompany heat waves are often not issued early enough.

Heat and Humidity

The report in question was a collaborative effort between Centers for Disease Control and Prevention and the National Oceanic and Atmospheric Administration, along with other federal agencies. Thanks to these organizations’ vast resources, the authors were able to review hospitalizations for heat-related illnesses over the span of a decade. Furthermore, they were also able to examine such data from 22 different states.

When it came to the Midwest and North Central regions of the United States, the researchers found that heat-induced hospital visits spike once the local heat index reaches 85 degrees. Such visits tended to result from dehydration, breathing difficulties, heart problems and even diabetes. Despite the threat posed by the humid weather, the researchers noted that these areas didn’t receive any first-level heat warnings until the heat index neared 100 degrees.

The news wasn’t all bad; in states located in the Eastern and Western regions of the US, warnings were issued only a few degrees past the 85-degree threshold. Furthermore, in the Southern US, heat related hospitalizations are typically preceded by heat advisory warnings.

Making Changes?

Given the study results detailed above, the National Weather Service pledged to review its heat warning process, hoping to determine if any changes can be made. As of early 2019, heat warnings are issued based both on a region’s heat index and the specific area in question. In the northern US, heat advisories are issued when the heat index reaches 100 degrees; at 105 degrees, heat warnings are issued. In the southern US, advisories and warnings are issued at 105 and 110 degrees, respectively.