Feeling Hot, Hot, Hot - Summer in Evansville

Feeling Hot, Hot, Hot - Summer in Evansville 

Carlisle Wishard, Director of Science Experiences

The national forecast for August 4 - August 8, 2023. Source: The National Weather Service.

In case you haven’t had the chance to step outside in the past few weeks, let me be the first to tell you, it is HOT. As we have seen over the course of the summer, much of the world is facing dangerously high temperatures. The first week in July was the hottest week ever recorded, according to the World Meteorological Organization. Exacerbated by climate change, typically high summer temperatures are pushed well above the norm, creating heat emergencies across the United States. Here in Evansville, today may actually be one of the coolest days we have seen in the past few weeks, but it is likely to get back up into the 90s again in just a few days. 

As a newcomer to Evansville, I wondered if this was a typical summer here in the city, or if the high temperatures we are experiencing are uncommon, as they are for much of the country. So, like any good scientist would do, I took a deep dive into the National Weather Service’s database to find the answers (explore the database yourself at https://www.weather.gov/pah/EvansvilleDailyNormalsAndRecords). 

I discovered that the average annual daytime temperature in Evansville in the summer months is around 90 degrees. In fact, the high temperatures we have experienced this summer don’t even come close to some of the record high temperatures experienced in Evansville in the past. Over the past 30 years, the highest temperature recorded in Evansville occurred on July 5th, 2012, when temperatures reached a record 107 degrees! In fact, 2012 was an unusually hot summer for Evansville, with 8 days in July breaking local records.  

Average Temperature July 2012: 97.3 F Average Temperature July 2023: 89.6 F

So why are people in the south and western parts of the country facing such unusually high temperatures this summer, while Evansville appears to be mostly spared? The answer may be a complicated mix of climate change, ocean currents, and our location along the Ohio River. 

The year 2023 marks the start of another El Niño event, a period of ocean warming that occurs approximately every 2-7 years. The last El Niño event occurred in 2018-2019. During an El Niño event, warm water in the Pacific Ocean is pushed towards the west coast of North America, causing hot, dry weather in the Pacific Northwest and upper midwest. Wetter weather is pushed south, causing widespread flooding across the southern United States and northern Mexico. Here in Evansville, we are situated between the hot weather to our north and the wet weather to our south, allowing us to remain relatively insulated from the effects of El Niño. 

The effects of El Niño can combine with high pressure systems here on land to form an atmospheric phenomenon called a heat dome. This causes hot air to become trapped on land, sometimes for weeks on end. Lingering heat domes have caused waves of high temperatures to scorch much of the southern United States in the past few weeks.

Human caused climate change is also exacerbating heat waves across the globe. As we burn fossil fuels, greenhouse gasses (particularly carbon dioxide) get up into our atmosphere and trap the Sun’s heat, preventing the Earth from cooling off. As the Earth warms, traditionally stable climate systems become unbalanced, causing extreme weather across the globe. 

Here in Evansville, we feel the effects of climate change less strongly than they do in other parts of the country, due primarily to the geologic location in which our city is situated. We are located far from the ocean, meaning we are less affected by hurricanes that are intensified by climate change. We are not located in a cold climate, so we don’t see the melting of long-frozen ice and the shrinking of glaciers. We do not live in an arid climate, where climate change is causing rain to be so infrequent that droughts are becoming the norm. Instead, we are located inland, along the placid Ohio River. Rivers have a stabilizing effect on the local climate, cooling us in the summer and keeping us warm in the winter. 

The Ohio River, as seen from the back garden of the Evansville Museum, on July 30th, 2023.

So while we may not be experiencing a heat wave here in Evansville, the high temperatures we can expect for the remainder of the summer are still important to keep in mind. To protect yourself, your family, and your pets this summer, the CDC recommends staying in air-conditioned buildings as much as possible, along with drinking plenty of water, wearing light colored and loose-fitting clothing, and limiting the use of devices that heat up your home, such as the oven or stove. If you know a neighbor or loved one does not have air-conditioning in their home, be sure to check in on them, encourage them to seek an air-conditioned building during the hottest parts of the day, or invite them to spend time with you out of the heat. 

So stay safe and enjoy the summer, Evansville! And if you are looking for an afternoon activity to get you out of the heat, stop by the Evansville Museum and experience our wonderful air-conditioned exhibits and immersive theater.