Hot Holiday Ahead
We will see brief and marginal relief from this oppressive heat, but it rears its ugly head again near Independence Day. As you have noticed these last few days, the Heat Index is a critical factor to watch.
The Weather Prediction Center has put out guidance for maximum heat indices surrounding the Fourth of July. When the National Weather Service is considering heat-related alerts, they look for threshold values which are different at each local office. 105º maximum heat index is a big number for each office, whether that's criteria for a Heat Advisory or for an Excessive Heat Watch/Warning.
The blue box below is the Weather Prediction Center's analysis of how likely it will be for Louisville (specifically the SDF airport) to exceed specific values of a maximum heat index. They are forecasting a maximum heat index of 109º and showing a better than a 2/3 chance the heat index will be higher than 105º.
WDRB will keep you informed if any heat alerts are issued or if we feel the heat will be a threat to your health and safety. Please drink LOTS of water, especially if you choose to drink soda or adult beverages during the Fourth of July. Those will dehydrate you even more. Know the symptoms of heat-related illness so you can monitor yourself and those around you.