It's shaping up to be one of the hottest Memorial Day weekends ever in Michiana. Not only will actual air temperatures soar into the upper 80s and lower 90s, but the humidity will be quite high as well. Dew points will be well into the 60s, making it feel muggy all weekend long. When you factor highs near 90° with dew points in the 60s, the end result will be heat index temperatures near 90° Saturday. For Sunday and Monday, most locations away from Lake Michigan will see heat indices in the middle 90s, if not a little hotter. If you're looking for relief this weekend, a lake breeze will provide much cooler temperatures from Michigan City to New Buffalo, St. Joseph and South Haven.
Despite it being the hottest stretch of the year by far, we won't quite meet the criteria for Heat Advisories or Excessive Heat Warnings. Those alerts are only issued when heat indices rise toward 100°. Michiana will likely fall just short of that. However, it will be hot enough for heat exhaustion and heat stroke to be potential issues. That is especially true for children, the elderly and those who struggle in the hot conditions.
Both heat exhaustion and heat stroke are dangerous, with heat stroke potentially being deadly. The problem is most people don't know the key differences between the two. Heat exhaustion causes dizziness, excessive sweating, cool and clammy skin, nausea, vomiting, a rapid, weak pulse, and muscle cramping. Meanwhile, heat stroke is known for causing a throbbing headache, a lack of sweating, body temperatures above 103°, hot and dry skin, nausea, vomiting, a rapid, strong pulse, and the loss of consciousness. If you are outdoors and someone begins to experience the symptoms of heat exhaustion, they need to be moved to a cool place, have their clothes loosened, sip water, and use wet cloths on their skin. If someone may be suffering from heat stroke, it is highly recommended to dial 9-1-1 immediately while moving them to a cooler place. Never give someone who may be experiencing heat stroke something to drink.
In terms of how long the heat will last, we may not see afternoon highs drop below 80° until June 4th or so. If we see at least 80° each afternoon up until that day, it would be the first stretch of at least 11 days at or above 80° since August of 2016! The longest such stretch in 2017 was 10 days. The hottest air temperatures over the course of this impending heat wave will likely occur Sunday thru Tuesday with highs around 90°. There are a few chances for rain and storms by the time we get to the May 31st - June 3rd period, which could keep us below 80°.