The Upper Midwest is no stranger to harsh winters, but summer can be just as tough on your parking lot. In Minnesota and Wisconsin, summer brings high temperatures, intense UV exposure, and heavy rainfall, all of which take a toll on asphalt and concrete surfaces.
At ACI Asphalt, we’ve spent over 30 years helping commercial property owners protect and preserve their pavement investments across the region. Here’s what you need to know about summer-related pavement stress, and how you can proactively mitigate damage with proper maintenance.
What Summer Does to Your Parking Lot in the Upper Midwest
1. UV Rays Accelerate Surface Aging
Just like in the winter, the sun doesn’t play nice. Ultraviolet radiation during long summer days breaks down the chemical bonds in asphalt, causing oxidation. This results in brittle, dry pavement that loses flexibility and develops surface cracks, especially in older lots.
2. Temperature Swings Cause Expansion and Cracking
Although summer brings warm days, nighttime temperatures in the Midwest can drop significantly. These daily swings cause expansion and contraction in pavement surfaces, opening the door for cracks and structural fatigue.
3. Intense Rain and Humidity Increase Water Damage Risk
Heavy summer storms and flash flooding are common in Minnesota and Wisconsin. When water enters cracks and doesn’t drain properly, it can damage the base layer beneath your parking lot, eventually causing potholes, depressions, and surface erosion.
4. Asphalt Softening and Rutting
While Midwest summers are relatively short, the heat can still cause asphalt to soften, especially during July and August when temperatures routinely rise above 85°F. Combined with heavy vehicle loads, this softening leads to permanent impressions and surface rutting.
Essential Summer Maintenance Tips for Midwestern Parking Lots
1. Apply Sealcoat Protection
Sealcoating your lot adds a layer of UV resistance and water protection while giving your surface a clean, dark appearance. In the Midwest, the best time to sealcoat is typically between May and September, when temperatures stay above 50°F and humidity levels are manageable.
2. Perform Timely Crack Sealing
Cracks expand in the summer and become worse with rain infiltration. ACI Asphalt uses hot-pour crack sealing methods designed for Midwest weather, preventing water from getting below the surface and causing freeze-thaw damage later in the year.
3. Re-stripe and Repaint Pavement Markings
Bright, clear striping is important for safety and compliance. Sun exposure fades parking lines, arrows, and ADA markings over time. Summer is the perfect season to refresh striping while conditions are dry.
4. Clean and Maintain Drainage Features
Clogged or poorly designed drainage systems allow water to pool, especially during the sudden, heavy thunderstorms common in Wisconsin and Minnesota summers. Regular inspection of storm drains, gutters, and slopes ensures your lot stays dry and damage-free.
5. Limit Traffic Stress in Vulnerable Areas
If your lot serves delivery trucks or high-weight vehicles, consider reinforcing high-stress areas or diverting traffic. Midwestern heat, combined with vehicle pressure, increases the likelihood of rutting and base layer failure.
Trust ACI Asphalt for Expert Pavement Care in Minnesota and Wisconsin
The freeze-thaw cycle gets all the attention, but summer conditions in Minnesota and Wisconsin can be equally punishing. ACI Asphalt recommends conducting summer maintenance now to avoid bigger issues in fall and winter. Preventative measures taken during the warmer months can extend your pavement’s lifespan by years and drastically reduce repair costs.
From St. Paul to Eau Claire, and everywhere in between, ACI Asphalt has the knowledge and equipment to keep your lot protected, professional-looking, and structurally sound. Our experienced crews specialize in summer sealcoating, crack filling, resurfacing, and striping, all tailored to the unique needs of the Upper Midwest.
Contact us today to schedule a no-obligation inspection and receive a customized maintenance plan for your property.