Do reports of this repair follow the weather where owners live, county by county?

Across 48 U.S. counties with 10 or more NHTSA owner complaints about windshield wiper blade replacement, reports run 68% above the national share in the third with the coldest winters against 23% below in the third with the mildest winters. This is an association across counties, not a cause.

Reports of windshield wiper blade replacement by county, grouped by winter cold (heating degree days). Third of counties with the mildest winters: 23% below; Middle third: 43% above; Third with the coldest winters: 68% above.

• Split the 48 counties into thirds by winter cold (heating degree days): the third with the mildest winters reports windshield wiper blade replacement 23% below what the national share predicts, the middle third 43% above, and the third with the coldest winters 68% above.
• Take out any single county and the pattern still holds; the one it leans on most is McHenry County, IL.
• Weak spot: compare only counties with similar summer heat (cooling degree days) and the pattern keeps about 54% of its strength, so part of it may come from that instead.
• Still open: complaint city names are matched to counties by place name, so a county with postal-neighbourhood names is undercounted, and county elevation is the height of one point, not the county average.

Weather and roads act on a car where it is driven, not on a state average, so the county map tests the same mechanism more closely.

Source: NOAA NCEI nClimDiv county climate files 1991-2020, joined to NHTSA owner complaints placed in counties by city name · file downloaded 2026-10-05