Originated by Mark Zilis of T&Z or Q&Z Nursery in Illinois and the Northern Illinois Hosta Society, this non-registered cultivar is a tissue culture sport of H. 'How About That!. It is a giant size hosta which is related to H. 'Sum and Substance' and H. 'Sum It Up'. It has very large, nearly round, light green foliage with "the best white margin of the group". Pale lavender, tubular flowers bloom from July into August.

'Windy City' was introduced at the 2022 Midwest Hosta Society Regional Convention.