The day featured an impromptu chase. There was a chance for some storms, but nothing significant was expected. During the late afternoon a storm developed near the intersection of a southeastward moving boundary and a southwestward moving lake breeze. The storm stuggled for a while as it passed east of Rockford, but before too long it matured and strengthened. Given it wasn't too far away and it was moving southeast towards my general direction, I decided to head west and make a play on it. While heading west the storm continued to strengthen and showed some mid-level rotation, as it pushed southeast long the intersection of the boundary and lake breeze. After jumping around and trying to get ahead of it, I let the storm pass over as I sat near South Elgin. The storm featured hail up to around penny size, near 60mph winds, tons of CTG lightning and heavy flooding rains.