A major insurance company is accusing dozens of localities in Illinois of failing to prepare for severe rains and flooding in lawsuits that are the first in what could be a wave of litigation over who should be liable for the possible costs of climate change. Farmers Insurance filed nine class actions last month against nearly 200 communities in the Chicago area. It is arguing that local governments should have known rising global temperatures would lead to heavier rains and did not do enough to fortify their sewers and stormwater drains.