The NWS Climate Prediction Center released their updated outlook for June, 2015. The new June outlook shows northern Illinois, including the Chicago area, with an increased chance of warmer and drier than average conditions.
Much of central and southern Illinois has equal chances (EC) of above, below, and near-average temperature and precipitation. This is different from the previous outlook for June that was released mid-May. That one had central and southern Illinois with an increased chance of wetter than average conditions.
While these outlooks cover the entire month, most of the model forecast skill is in the first 10 days. So the features of warmer and drier conditions in northern Illinois may be more in line with what’s expected in the first week or two and less with the entire month. More useful information can be obtained from the NWS 6-10 and 8-14 day forecasts which are updated daily.