The warm front associated with the strong low pressure system passed through the Chicago area between 2 and 3AM on it’s way north and at 6AM is oriented east-west along the Illinois-Wisconsin state line. South of the front south to southwest winds 15 to 28 mph and temperatures in the upper 50s prevail – Wheeling actually reported 60-degrees at 6AM. North of the front through southern Wisconsin and farther north, winds were east to southeast and temperatures in the 30s. Milwaukee at 6AM was 37 degrees.
A north-south cold front extending from eastern Wisconsin - eastern Iowa into northwest Missouri us moving slowly east and will eventually pass through the Chicago later tonight/early Wednesday morning. Strong southerly winds will continue to push moisture-laden air into the Chicago area today and with the potential for 1 to 3-inch rains, the Chicago National Weather Service has issued a Flood Watch for the entire Chicago area for this afternoon and tonight. Actually In addition to northeast Illinois and northern Indiana, A Flood Watch is also in effect for southeast Wisconsin, Central Illinois and Indiana and much of Lower Michigan (as shown on the map below in green –portions of those same areas are in grey under Dense Fog Advisories this morning). Freezing Rain Advisories are in effect across northern Wisconsin with accumulating snow expected farther west in Iowa and Minnesota.