Severe thunderstorm watch issued Tuesday afternoon

 8:35pm Update: The severe thunderstorm watch for Green, Rock, and Walworth counties has been canceled.

6pm Update: Other than a few sprinkles/light showers moving across northern Illinois the last couple of hours, the weather locally has been relatively quiet. However, to the north a line of severe thunderstorms continues to move east/southeast, closing in on south-central and southeast Wisconsin. Further to the west an isolated thunderstorm remains west of the Mississippi River in eastern Iowa.

Between now and 7pm the line of storms to the north should move further south, reaching parts of southern Wisconsin. With instability still around the threat for at least isolated severe thunderstorms, mainly in parts of Rock and Walworth counties, will continue. Instability does decrease slightly south of the state line in northern Illinois, and it is a little unclear at this time if the line of storms will hold together or begin to weaken after 8pm. Regardless, we should see at least a few scattered storms move south of the state line after 8pm. At that time, biggest threats will remain heavy downpours and gusty winds.

2:50pm Update: A Severe Thunderstorm Watch has been issued for the following counties in southern Wisconsin: Green, Rock, and Walworth, as well as for Jo Daviess and Stephenson counties in northwest Illinois until 10pm Tuesday.

Current radar as of 2:50pm shows a few spots worth discussing this afternoon. The first are the showers moving across south-central Wisconsin and north-central Illinois as of right now. These are not severe, and hold a very low risk of turning severe, as they move to the east/southeast.

Storms that are developing northwest of Dubuque could maintain some strength as they moving towards northwest Jo Daviess County within the next hour or two and pose a wind/hail threat.

Thunderstorms further to the northwest across central Wisconsin through La Crosse have formed ahead of the main cold front and, at the moment, hold the highest risk of severe. This line would move in later this afternoon - probably after 8pm or 9pm.

In the short-term - will be watching the second area of thunderstorms (near Dubuque) for an impact on northwest Illinois/southwest Wisconsin through 6pm.