Heavy rains expected later Friday/Friday night – Flash Flood Watch in effect for western portions of the Chicago area
A Flash Flood Watch is in effect for Winnebago, Boone, Ogle and Lee Counties Friday afternoon and Friday night. The Flash Flood Watch is also in effect for areas to the west into Iowa and north into Wisconsin (dark-green-shaded counties on the headlined map).
As low pressure moves out of the central plains, heavy rains are expected to develop over Northeast Iowa and northwest Illinois into southwest Wisconsin later Friday and Friday night. Thunderstorm downpours could “train” – continually develop and track across the same area with maximum runoff potential due to already swollen rivers and saturated soils. One to three-inches of rain with locally higher totals are likely.
Note on the Excessive Rainfall map below – the Moderate Risk for localized flooding depicted by the red “bulls-eye” over the area under the Flash Flood Watch. Of added significance, heavy rains could spread east over the remaining portion of the Chicago area, and note a good portion of the Chicago area is under a Slight Risk of Excessive rain and localized flooding (yellow-shaded area)– mainly north of Interstate-80 where a few rivers are in currently in flood and soils also nearly saturated.
Excessive Rainfall map for Friday/Friday night…