More rain is on the way on Wednesday and Thursday. A low pressure system will form in the central plains and move towards western Wisconsin. A warm front will serve as the trigger for some shower and thunderstorm development on Wednesday afternoon and evening, but a cold front isapproaching from the Plains later on Wednesday night through Thursday morning. The cold front will run into a very moist and unstable air mass, which will bring the threat for not only heavy rain, but severe weather. Rainfall amounts from 1 to 4 inches look likely for the Wednesday through Thursday. With the grounds well saturated south of I-90, much of this would runoff into rivers and streams already high with recent rainfall, leading to more river flooding, along with the increased probability of county-wide flooding.

Two days of heavy rains have lead to extremely high water on many area rivers and streams. Over 10 inches of rain has fallen in a few locations. The axis of the heaviest rainfall (8-10 inches by radar estimates) running along a St. Ansgar, IA to Eitzen to Viroqua, WI to Wisconsin Dells, rivers like the Turkey, Upper Iowa, Cedar and Kickapoo are experience flooding, some of which is approaching record levels.

CLICK HERE to see the National Weather Service rain totals.

From the National Weather Service:

Heavy rain threat returns for Wednesday and Thursday. A series of thunderstorms, some strong to possibly severe will move across the region on Wednesday and Thursday. All the storms will be capable of producing heavy rain with totals of 1 to 4 inches currently expected over the two days. With grounds saturated from the recent heavy rain along with some rivers just dropping below flood stage there will be a high risk for county-wide flash flooding and river flooding from any further heavy rain.

Tuesday night a thunderstorm complex will develop over South Dakota and western Minnesota tracking east along a warm front overnight and across the area Wednesday morning. This warm front should move north Wednesday afternoon while a cold front approaches from the west. Unstable and very moist air will surge ahead of the front fueling strong to severe thunderstorms from late Wednesday afternoon into Thursday. Again heavy rain will be possible with any of the thunderstorms with the greater severe threat Wednesday night and again on Thursday.

Affected counties: Mitchell, Howard, Winneshiek, Allamakee, Floyd, Chickasaw, Fayette, Clayton, Wabasha, Dodge, Olmsted, Winona, Mower, Fillmore, Houston, Taylor, Clark, Buffalo, Trempealeau, Jackson, La Crosse, Monroe, Juneau, Adams, Vernon, Crawford, Richland, Grant

Including the cities of Decorah, Waukon, Charles City, Oelwein, Rochester, Winona, Austin, Medford, Neillsville, Black River Falls, La Crosse, Sparta, Tomah, Mauston, Viroqua, Prairie du Chien, Richland Center, Platteville

Flash flood watch in effect from Wednesday morning through late Thursday night. The National Weather Service in La Crosse has issued a flash flood watch for portions of Iowa, southeast Minnesota and Wisconsin including the following areas:

In Wisconsin: Adams, Buffalo, Clark, Crawford, Grant, Jackson, Juneau, La Crosse, Monroe, Richland, Taylor, Trempealeau and Vernon.

In Iowa: Allamakee, Chickasaw, Clayton, Fayette, Floyd, Howard, Mitchell and Winneshiek.

In southeast Minnesota: Dodge, Fillmore, Houston, Mower, Olmsted, Wabasha and Winona.

From Wednesday morning through late Thursday night. Thunderstorms capable or heavy rain will return to the area for Wednesday and Thursday. Another 1 to 4 inches of rain will be possible over these two days. With grounds saturated and river levels high. Any additional heavy rainfall could result in flash flooding and further river flooding. A flash flood watch means that conditions may develop that lead to flash flooding. Flash flooding is a very dangerous situation. You should monitor later forecasts and be prepared to take action should flash flood warnings be issued.

From the AP:

Fixing the broken and nearly empty Lake Delton is only one of the flood-related challenges facing Wisconsin residents today. High water on Lake Delton near Wisconsin Dells tore a new channel to the Wisconsin River on Monday, emptying the lake and taking a few homes with it.

Now rising water of the Rock River near Johnson Creek east of Madison has threatened a bridge and shut down westbound lanes of Interstate 94 until further notice, forcing traffic to make a backroads detour.

State and local officials are monitoring various river dams where high water from days of rainstorms threaten to make them give way.

And the forecast includes what no one wants to hear -- more rain.

But meteorologist Bill Borghoff of the National Weather Service says the inch or two of rain expected to fall Thursday afternoon and night will likely lead to dry conditions Friday. And he says a dry spell could be coming after another weather system moves through over the weekend.

The flooding developed after downpours that saw Milwaukee set a record for the heaviest rainfall over a 48-hour period of just over seven inches.