Updated flood outlook indicates higher risk of major spring flooding

The National Weather Service released its second spring flood outlook of the season on Thursday. The first flood outlook from two weeks ago showed a much higher than average risk of spring flooding, and that risk has gone even higher with this update for nearly all of the local river forecast locations. That includes the potential to reach major flood stage. This is because additional heavy snow has fallen upstream across Minnesota and Wisconsin. There is a chance that locations along the Mississippi River could experience near-record or record flooding this spring depending on how fast the snow melts and how much rain falls. If the snow melts slowly or little rain falls, then that risk is lower.

It’s important to note that this outlook is for spring flooding and doesn’t necessarily mean anything about the risk of summertime flooding. Spring flooding can make it easier for flooding to happen in the summer, but that is not always what happens.

Below are the flood chances for the river forecast locations for our local basins, compared to the historical average. It compares the odds for reaching minor, moderate, and major flood stage.

Lansing:

Minor – 93% (average: 10%)

Moderate – 70% (average: 8%)

Major – 55% (average: Less than 5%)

McGregor:

Minor – Greater than 95% (average: 51%)

Moderate – Greater than 95% (average: 23%)

Major – Greater than 95% (average: 9%)

Guttenberg:

Minor – Greater than 95% (average: 40%)

Moderate – Greater than 95% (average: 10%)

Major – 70% (average: Less than 5%)

Dubuque:

Minor – Greater than 95% (average: 49%)

Moderate – Greater than 95% (average: 39%)

Major – Greater than 95% (average: 11%)

Bellevue:

Minor – Greater than 95% (average: 32%)

Moderate – Greater than 95% (average: 19%)

Major – Greater than 95% (average: 10%)

Charles City:

Minor – 85% (average: 20%)

Moderate – 69% (average: 10%)

Major – 56% (average: 6%)

Janesville:

Minor – 61% (average: 7%)

Moderate – 31% (average: Less than 5%)

Major – Less than 5% (average: Less than 5%)

Cedar Falls:

Minor – Greater than 95% (average: 44%)

Moderate – Greater than 95% (average: 2%)

Major – 64% (average: 10%)

Waterloo:

Minor – Greater than 95% (average: 30%)

Moderate – 42% (average: 6%)

Major – 22% (average: Less than 5%)

Vinton:

Minor – Greater than 95% (average: 20%)

Moderate – 50% (average: 8%)

Major – 36% (average: 6%)

Palo:

Minor – Greater than 95% (average: 30%)

Moderate – 44% (average: 7%)

Major – 23% (average: Less than 5%)

Cedar Rapids:

Minor – Greater than 95% (average: 32%)

Moderate – 93% (average: 19%)

Major – 66% (average: 9%)

Cedar Bluff:

Minor – Greater than 95% (average: 32%)

Moderate – 61% (average: 9%)

Major – 9% (average: 6%)

Conesville:

Minor – Greater than 95% (average: 56%)

Moderate – Greater than 95% (average: 22%)

Major – 52% (average: 8%)

Marshalltown:

Minor – 77% (average: 9%)

Moderate – Less than 5% (average: Less than 5%)

Major – Less than 5% (average: Less than 5%)

Tama:

Minor – Greater than 95% (average: 22%)

Moderate – 89% (average: 14%)

Major – 33% (average: Less than 5%)

Marengo:

Minor – Greater than 95% (average: 67%)

Moderate – Greater than 95% (average: 48%)

Major – 38% (average: 6%)

Iowa City:

Minor – 21% (average: 6%)

Moderate – 16% (average: Less than 5%)

Major – Less than 5% (average: Less than 5%)

Lone Tree:

Minor – 30% (average: 14%)

Moderate – 8% (average: 6%)

Major – Less than 5% (average: Less than 5%)

Columbus Junction:

Minor – 74% (average: 14%)

Moderate – 36% (average: 5%)

Major – 20% (average: Less than 5%)

Independence:

Minor – 27% (average: 8%)

Moderate – 13% (average: 7%)

Major – 7% (average: Less than 5%)

Anamosa:

Minor – 89% (average: 26%)

Moderate – 25% (average: 12%)

Major – 7% (average: Less than 5%)

Kalona:

Minor – Greater than 95% (average: 48%)

Moderate – 31% (average: 33%)

Major – 9% (average: 13%)

Sigourney:

Minor – 78% (average: 55%)

Moderate – 51% (average: 40%)

Major – 12% (average: 11%)

Oskaloosa:

Minor – Less than 5% (average: Less than 5%)

Moderate – Less than 5% (average: Less than 5%)

Major – Less than 5% (average: Less than 5%)

Manchester:

Minor – 50% (average: 22%)

Moderate – 21% (average: 16%)

Major – 12% (average: 8%)

Maquoketa:

Minor – 67% (average: 18%)

Moderate – 48% (average: 13%)

Major – 26% (average: 8%)

Elkader:

Minor – Greater than 95% (average: 43%)

Moderate – 89% (average: 22%)

Major – 67% (average: Less than 5%)

Garber:

Minor – Greater than 95% (average: 38%)

Moderate – 89% (average: 23%)

Major – 77% (average: 14%)

Decorah:

Minor – Less than 5% (average: Less than 5%)

Moderate – Less than 5% (average: Less than 5%)

Major – Less than 5% (average: Less than 5%)

Dorchester:

Minor – Greater than 95% (average: 20%)

Moderate – 83% (average: 7%)

Major – 56% (average: Less than 5%)