The ground is saturated in many US states amid flooding and further rain poses a greater risk.

The winter is reluctant to leave some parts of the United States, particularly the Dakotas.

After a late-season storm, Rapid City, South Dakota collected another 20cm of snow and measured 30cm lying on the ground, according to local meteorologist Jay Trobec.

Chicago, Illinois, picked up over five centimetres of snow from Winter Storm Xyler on Saturday. That’s the latest date for accumulating snow in more than 25 years and the latest calendar day on record with a five cm or more snowfall.

Thick ice was still piled up at the eastern end of Lake Erie in the last week of April, GOES-E satellite imagery shows. Surface water temperatures at Lake Erie’s eastern end continue to hover around 0 degrees Celsius, which has prevented ice from melting. According to Heather Waldman of WGRZ-TV in Buffalo, this cold has been recorded only 20 times in the last 92 years.

Very wet winter

Overall, the winter of 2018-19 was the wettest on record in the US after numerous heavy rain and snow events soaked the nation, NOAA reported in early March. A large swath of the US, the Plains, Midwest, South and East, as well as various parts of the West, has saturated soils.

Soil-moisture levels showed in the 99th percentile – that is in the top one percent – as of April 21 in portions of the upper Mississippi Valley, Plains, mid-South, Tennessee and Ohio valleys and mid-Atlantic.

These saturated soils are unable to absorb large amounts of rain, so any heavy-rain events in the months ahead will likely result in flooding.

Nearly two-thirds of the contiguous US faces an elevated flood risk through May, with the potential for moderate to major flooding in parts of 25 states, according to NOAA’s spring flood outlook issued last month.

Post-winter flooding

Detroit, Michigan just recorded a new daily rainfall record with 53mm on April 30. This is not a huge amount in a country such as the US, but for Detroit it ends the third-wettest April on record. The records go back to 1874. The city is now suffering severe flooding.

Asheville, North Carolina, had its wettest April on record with nearly 235mm. Boston, Massachusetts, recorded measurable rain on 20 days in April. That’s the record-most number of days with measurable rain in any calendar month of the year.

After tornadoes and hurricanes, flooding typically kills the second-largest number of people annually in the US, according to Chris Dolce of Weather Underground. Recent years have been especially deadly because of flooding. The three years spanning 2015 to 2017 had 187, 126 and 116 deaths, respectively.