National Weather Service warns of flooding

The National Weather Service has issued a warning that northeast Wyoming is likely to experience greater than average levels of flooding this spring. River basins in Crook County that may be affected include the Little Missouri and Belle Fourche.

The above-average flooding is expected to continue through June in some parts of the Rapid City Hydrologic Service Area, which covers northeastern Wyoming and western South Dakota. The causes include saturated soil conditions, high river levels and the potential for ice jam-related flooding.

In the Black Hills, flooding generally begins in late April and May, while flooding from snowmelt and ice jams typically takes place from February to May. The flood potential is dependent on weather conditions going into spring as the amount of additional snow and rain will affect severity.

Since October, the National Weather Service reports that temperatures seem to have been below average and precipitation has varied from below to above average in the Black Hills. However, the data was skewed by very cold conditions in October and November; since December, temperatures have been above average by three to five degrees.

Snow depths in the Black Hills and Bear Lodge Mountains are believed to range from one to three feet with the liquid content ranging from three to six inches. March and April are typically the two snowiest months.

Soil moisture is meanwhile above average at 99% but the amount of frost in the ground is below average at less than a foot of frost depth in the Black Hills area. Almost all lakes in the Black Hills are ice covered, but some prairie ponds only have minimal ice thickness due to the warmer temperatures.