Flash Flood Risk High in Boulder, Larimer County From Spring Runoff
A combination of higher than average snowpack and saturated ground from the September 2013 flood has raised the risk of spring runoff flooding in the Saint Vrain, and Boulder Creek, Big Thompson and the upper Cache La Poudre River drainages.
The current high country snowpack is already approximately 116 percent of the typical seasonal peak, with roughly 15 percent of the snow accumulation season remaining, according the National Weather Service update.
The percentage of average mountain snowpack in the South Platte River Basin in 2014 is the third highest in the past 35 years. Only March of 1986 and 1996 were higher.
It’s not just the mountains and foothills that could be impacted. The NWS says that “the flood risk is somewhat elevated in southwest Weld County, and also along the lower Cache La Poudre River in eastern Larimer and western Weld Counties due to flooding last September.”
The risk of spring snowmelt flooding is high elsewhere in the north central mountains and northern Colorado Front Range due to the above average snowpack.
Some reservoirs in these areas are at or near capacity and will spill earlier than usual causing additional flow during the runoff and thunderstorm season.