A band of very heavy snowfall, including thundersnow with rates up to 2 inches per hour, is combining with northeasterly winds gusting up to 50 mph to produce life-threatening blizzard conditions from Nebraska into northern and western Iowa today. Extreme caution is advised in these areas through the rest of the day and into tonight. Major interstates such as I-70 and I-80 have been or will be closed.
Conditions are gradually improving in eastern Colorado as snow winds down, but many major highways and interstates, including I-70, remain closed and impassable due to whiteout conditions last night and this morning. Near-zero visibilities and high drifts will continue to make travel virtually impossible from Nebraska into parts of Iowa through today. Snowfall totals in these areas will approach or exceed one foot with drifts of several feet in spots. The storm is expected to slowly weaken as it moves towards the western Great Lakes tonight, however moderate to heavy snow and dangerous conditions will still occur from southeastern Minnesota into south-central Wisconsin.