The first round of what's expected to be multiple thunderstorms rolled into the Front Range Monday afternoon, bringing heavy rain, hail and lightning to places ranging from Boulder to Parker.
A flash food warning was issued for the Foxfield area in southwestern Arapahoe County. It has since expired.
Castle Rock already experienced local flooding and a wall collapse due to the storm. Water was seen in the road near the city's outlet mall.
The storms brought accumulated hail to Keenesburg in Eastern Colorado, as well as a tornado warning in Kiowa County, where spotters saw a funnel cloud.
The biggest threat in the Eastern Plains will be large hail up to two-inches in diameter and winds up to 60 mph through the evening.
Denver International Airport told travelers to expect delays.
A 9NEWS viewer in Erie watched as hail destroyed her garden.
Severe storms are also possible in far southeastern Colorado on Monday evening.
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