Just a day after tornadoes touched down in the Denver metro area, another wave of dangerous weather swept into northern Colorado, this time, hitting close to areas swamped in what was described as "biblical flooding" last fall.

Cities north of Denver were already dealing with major flooding by Tuesday evening.

The National Weather Service in Boulder estimates between 3-5 inches of rain fell across eastern Larimer and western Weld counties in just a few hours. Interstate 25 in the Loveland/Fort Collins was at a standstill in several places, according to 9 News in Denver. In Harvard Gulch Park, two girls were stranded and one had to be rescued by rope. 

Photos show stalled cars in high water in the town of Windsor, about 15 miles southeast of Fort Collins. NWS reports police are calling for barricades.

The last week of July into the first few weeks of August have seen some of the deadliest flooding on state record, CBS Denver reports.

The area hit hard Tuesday is about 30-45 miles north of where heavy rain decimated homes and businesses and killed 10 people along the Denver Front Range in September 2013.

Forecast: Flash Flood Threat This Week

Flash flood watches in effect are illustrated by the green-shaded areas in the map above.

Slow-moving thunderstorms with heavy rainfall will soak parts of Colorado and New Mexico through Thursday. Flash flooding is already a concern, especially on and near burn scars from recent years' wildfires. Rainfall totals could exceed four inches in a short period of time, in some areas.

Be alert to the potential of dangerous rushing water and landslides in any areas where heavy rain falls in steep terrain. Even the heaviest passenger vehicles can be swept away by two feet of moving water. Six inches of rushing water can knock you off your feet. Do not drive through flooded areas.

MORE ON WEATHER.COM: 2013 Devastating Colorado Flooding