Time: 956 AM Sun May 2, 2021 Forecaster: Brad Simmons

Flash Flood Prediction Program


We have determined that street and small stream flooding is possible in the following counties: Boulder (City of Boulder affected, Four Mile Burn Area affected), Jefferson, Broomfield, Douglas, Adams, Denver, Arapahoe
including: DIA, the City of Aurora, Arvada, Wheat Ridge, Lakewood
from: Current to 800 PM.
Prime time for flooding: 1100 AM to 700 PM.
Forecast rainfall: Moderate to strong thunderstorms will have the potential to produce 0.3-0.9" of rain in 10-30 minutes. Training of moderate/strong thunderstorm cells may result in up to 1.6" of rain in 60-90 minutes.
The most likely areas to be impacted by flooding are:

X Urban streams/gulches; road crossings; recreational trails; adjacent open space areas/campgrounds/parks; floodplain properties; utilities

X Urban streets, intersections, low lying areas, known trouble spots

Additional Information: Strong thunderstorms may also contain large hail, gusty winds and frequent cloud-to-ground lightning.

This message is not intended for public dissemination. Please pass this information along to affected emergency response organizations (police, fire, public works, etc.) within your area.

Also, please take appropriate actions to prepare for possible flooding.

Further information will be provided to you as it becomes available.