Red Flag Warning Issued for Larimer, Boulder, and Jefferson Counties Through Thursday Night
This alert is no longer in effect.
NOAA issued it on April 6, 2026, 4 months ago. Warnings of this kind stay in effect for hours to a few days, so this page is a historical record of what was issued, not a current warning. For conditions where you are right now, check weather.gov (US), weather.gc.ca (Canada), the Met Office (UK), or the Bureau of Meteorology (Australia).
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The National Weather Service has issued a Red Flag Warning for the Colorado urban corridor due to high winds and low humidity, effective Thursday.
Read this weather record in 30 seconds
- Record type
- Red Flag Warning
- Affected area
- North Central Colorado
- Issued
- April 6, 2026
- Issuing authority
- NWS Denver CO
Fire-weather notices describe conditions that can support rapid fire spread; they do not report that a fire is present. Check local emergency sources for any active incident.
Record status: historical. It was issued 4 months ago; use the issuing agency's live warning service for current conditions in North Central Colorado.
Alert Details
The National Weather Service in Denver has issued a Red Flag Warning for wind and low relative humidity. This alert replaces the previous Fire Weather Watch for the region.
Affected Areas
The warning covers Fire Weather Zones 238 and 239, which include the following geographic regions:
- Larimer County below 6,000 feet
- Northwest Weld County
- Boulder and Jefferson Counties below 6,000 feet
- West Broomfield County
What You Should Do
Residents in the affected areas should avoid all outdoor burning and any activities that may produce a spark and start a wildfire. A Red Flag Warning indicates that critical fire weather conditions are either occurring now or will shortly. The combination of strong winds, low relative humidity, and warm temperatures can contribute to extreme fire behavior and rapid fire spread.
Expected Conditions
- Winds: West winds of 25 to 40 mph are expected, with gusts up to 75 mph possible.
- Relative Humidity: Levels are forecast to drop as low as 15 percent.
- Impacts: Conditions will be highly favorable for the rapid spread of any fires that ignite.
Timeline
The Red Flag Warning is effective from 11:00 AM to 9:00 PM MDT on Thursday, March 12, 2026.
Original source: NOAA Official Notice ↗
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