Red Flag Warning for Larimer and Boulder Counties in Colorado
This alert is no longer in effect.
NOAA issued it on April 30, 2026, 3 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).
Areazine synthesizes this NWS weather alert directly from NOAA's official public data feed. See our methodology for full source attribution and refresh cadence.
A Red Flag Warning has been issued for Larimer and Boulder Counties between 6000 and 9000 feet in Colorado, effective from 10 AM Wednesday due to strong winds and low humidity that could lead to rapid fire spread.
Read this weather record in 30 seconds
- Record type
- Red Flag Warning
- Affected area
- Northern Colorado Foothills
- Issued
- April 30, 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 3 months ago; use the issuing agency's live warning service for current conditions in Northern Colorado Foothills.
Red Flag Warning in Colorado
Alert Details
The National Weather Service in Denver has issued a Red Flag Warning for wind and low relative humidity. This alert is effective from 10 AM MDT on April 22, 2026, until midnight MDT on April 23, 2026.
Affected Areas
The warning affects Larimer and Boulder Counties between 6000 and 9000 feet, specifically Fire Weather Zone 215 in the Northern Front Range Foothills of Colorado.
What You Should Do
Residents should prepare for critical fire weather conditions. Avoid outdoor burning and any activity that may produce a spark and start a wildfire.
Expected Conditions
Winds are expected to be southwest at 20 to 30 mph with gusts up to 45 mph. Relative humidity will be as low as 10 percent, creating conditions favorable for rapid fire spread.
Timeline
The alert is in effect from 10 AM MDT on April 22, 2026, and ends at midnight MDT on April 23, 2026.
Original source: NOAA Official Notice ↗
Related Weather Alerts
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Two Areazine-derived peer sets for this NWS weather alert: nearest notices by body length and by same severity near the same agency date. Peers come from other categories so they are not the same-feed Related list above.
Similar body length
Nearest notices by article body length (918 characters here).
Similar severity timing
Same severity (high) notices issued closest in time to April 30, 2026.
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