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NWS St. Louis Announces Changes To May 16, 2025 Tornado Damage Assessment

After a year-long review of new ground survey data and aerial imagery, NWS St. Louis made several adjustments to the May 16, 2025 tornado damage assessment. Read More >

All three of the following criteria must be exceeded in order for Red Flag Warning conditions to be met:

  • Sustained 20 ft Winds: >15 mph
  • Relative Humidity: < 25%
  • 10 hr Dead Fuel Moisture: <9%

Below is a matrix that describes the Elevated Fire Danger criteria:

Elevated fire danger matrix for the St. Louis forecast area.