Missouri MSHSAA Heat Policy and WBGT Guidelines
The Missouri State High School Activities Association (MSHSAA) sets heat limits for high school athletics by Wet Bulb Globe Temperature (WBGT). Here are the activity limits at each level, and how Sports Safe applies them to your fields.
Outdoor practice stops (Middle school)
90.1°F WBGT and above
Outdoor practice stops (High school)
92.1°F WBGT and above
Missouri WBGT activity chart
MSHSAA publishes separate charts for middle school and high school, and the middle school chart is stricter at every level above Green. School level belongs to the team, not the field, so Sports Safe asks which applies.
Middle school
No Flag
Under 82.0°F
Practice limit: None stated
Normal activities. At least three separate rest breaks each hour, minimum 3 minutes each.
Green Flag (low)
82.0 to 83.9°F
Practice limit: None stated
Use discretion for intense or prolonged exercise/practice; watch at-risk participants carefully. Separate rest breaks each hour, minimum 4 minutes each.
Yellow Flag (moderate)
84.0 to 86.9°F
Practice limit: 2 hours
Maximum practice time is 2 hours. All sports / marching band / spirit: at least four separate rest breaks each hour, minimum 4 minutes each.
Equipment: Football: helmet, shoulder pads and shorts only. If the WBGT rises to this level during practice, players may continue in football pants without changing to shorts.
Red Flag (high)
87.0 to 90.0°F
Practice limit: 1 hour
Maximum practice time is 1 hour. All sports / marching band / spirit: 20 minutes of rest breaks distributed through the hour. Games and performances: add official's timeouts for water breaks.
Equipment: Football: NO protective equipment may be worn, and NO conditioning activities.
Black Flag (extreme)
90.1°F and above
Practice limit: No outdoor practice
No outdoor workouts. Cancel or delay practice and competition until a cooler WBGT is reached. Indoor workouts may be permitted in an air-conditioned environment.
| WBGT | Level | Practice limit | What the chart says |
|---|---|---|---|
| Under 82.0°F | No Flag | None stated | Normal activities. At least three separate rest breaks each hour, minimum 3 minutes each. |
| 82.0 to 83.9°F | Green Flag (low) | None stated | Use discretion for intense or prolonged exercise/practice; watch at-risk participants carefully. Separate rest breaks each hour, minimum 4 minutes each. |
| 84.0 to 86.9°F | Yellow Flag (moderate) | 2 hours | Maximum practice time is 2 hours. All sports / marching band / spirit: at least four separate rest breaks each hour, minimum 4 minutes each. Equipment: Football: helmet, shoulder pads and shorts only. If the WBGT rises to this level during practice, players may continue in football pants without changing to shorts. |
| 87.0 to 90.0°F | Red Flag (high) | 1 hour | Maximum practice time is 1 hour. All sports / marching band / spirit: 20 minutes of rest breaks distributed through the hour. Games and performances: add official's timeouts for water breaks. Equipment: Football: NO protective equipment may be worn, and NO conditioning activities. |
| 90.1°F and above | Black Flag (extreme) | No outdoor practice | No outdoor workouts. Cancel or delay practice and competition until a cooler WBGT is reached. Indoor workouts may be permitted in an air-conditioned environment. |
High school
No Flag
Under 82.0°F
Practice limit: None stated
Normal activities. At least three separate rest breaks each hour, minimum 3 minutes each.
Green Flag (low)
82.0 to 86.9°F
Practice limit: None stated
Use discretion for intense or prolonged exercise/practice; watch at-risk participants carefully. Separate rest breaks each hour, minimum 4 minutes each.
Yellow Flag (moderate)
87.0 to 89.9°F
Practice limit: 2 hours
Maximum practice time is 2 hours. All sports / marching band / spirit: at least four separate rest breaks each hour, minimum 4 minutes each.
Equipment: Football: helmet, shoulder pads and shorts only. If the WBGT rises to this level during practice, players may continue in football pants without changing to shorts.
Red Flag (high)
90.0 to 92.0°F
Practice limit: 1 hour
Maximum practice time is 1 hour. All sports / marching band / spirit: 20 minutes of rest breaks distributed through the hour. Games and performances: add official's timeouts for water breaks.
Equipment: Football: NO protective equipment may be worn, and NO conditioning activities.
Black Flag (extreme)
92.1°F and above
Practice limit: No outdoor practice
No outdoor workouts. Cancel or delay practice and competition until a cooler WBGT is reached. Indoor workouts may be permitted in an air-conditioned environment.
| WBGT | Level | Practice limit | What the chart says |
|---|---|---|---|
| Under 82.0°F | No Flag | None stated | Normal activities. At least three separate rest breaks each hour, minimum 3 minutes each. |
| 82.0 to 86.9°F | Green Flag (low) | None stated | Use discretion for intense or prolonged exercise/practice; watch at-risk participants carefully. Separate rest breaks each hour, minimum 4 minutes each. |
| 87.0 to 89.9°F | Yellow Flag (moderate) | 2 hours | Maximum practice time is 2 hours. All sports / marching band / spirit: at least four separate rest breaks each hour, minimum 4 minutes each. Equipment: Football: helmet, shoulder pads and shorts only. If the WBGT rises to this level during practice, players may continue in football pants without changing to shorts. |
| 90.0 to 92.0°F | Red Flag (high) | 1 hour | Maximum practice time is 1 hour. All sports / marching band / spirit: 20 minutes of rest breaks distributed through the hour. Games and performances: add official's timeouts for water breaks. Equipment: Football: NO protective equipment may be worn, and NO conditioning activities. |
| 92.1°F and above | Black Flag (extreme) | No outdoor practice | No outdoor workouts. Cancel or delay practice and competition until a cooler WBGT is reached. Indoor workouts may be permitted in an air-conditioned environment. |
Key points
- The middle school chart is stricter at every level above Green: Yellow starts at 84°F instead of 87°F, and Black at 90.1°F instead of 92.1°F.
- Indoor workouts in an air-conditioned space may be permitted at Black flag.
Common questions
- At what WBGT does outdoor practice stop in Missouri?
- Using the MSHSAA heat policy, Sports Safe stops outdoor practice at 90.1°F WBGT on the middle school chart, and at 92.1°F WBGT on the high school chart.
- How long can practice last at each heat level in Missouri?
- Under the MSHSAA heat policy, the practice time limits are: Middle school chart: Yellow Flag (moderate), 84.0 to 86.9°F: 2 hours; Red Flag (high), 87.0 to 90.0°F: 1 hour. High school chart: Yellow Flag (moderate), 87.0 to 89.9°F: 2 hours; Red Flag (high), 90.0 to 92.0°F: 1 hour. Levels not listed have no time limit stated, and at the top level outdoor practice stops.
- Does Sports Safe use the heat chart for Missouri automatically?
- Yes. Sports Safe uses the MSHSAA charts for fields in Missouri. It asks whether each field follows the middle school or high school chart. You can choose a different chart for any field in its settings.
How Sports Safe uses the Missouri chart
Sports Safe estimates WBGT for each of your fields from current weather, checks it against this chart, and alerts you when a field moves into a stricter level. On the Organization plan, coaches can keep a timestamped log of meter readings and the actions taken.
An app estimate supports your decisions but is not a WBGT meter. Where your association requires readings from an approved instrument, use one for the reading of record.
Source
Summarized from the MSHSAA's published heat policy. View the source. Last reviewed October 3, 2026.
Sports Safe is not affiliated with or endorsed by the Missouri State High School Activities Association. Policies change, so always confirm the current rules with your association and follow your school's emergency action plan.