1. Prescriptions
Gary Jarvis
Fire Planner
National Forests in Mississippi

2. Demonstrate how to develop prescribed burn parameters
Key Points
Demonstrate how to develop prescribed burn parameters
2.Demonstrate how to use the
BEHAVE program when developing a prescription.

3. 5142.3 – Pre-Ignition Briefing and Forecast Requirements
1. Utilize the most current fire weather forecasts and spot weather forecasts in making pre-ignition decisions. Use the National Weather Service (NWS) or other reputable source (Forestry Commission or SRI meteorologists for example) for fire weather and spot forecasting.
2. Place 10-hour fuel moisture sticks on or near prescribed burn units (or cluster of prescribed burn units) to determine fuel moisture. Each Forest should develop fuel-stick moisture values that provide for the accomplishment of specific resource objectives. Refer to 5140 Exhibit 02, Standards for Prescribed Fire Parameters for the regional standards for fuel moisture.
3. A fire weather forecast from the NWS or other reputable source with 20-foot wind speeds predicted between MPH is accepted as compliant with the Regional maximum standard of 18 MPH. Gusts are to be considered as part of the forecast. Predicted 20-foot wind gusts over 20 MPH are out of prescription with regard to wind.
4. Fire weather forecast items should include maximum temperature, minimum relative humidity, maximum 20 foot wind speed-direction (a.m./p.m.), transport wind speed-direction, mixing height, smoke dispersion index, ventilation rate or category day, sky condition, probability of precipitation-duration-amount, frontal passages, and severe weather outlook. Provide feedback to the fire weather forecaster for their fire weather forecasts. Attach forecasts to RxBP.

4. NF in Mississippi Supplement 5140-93-27
Parameters - Dormant Season – Understory
Temperature: <= 72
RH: 30-60%
20ft wind speed: 5-15mph
10 hr fuel moisture: 7-15%
KDBI: <300
Ignition probability: <60
NFDRS: Class day A-C
Caution: SO Approval
>72
25-29%
16-18mph D

8. Behave Runs:
Flame Lengths
7 ft
ROS 8
Heat Per Unit Area
2694
Fireline Intensity
386 90 38 10 S 8 S
2000 50 60 69
300

13. It is the day of your prescribed burn, what weather information will you need?

16. The End

17. Mixing Height
Wind

19. Transport Winds
Average horizontal wind speed and direction between the surface and the mixing height

20. Mixing Height
The height below which relatively vigorous mixing in the atmosphere is taking place