The Application of Southwest Monsoon Data and Forecasts to Wildland Fire Management

1. Program for Climate, Ecosystem and Fire Applications The Application of Southwest Monsoon Data and Forecasts to Wildland Fire Management Timothy Brown CEFA, Desert Research Institute Gregg Garfin CLIMAS, University of Arizona 21 Apr 2004

2. Fire Management Perspective • Suppression resources • Monsoon does not necessarily reduce number of fires… • but likely reduces fire behavior severity (i.e., large fires) • Prescribed fire • Intentionally lit fires to meet a planned management objective • Prescribed natural fire use • Use of natural started fire to meet a planned management objective

3. AZ/NM Fire Occurrence

4. USDA-FS The Southwest Monsoon and Wildland Fire • Changes in atmospheric conditions stemming from the monsoon result in both fire producing and fire mitigating effects

5. Human- and Lightning-Caused Fires in the Southwest Monsoon Region

6. Key Monsoon-Fire Physical Elements • Relative humidity • Wet versus dry thunderstorms • precipitation

7. Key Monsoon-Fire Attributes • Onset date • Strength • magnitude of RH • number of wet T-storms • Intraseasonal consistency • no long dry periods

8. Monsoon Forecast Uses for Fire Management • Temperature, RH, wind speed • Rx fire prescription parameters • Fire danger calculations • Wet/dry thunderstorms • Ignition potential • Suppression resource demands • Fire crew safety • Precipitation • Fire danger calculations • Ignition potential

9. Relevance to Fire Weather Meteorologist • Provide fire weather watches and red flag warnings • Firefighter safety • Tactical planning • Provide value added information • Fire danger • Fire behavior • Fire potential • Provide medium-range forecasts • Strategic planning

10. Monsoon Research Issues of Interest to Fire Agencies • Improving seasonal and medium-range forecasts of onset • Assessing accuracy of GFS RH forecasts • Perception: RH values typically too high during monsoon season • Improving ability to predict strength and consistency of monsoon • Improving ability to predict wet versus dry thunderstorms

11. Monsoon Research Issues of Interest to Fire Agencies • What factors lead to monsoon false-start or double onsets? • What atmospheric patterns should be utilized for monsoon monitoring and prediction?

12. Monsoon Research Issues of Interest to Fire Agencies • Establishing monsoon definition relevant to fire management • Current dew point definition is not applicable • Could be function of atmospheric circulation or a meteorological variable, but… • Might better be a fire danger or fire potential index – closely linked to fire business • Cost • Resources • Management actions

13. Timber fuel prescription matrix - Zone 2 Day 1 forecast RH 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 T 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 WS 05 06 07 08 09 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 1000-FM 05 06 07 08 09 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 BI 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 Burn assessment FM: 1000 hr time lag fuel moisture BI: Burning index