Fire weather products fire indices 1 LAPS Fire

Fire weather products, fire indices: 1. LAPS Fire weather index; 2. HAH (High Level Haines Index); 3. HAM (Mid Level Haines Index); 4. FWI (Fosberg Fireweather Index); 5. VNT (Ventilation Index); 6. CWI (Critical Fire Weather Index); Contribution from Steve Albers, Isidora Jankov, Zoltan Toth

Fire weather index 4<wsd< 8<wsd<12 12<wsd<15 15<wsd<18 18<wsd<21 21<wsd<24 Wsp>24 8 50%<RH<60% 8 9 10 11 12 13 14 41%<RH<50% 33%<RH<41% 25%<RH<33% 17%<RH<25% 9%<RH<17% RH<9% 9 10 11 12 13 14 15 16 17 18 13 14 15 16 17 18 19 20 Wsp: wind speed in mph. Note that temperature and soil moisture also counted in fire index calculations. The above is done under extreme dry and hot conditions with soil moisture about 20 %, and temperature warmer than 95 F

An example of LAPS fire weather index LAPS analysis at 1 km, 15 min resolution Based on the surface RH, wind, and temperature, ranging from 0 to 20. (Snow cover, elevation, and land fraction are given secondary consideration.

LAPS Fire Weather Index from 5 km resolution WRF output WRF-ARW 12 hr forecast initialized at 29 Oct. 12 UTC Future generation of Fire Weather Index will be improved by including land use, soil moisture and fuels.

LAPS Fire Weather Index Ensemble mean