WILDFIRE: LATEST LEARNINGS- v01.6

WILDFIRE: LATEST LEARNINGS

[Home] [Index] [News]

[Previous] [Next] Click to view: [General content] ...then... [Operational content] ...then... [Expert content]

[Posters]
[Science]

.
General learning outcome:

SPECIFIC HIGH COUNTRY WEATHER:

Specific learning outcome:

Foehn winds are important in southeast Australia.

Topic:

The impact of a foehn wind on surface fire weather.

Expert Awareness for Advanced Firefighters & Fire Behaviour Analysts


The two types of foehn wind will only form when the winds are aligned across the ridge. At a site downwind, there may be a sudden onset of foehn conditions as winds back ahead of an approaching cold front.
This increase may happen within the normal interval specified for taking fire ground weather observations. Thus when foehn winds may occur, the weather observation interval must not exceed 30 minutes.
For prediction work three tasks must be considered.
Firstly the general isobarically-driven winds need to be determined, from the MSLP chart, to see if they may be aligned normal to the terrain.
Secondly the ability of wind shifts to take the situation into or out of foehn conditions. Guidance on wind direction variability may be sought from Pasquill’s Index.
Thirdly consideration may be given to issuing watchouts or Red Flag Warnings (Foehn wind).
.
This website is dedicated to bringing forward the latest research findings. They are provided to allow firefighters to be made aware of critical safety issues ahead of the material being included in the national training curriculum.
Material prepared by Rick McRae for AFAC Research Dissemination Pilot Study, March 2012.