Meteorologist at Weather Underground, background in fire weather research. Twitter: @WunderKari
By: Kari Kiefer , 5:28 PM GMT on September 28, 2012
We have launched our new Fire Page. You can find it at http://www.wunderground.com/fire. Or go to the Severe tab from the home page and select Fire Weather. The page features a map with various fire layers and tools for predicting fire spread.
The newest map layer is Fire(inciweb), which incorporates data from The Incident Information System (Inciweb). Inciweb is an inter-agency information management system created to provide the public of incident related information. In other words, its a one-stop shop for fire information for the US. By clicking on the fire hat icon in the center of the fire perimeter, the fire information loads below the map. This table loads detailed information on the fire, such as overview, cause, date of origin, current size. percent contained, estimated date of containment. Some fires will have additional details like fuels burned, fire behavior, significant events (which includes road closures and evacuations), planned actions, and sometimes more.
As of September 28th, 2012, the Mustang Complex Fire in Idaho the largest wildfire in the US, at 338,787 acres. You can view the inciweb fire information by turning on the Fire(inciweb) layer and zooming into Idaho.
If you want to do some fire spread forecasting of your own, you can turn on the weather stations layer and see what the winds are doing. If the winds are predominantly from the north, you can assume the fire will propagate to the south, as well as the smoke plume. However, the fuels (or vegetation type) play a big role in which direction the fire will spread. You can turn on the Fire(risk) layer to determine the Fire Danger Rating nearby the fire. The fire has a higher chance of spreading in areas of high fire danger because the model takes into account the current and previous weather conditions, vegetation types and fuel moisture content. This is a nice general fire danger scale. There are additional options on this layer to display such as the Haines Index (which takes into account atmospheric stability), the Keetch-Byram Drought Index (which involves soil and ground moisture), and the 10-hour, 100-hour, and 1,000-hour Dead Fuel Moistures. These are a bit tricky to understand. Consider small vegetation of 0.25 to 1.0 inch in diameter. These are the smallest needles and shrubs, and since they are so thin, they are able to dry out the quickest and called the 10 hour Dead Fuel Moisture Content. The thicker branches and logs that are 3 to 8 inches in diameter take the longest to dry out, and are called 1,000 hour Dead Fuel Moisture Content.
For the Mustang Complex Fire, the wind is currently taking the smoke plume northward, but the fire danger to the north of the fire is green, or low. This implies that the danger isn't high. However, I would still be worried if I were north of the fire because the 1,000 hour Dead Fuel Moisture is dry around the fire, and fire spread is likely. Complex terrain also allows for rapid fire spread for two reasons: 1) It is difficult to get fire personnel to the fire to manage and contain it and 2) When fires are in canyons and valleys, the vegetation ignites more readily on the adjacent side because it has been preheated by the flames.
Check the fire page often to keep updated on wildfires across the nation!
The views of the author are his/her own and do not necessarily represent the position of The Weather Company or its parent, IBM.