Fire Weather Updates

Post by Frank Boksa – Journey Forecaster

Fire Weather Season is upon us and a new product will be introduced this year.  I would like to take a moment to remind everyone of the products we have to keep you informed and safe. Our daily fire weather forecast product is the Fire Weather Planning Forecast. This product is issued daily by 6 AM from March 1 through November 15. During peak spring (March 1 through June 1) and fall (September 1 through November 15) seasons this product is issued twice daily by 6 AM and 4 PM. This product is intended for decision support to those responsible for planning prescribed burns and to the general public who plans a legal burn on their property.

The Fire Weather Watch is a public product that the National Weather Service issues. It is not a routine product but whenever our forecasters have a high level of confidence that weather and fuel conditions combine to create a risk of fire danger and rapid fire growth, we will issue this product from 24 to 48 hours in advance of the threat. This product is typically followed by a Red Flag Warning. The criteria we look at is sustained wind speeds at or above 25 mph along with a relative humidity of 25 percent or less and if fuels (grasses and tinder) are sufficiently dry that they will quickly catch fire and/or allow for a fire to spread quickly. In general if a watch is in place, people planning a burn should consider alternative dates.

The Red Flag Warning is a public fire weather warning product that the National Weather Service issues whenever our forecasters expect wind speeds at or above 25 mph in combination with a relative humidity of 25 percent or less and dry fuels within the next 24 hours. This product is a warning to people that it is dangerous to burn and burning is not recommended. During a Red Flag Warning event, decision makers in the fire weather community as well as state and county officials may want to consider burn bans or to begin contingency planning for additional staff to handle fires that could quickly get out of control.

For marginal fire weather conditions the National Weather Service may issue a Special Weather Statement. The intent of this product is to convey to the general public that there is a concern for fire danger and that they should remain alert for possible upgrades to a red flag warning.

New for this year will be a map of Iowa on our website that will display the Grassland Fire Danger Index for all 99 counties in Iowa. The Grassland Fire Danger Index or GFDI map will serve as a quick glance advisory for all to be aware of what the fire danger is for all counties in the state of Iowa. Our goal with this product is to reduce the number of uncontrollable outdoor fires by alerting the public when conditions favor an extreme fire potential. This should not be used as the only tool to become informed of fire danger but it is very useful as a first step. The map of Grassland Fire Danger Index is an indication of rural fire potential throughout the state and will contain five ratings: low, medium, high, very high and extreme. National Weather Service offices serving Iowa will issue a Red Flag Warning for an area exceeding several counties wide where extreme conditions exist as fires are more likely to occur on those days and more likely to grow in size. While the Fire Danger Index does not predict how a fire will behave, it will give an indication of overall fire activity. Please take a look at this map and tell us what you think of it.


We will also run our safety videos on the fire weather page of our website so please check those out as well. For information on the 2013 Annual Operating Plan and to view forecasts and fire weather planning tools, please visit the National Weather Service website at: