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Running a Near-Term Fire Behavior Analysis (NTFB)

This fire behavior model produces outputs that represent modeled growth in the form of a 'fire progression' (similar to the FARSITE desktop model). Unlike Short-Term Fire Behavior, NTFB models fire behavior using inputs for weather and wind that change over the duration of the simulation. Though NTFB can model fire growth for up to seven days, it is generally most appropriate for the 'near term' of one to three days (due to unknowns in the forecast beyond that time frame).

The model retrieves forecasted weather and winds for the selected time, using National Weather Service (NWS) Forecast Data for current simulations. For historic fires, the model can use historic weather. 

The Fire Behavior Specialist can accept the fuel moisture, weather, and wind inputs, or can replace those values as needed. Within a short period of time (usually within a couple of minutes), WFDSS NTFB fire spread results are ready for viewing. 

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Last updated on 6/25/2019 1:33:22 PM.

Recommendations for using NTFB

NTFB works a bit differently from the FARSITE that you are used to. FARSITE required a lot of time to build the data for the run, and consequently, was primarily used with medium, emerging incidents or established large fires. With NTFB, you can quickly produce model outputs for making decisions on new fires. However, if the fire is smaller than the resolution used by the model, you might see little or no fire spread (e.g., a 1/4-acre fire is smaller than a single cell on a 30-meter landscape). While these minimal model outputs could be realistic since live fire does require some momentum and time before it spreads, they often under-predict the fire growth. The modeled world is more homogenous than the real world so, if the growth of very small fires is being underpredicted by NTFB, it may be necessary to increase the fire size and capture a few more cells to represent the diversity in the fuels.

To get more realistic outputs, consider increasing the size of your ignition to at least 8 landscape cells (about 2 acres with a 30-meter landscape or around 7 acres at 60 meters) under the following conditions:

While 8 cells might be larger than your actual ignition, the effect of using a larger ignition size washes out over the course of the run and might return more realistic outputs.

In addition, it is important to remember that NTFB does not account for suppression action, an assumption that is particularly important when interpreting NTFB outputs for small fires.

CAUTION: Changing the analysis date, RAWS station, or burn period information, automatically repopulates the hourly records and overwrites your changes.

To run a NTFB:

  1. From the Incident list, select the incident for which you want to run NTFB.
  2. Click View Analyses. The Analysis List appears for the selected incident.
  3. Under New Analysis, select Near-Term, then click Create Analysis for Incident. The New Near-Term Analysis page appears.
  4. Enter an Analysis Name. The analysis name cannot contain an apostrophe or backslash; the cursor blinks if you try to add these characters and a message displays that these characters are disabled.

    Since incidents can have many analyses associated with them, be specific in your name (up to 48 characters).

  5. Set the conditioning days, spotting probability, and crown fire method. There is generally no need to change the spotting seed.
  6. Set the spot ignition delay and foliar moisture content.
  7. Set the start and end dates.
    • For dates in the future, WFDSS uses forecast data.
    • For dates in the past, WFDSS uses historic RAWS data.
  8. Upload ignition and barriers shapefiles. An ignition file is required; barriers are optional. If no ignition file exists, you can create it later (See Creating an Analysis Ignition File).
  9. Verify the RAWS station information.
  10. Click Create. The Detailed Near-Term Fire Behavior page appears. You can modify any information that was added in steps 4 - 9 here.
  11. Verify the following items:
  12. Click Save after making edits and before leaving the Near-Term Information Page.
  13. Create a landscape file and edit it if necessary. (See Creating the Landscape File and Editing a Landscape File.)
  14. Use the Requirements fly-out menu on the right to ensure all required components are completed.
  15. Click Run Near-Term Fire Behavior.The analysis runs. Depending on the parameters you selected, the analysis could take several minutes to complete.

Depending on the landscape size and resolution, as well as the traffic on the server, the analysis could take several minutes to run. Refresh your browser to see the status change to Complete, then select the analysis and click View Results to see the analysis on the map view.

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Last updated on 6/25/2019 1:33:22 PM.

In This Section

Analysis for Fire Behavior Specialists

To run an NTFB:

See Also

Viewing Fire Behavior Request Details

Accepting or Refusing an Analysis Request

Granting Analysis Privileges

Downloading a RAWS KMZ File

Analysis Notes

About Analysis Shape Files (STFB, NTFB, FSPro)

Drawing a Landscape Extent

Creating a Landscape Editor Rule

Importing Landscape Editor Rules

Creating the Landscape File

Downloading an LCP File

Editing the Landscape File

Modifying Landscape File Parameters

Viewing the Landscape for an Analysis

Generating a Landscape Critique

Downloading a Landscape Critique

Basic Fire Behavior (BFB)

Running a Basic Fire Behavior (BFB) Analysis

Copying an Existing Basic Fire Behavior Analysis

Analyst_Assisted Short Term Fire Behavior (STFB)

Running a Short-Term Fire Behavior (STFB) Analysis

Copying an Existing Short-Term Fire Behavior Analysis

Near-Term Fire Behavior (NTFB)

Setting Up Burn Periods for NTFB

Using Gridded Winds (BFB, STFB)

Modifying Wind Information (BFB, STFB)

Modifying Fuel Moistures for Fire Behavior Analysts

About Weather Station Information (BFB & STFB, NTFB, FSPro)

About FWX Weather Files

Downloading FWX Weather Files (FSPro)

Weather Station Availability for Fire Behavior Analysis

Generating Hourly Weather Forecasts

Viewing and Modifying Weather Summary Data (BFB, STFB & NTFB)

Copying an Existing Near-Term Fire Behavior Analysis

Creating an FSPro Analysis

About General FSPro Input Parameters

FSPro Information Menu Option

About Run FSPro Status

Monitoring FSPro Run Status from the Analysis List

About the Date Filter (FSPro)

Copying an Existing FSPro Analysis

About the ERC Stream (FSPro)

About ERC Classes (FSPro)

Setting up FSPro Winds

Editing the FSPro Wind Matrix

Adding or Deleting Rows to the Winds Matrix (FSPro)

Downloading Winds (FSPro)

Recalculating Winds Distribution (FSPro)

Interpreting the Winds Rose (FSPro)

Downloading an Analysis KMZ File

Near Term Fire Behavior Results Downloads

FSPro Fire Behavior Results Downloads

Viewing Analysis Notes

Viewing Analysis Results

Viewing the Analysis Report

Reference

Field Descriptions

Glossary Resources

Spatial Data Reference

Landscape Data Source Reference

Relative Risk Reference

Organization Assessment Reference

Fire Behavior Reference

About the WFDSS Decision Editors