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Weather Stream File (.WXS)

The Weather Stream (.WXS) File is a ASCII text file required for a FlamMap run or Farsite simulation or to utilize the dead fuel moisture model. This file is the equivalent of the deprecated Weather (.WTR) and Wind (.WND) Files combined. This format also has the advantage of providing the actual periodic temperature and humidity values for the dead fuel moisture model. This becomes important if the max/min values in a Weather (.WTR) File do not follow the typical pattern of afternoon max temperatures and early morning low temperatures.

NOTE: Legacy (saved with FlamMap v6.0 or earlier) projects and archives with Weather (.WTR) and Wind (.WND) files will be automatically converted to a Weather Stream (.WXS) File and loaded into the project. Also Weather (.WTR) and Wind (.WND) Files can be converted to the Weather Stream (.WXS) File format with the Utilities > WND and WTR to WXS command. However, it is recommended to generate a Weather Stream (.WXS) File directly from the source hourly weather data. This will result in a more accurate weather stream.

A Weather Stream (.WXS) File contains periodic, usually hourly, observations on temperature, humidity, precipitation, wind speed, wind direction, and cloud cover that depicts a temporal weather stream. The weather stream greatly oversimplifies actual variation in weather. However, this format is an attempt to limit to a practical level, the amount of weather information for modeling the variation in dead fuel moistures due to topography and shading.

Each Weather Stream (.WXS) File must contain data in the space delimited ASCII format specified below. There are a variety of ways to create or edit Weather Stream (.WXS) Files,

use the Utilities > Get Weather command to create a weather stream,
with the button in FlamMap,
a text editor such as Notepad or WordPad,
a spreadsheet application and save to a space delimited file,
export from FireFamily Plus.

Example of .WXS File

Header lines in the Weather Stream (.WXS) File consist of an attribute name and colon followed by the value,

RAWS_ELEVATION: Elevation is in feet or meters above sea level. These units (feet or meters) do not have to be the same as the landscape elevation theme (integer) but are in the units specified by RAWS_UNITS:,
RAWS_WINDS: an optional informational line added in FireFamilyPlus exports,
RAWS_UNITS: the wind speed (mph or km/h), temperature (F° or C°), and precipitation (inches or mm) units are selected by inserting the word ENGLISH or METRIC. North American METAR/ASOS/AWOS (airport) observations and NDFD/RTMA/UTMA forecast products have wind speeds in kts/hour@10 meters. For fire behavior purposes this is equivalent to mph@20 feet.

Column name row is optional. All inputs must be integers. Each column must be space delimited (leave a space between columns).

Column Name	Description
Year	year of the observation
Mth	month of the observation
Day	day of the observation
Time	time of the observation, 0-2359, to the nearest minute (integer)
Temp	temperature at observation time in degrees Fahrenheit or Celsius (integer)
RH	relative humidity at observation time in percent, 0 to 99 (integer)
HrlyPcp	precipitation amount for the time period specified in either inches or millimeters (up to a thousandth)
WindSpd	wind speed at observation time, either the 20ft wind speed specified in miles per hour or the 10m wind speed in kilometers per hour (integer)
WindDir	direction the wind is from at observation time in degrees, clockwise from north (0-360), (integer)
CloudCov	cloud cover specified as a percentage, 0 to 100 (integer)

Using the WXS File Editor

The Weather Stream Editor is available for both FlamMap runs and Farsite simulations. There are minor variations in the editor depending on it's use, mainly including burning periods for Farsite simulations.

The Weather Stream Editor is accessed with the WXS File button. button and selecting one of the options,

Open Existing Weather Stream File

Selecting the Open WXS File... option displays a standard Window's "Open" dialog. Navigate to the appropriate folder and select the desired Weather Stream (.WXS) File. The Weather Stream Editor opens displaying the loaded Weather Stream (.WXS) File for inspection.

Edit WXS dialog after opening a WXS file.

FlamMap run version of Weather Stream Editor

By default the Conditioning Start Date: is set to the first observation in the Weather Stream (.WXS) File, for FlamMap runs the default Conditioning End Date: is the last observation. These dates can be changed with the Weather Stream Editor text boxes or in the "Run" dialog after closing the Weather Stream Editor. If any changes are made to the Weather Stream, conditioning dates, or burn periods make sure to use the Save and Close button. button to save the modifications.

Create a New Weather Stream File

Selecting the Create WXS File... option opens a dialog to create records (observations) for a new Weather Stream (.WXS) File.

Create new WXS file dialog.

Up to 24 consecutive observations can be created. Clicking the OK button displays the new records in the Weather Stream Editor where you can add weather data. Additional observations can be added with the Records button. button. Don't forget to add an elevation to the Elevation: text box, this important when using the dead fuel conditioning feature.

Editing an Existing Weather Stream File

Once a Weather Stream (.WXS) File is loaded, the Weather Stream Editor will allow you to modify that stream. Selecting the Edit WXS File option opens the Weather Stream Editor.

Weather stream editor showing end of conditioning period and edit of preciptation field.

FlamMap run version of Weather Stream Editor displaying end of conditioning period.

The Date field cannot be edited. Units, Elevation, and Conditioning Start/End are modified with the appropriate text boxes at the top of the editor. You can modify existing observations in two ways,

by double clicking in any of the observation fields to modify a single value,
or by clicking the button to open the "Edit Wxs Values" dialog.

NOTE: Changing the Units: list box does not convert the values in the loaded Weather Stream (.WXS) File, only the column headers. Users are responsible for adjusting the wind speed, precipitation, or temperature values when switching between metric and English units. The "Edit Wxs Values" dialog is a handy tool for converting units in the Weather Stream (.WXS) File.

You can load a new Weather Stream (.WXS) File into the editor with the Open File button, the new file will be loaded into the current run or simulation dialog box when you exit the editor.

The Save As button opens a "Save As" dialog where you can save the current observations as a new Weather Stream (.WXS) File.

NOTE: Conditioning information and Farsite burn periods are not saved to this file.

The Inspector button will check the current edits for validity.

The Help button will bring you to the Using the Weather Stream Editor heading above in this online help system.

If any changes are made with the editor you will be asked if you want to save these changes when you exit the editor by clicking the Close button.

Edit Wxs Values Dialog

The "Edit Wxs Values" dialog allows mass edits to be made for a selection of observations or even the entire weather stream. The "Edit Wxs Values" dialog is accessed by clicking the Edit Wx button. button at the top right of the Weather Stream Editor.

Blank Edit Wxs Values dialog.

To edit selected rows in the weather stream, first select the rows in the Weather Stream Editor before opening the "Edit Wxs Values" dialog.

Developing an edit statement consists of several steps,

identify the Target Variable: (a column in the weather stream),
select how to modify the target variable, either replacing with a Constant or changing existing values with an Expression,
add an optional condition to limit the changes to certain records in the selected range.

A simple edit statement might look like this example.

Example of developing an edit statement using the Edit Wxs Values dialog.

Adding or Removing Records

Additional records/observations can be added. However, there is a limit of only one record per hour. Clicking the Records button. button (in the lower left corner of the Weather Stream Editor) displays several options.

Append Record - Adds a single record/observation to the end of the weather stream, either a blank or a copy of the current last observation.
Append Day - Adds all the records/observations of the current last day to the end of the weather stream, either blank records or a copy of that days weather fields.
Insert Record - If there is a skipped or missing hour in the weather stream a new blank observation can be inserted in that position.
Delete Record - Obviously this deletes the currently selected records from the weather stream.

Make sure to use the Save and Close button. button to save the modifications to the current loaded Weather Stream (.WXS) File or the Save As button to save the modified records as a new Weather Stream (.WXS) File.

Setting Burn Periods

The Weather Stream Editor can also be used to set and visualize Burn Periods used in a Farsite Simulation.

Farsite WXS editor showing two burn periods.

Simply select the check box in the Burn field for each observation to be included in a burn period. Don't forget to use the Save and Close button. button to include the burn periods in your simulation.

Graphing the weather stream also displays the burn periods.

Weather Stream Graph

A graph of the weather stream can be viewed by clicking the Graph Wx button. button.

Weather graph example showing conditioning start and Farsite burn periods.

This can be helpful in identifying bad data or just understanding the weather patterns in the weather stream.