Weather File (.WTR)

WARNING: The Weather (.WTR) File has been deprecated with version 6.1. 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.

The Weather (.WTR) File is an optional ASCII text file required to utilize the optional dead fuel moisture model in FlamMap. This is the same format used in the FARSITE fire simulator, so Weather (.WTR) Files are interchangeable between the two applications.

A Weather (.WTR) File contains daily observations on temperature, humidity, and precipitation 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 file must contain data in the space delimited ASCII format specified below. There are a variety of ways to create or edit Weather (.WTR) Files,

• a text editor such as Notepad or WordPad,
• a spreadsheet application and save to a space delimited file,
• the FlamMap Text Editor (accessed with the buttons on the Inputs tab of the "Run:" dialog box),
• Custom Editors for each ASCII text file type are available in FARSITE,
• generate using the Input > Generate from Types (WTR/WND) command in FARSITE,
• generate in FireFamily Plus.

All inputs must be integers. Each column must be space delimited (leave a space between columns). FlamMap allows weather inputs in English or metric units. The units are selected by inserting the word ENGLISH or METRIC as the first line of the Weather (.WTR) File.

Month Day Precip Hour1 Hour2 Temp1 Temp2 Humid1 Humid2 Elevation rt1 rt2

• Precipitation is the daily rain amount specified in hundredths of an inch or millimeters (integer).

• Hour1 corresponds to the hour at which the minimum temperature was recorded (0-2400).

• Hour2 corresponds to the hour at which the maximum temperature was recorded (0-2400).

• Temperatures (Temp1 is minimum; Temp2 is maximum) are in degrees Fahrenheit or Celsius (integer).

• Humidities (Humid1 is maximum; Humid2 is minimum) are in percent, 0 to 99 (integer).

• Elevation is in feet or meters above sea level. NOTE: these units (feet or meters) do not have to be the same as the landscape elevation theme (integer).

• Precipitation Duration is entered with the beginning (rt1) and ending (rt2) times (0-2400) of the daily rain amount. Only one time period per day is allowed.

Example of .WTR File

ENGLISH
8 10 00 600 1500 48 99 94 11 2400
8 11 00 600 1500 46 96 78 14 2400
8 12 07 600 1600 48 90 74 14 2400 1830 2000
8 13 00 600 1500 42 86 86 19 2400

Using the FlamMap Text Editor

The pencil button, found to the right of the Weather File (*.wtr) text box on the Inputs tab of the "Run:" dialog box, opens the Weather (.WTR) File named in the associated text box.

Generating Weather Files in Fire Family Plus

Weather (.WTR) Files can be generated from hourly WIMS data in FireFamily Plus. From the menu bar in FireFamily Plus go to the Weather > Hourly Data Analysis > FarSite Exports command. Make sure you have a FireFamily Plus database that contains hourly observations.