LAL and Spot Weather Forecast

Lightning Activity Levels

  1. No thunderstorm or building cumulus clouds.
  2. A single or few building cumulus with only occasional one reaching thunderstorm intensity are observed. Thunderstorms or lightning need not be observed for this activity level to be assigned; however at least one large cumulus cloud must be present.
  3. Occasional lightning (an average or 2 to 3 strikes per minute) is observed. Building cumulus is common; thunderstorms are widely scattered.
  4. Frequent and intense lightning (strikes greater than 3 per minute) is observed. Thunderstorms are common and cover 10 to 30 percent of the sky. Lightning is primarily of the cloud-to-cloud type but ground strike lightning may be observed.
  5. Frequent and intense lightning is observed. Thunderstorms are common occasionally obscuring the sky. Moderate to heavy rain may occur with the thunderstorms and light to moderate rains usually precede and follow the lightning activity. Lightning of all kinds is characteristically persistent during the storm period.
  6. A dry lightning situation. Low lightning flash rate (similar to Level 3). Scattered towering clouds with a few thunderstorms. Bases of the clouds are high. Virga is a predominate form of precipitation.

Spot Weather Forecast:

Spot weather forecasts should be requested for fires that have a potential for extreme fire behavior or exceed initial attack or are located in areas for which red flag warnings have been issued.

The basic elements of a Spot Weather Forecast are:

  • Name of fire or other project
  • Fire Character (ground, crown)
  • Control Agency
  • Elevation (top and bottom)
  • Request Time and Date
  • Size
  • Location by ¼ section
  • Exposure
  • Drainage Name

Weather Conditions

  • Place
  • Elevation
  • Observation Time
  • Wind Direction
  • Wind Velocity (eye level or 20 feet)
  • Dry Bulb
  • Wet Bulb