About Lightning Probability Index

Lightning Probability Index

The Lightning Probability Index (LPI) is defined as the probability of 10 or more lightning strikes for the day for a 40 km X 40 km grid box. The values are in percent (0% to 100%) for each day. Isolines represent values of 20%, 60% and 80%.

The time periods for the LPI are 18 to 06 UTC (Day 1); 06 to 06 UTC (Day2); 06 to 06 UTC (Day 3) and 06 to 03 UTC (Day 4).

The lightning probability is provided with Dryness Values and alone on a graphic to allow better depiction of the probability distribution.

Lightning will typically occur during the afternoon and evening between 1200 and 2400 hours, but may occur in the overnight and morning hours.

The forecasts are based on numerical weather models and research by Dr. Phillip Bothwell of NOAA's Storm Prediction Center in Norman, Oklahoma. Further information may be found at the link below:

Predicting the Location and Intensity of Lightning Using an Experimental Automated Statistical Method (648 KB PDF Document)