Severe Weather in Idaho

Severe Weather Awareness Week News Releases: Avalanche, Roads in Winter, Wind, 

SEVERE STORMS

Influenced by the Pacific Ocean, Idaho’s moderate climate sees relatively few severe storms in comparison with the rest of the nation. Severe storms constitute the most common type of Presidential Disaster declaration in the United States, although only two storm-related Presidential Disaster declaration were made in Idaho during the period 1976-2000. 

Damaging storms do occur, however, and casualties and extensive property damage (including impairment of economic activity) result throughout the state. Two types of severe storms are of concern in Idaho:

·   Winter storms with accumulations of snow and ice, extreme cold, and reduced visibility.

LIGHTNING

Details on lightning events in Idaho are limited, but basic statistics are available.  National Oceanographic and Atmospheric Agency (NOAA) maps divide Idaho into four bands, showing historic records of 10-19, 20-29, 30-39, 40-49 days of thunderstorms per year, respectively.  The rate increases from the southwest portion of the state to the northeast, with the highest rates centered in the Lemhi Pass area. Lightning casualties and damages peak during the summer months.

Except in cases where significant forest or range fires are ignited, lightning generally does not result in disasters.  For the period 1959-1994, NOAA reported twenty deaths, sixty-seven injuries, and 305 damage reports in Idaho. More recently, fatalities were reported in 1995 (three), 1996, and 1997.  The extent of the damages is unknown and both injuries and damage are likely under-reported, possibly significantly.

 While Idaho experiences thousands of strikes annually, lighting poses a minimal hazard to most individuals. Communication, utilities, and most critical facilities with electronic equipment employ techniques to minimize the impact on their operation.

The general weather patterns of the last several decades are expected to continue.  This will result in a maintenance of spring and summer, afternoon and evening occurrence of lightning through Idaho.  Historical rates of injury are also expected to continue.  The increasing dependence on electronic equipment and its utilization in all aspects of life may lead to an increase in the amount and extent of property damage resulting from lightning strikes.