More lightning facts

Conditions across the Inland Northwest are expected to dry with warm afternoon temperatures this week. However, May is one of the months we will experience thunderstorm activity with lightning. Despite great progress in its understanding and behavior, lightning is still one of the more mysterious natural phenomena.

As I’ve mentioned in previous articles, there are approximately 3 to 8 million lightning flashes across the globe. They can seem quite large when viewing from a distance, but the width of a typical bolt is about an inch. The length can stretch for up to 2-10 miles and the typical duration of a lightning flash is about one-fifth of a second. The typical bolt of lightning is about 40,000 to 50,000 degrees and is about four to five times hotter than the surface of the sun.

Damage costs from lightning are estimated at $4-5 billion each year in the U.S. Lightning also kills approximately 300 million trees each year. Across the Inland Northwest, many of our large fires in the summer and early fall seasons have been caused by dry thunderstorms that were generated from numerous lightning strikes.

About 6 years ago, on April 29, 2020, the World Meteorological Organization, the agency that maintains global records, reported that it confirmed the longest single flash of lightning in recorded history. The event covered an area of approximately 477 miles across Texas, Louisiana and Mississippi. The flash was seen and recorded by satellite and beat the previous record set in Brazil of 440 miles set back in 2018.

The WHO also confirmed a new record for the greatest duration for a single lightning flash. On June 18, 2020, a massive thunderstorm developed over South America in the countries of Uruguay and Argentina. The flash lasted for a whopping 17.102 seconds, beating the previous record of 16.73 seconds from a storm over northern Argentina on March 4, 2019.

Lightning is not limited to the classic cloud-to-ground strike. It can travel between clouds, within a single cloud, or even upward from tall structures. Rare phenomena such as “sprites” and “jets” can extend high above thunderstorms into the upper atmosphere, showing that lightning’s reach will go far beyond what we typically observe.

There are also more unusual and less understood types of lightning. Ball lightning is a rare phenomenon described as a glowing, spherical object that can float or move unpredictably during storms. Photographing this phenomenon is difficult, but there are images on the Internet. Although reported for centuries, scientists are still studying how it forms. Ribbon lightning occurs when strong winds blow successive lightning strokes slightly apart, making a single bolt appear as multiple parallel strands. Forked lightning, the classic branching shape, happens when the electrical path splits into multiple channels as it travels.

Lightning does not occur evenly across the globe. Certain regions experience far more frequent strikes due to their geography and climate. The most lightning-prone place on Earth is Lake Maracaibo, where a phenomenon known as the “Catatumbo Lightning” occurs. This area experiences thunderstorms on over 250 nights per year, with nearly continuous lightning flashing for hours at a time. Warm, moist air from the Caribbean Sea collides with cooler mountain air, creating ideal conditions for storm formation.

In the United States, Florida is often called the “lightning capital” of the country. Its location between the Atlantic Ocean and the Gulf of America (Mexico) creates ideal conditions for afternoon thunderstorms, especially during the summer months. Cities like Tampa and Orlando regularly experience high lightning strike densities each year.

Idaho experiences about 9 to 36 thunderstorm days annually, creating significant risks from lightning, particularly during dry summers. Lightning is a major fire starter, causing 47% of wildfires in Eastern Idaho between 2000 and 2020. The state experiences significant activity often accompanied by heavy, localized, and fast-moving storm cells.

In terms of our local weather, April was a relatively “normal” month in Coeur d’Alene and other parts of the Inland Northwest. Cliff reported an average April high of 59 degrees with a low of 37. Total April precipitation was 1.68 inches, compared to the normal of 1.77 inches. There was no measurable snowfall, but the normal for April is 0.7 inches.

Unless there is a total surprise, snowfall across the lower elevations has ended for the 2025-26 season. Only 32.4 inches was measured at Cliff’s station. For the 2024-25 season, 36.1 inches fell. This two-year total of 68.5 inches is less than the seasonal average of 69.1 inches. Also, with an expected strong, perhaps a monster El Nino later this year, the odds of snowfall for the 2026-27 season across the Inland Northwest are much lower than average. At the Spokane International Airport, total snowfall for the season was 24.8 inches, much lower than the average of 45.3 inches.

The rest of the spring and summer forecasts are expected to be drier and warmer than normal. The long-range models indicate mostly dry conditions with the next chance of rain across the region around the middle of the month. Coeur d’Alene’s normal moisture for May is 2.37 inches.

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Contact Randy Mann at [email protected].