A freak thunderstorm quickly developed off the Pacific coastline near Los Angeles Sunday afternoon and moved onshore at popular Venice Beach in Los Angeles County. Frequent lightning strikes killed one man and injured a dozen others. This may be the only time that a summertime beach lightning fatality has occurred in California history.
Lightning strikes across the U.S. on Sunday July 27th. Note the small cluster of blips in southern California and even off the coast of central California. This was due to the summer monsoonal flow sliding further west than is normal. Lightning flash map from VAISALA’s Lightning Detection Network.
Although summer thunderstorms are common in the Sierra Nevada and desert southeast regions of California during the Southwest summer ‘monsoon’ season of July-September, it is unusual for the monsoonal flow to track further west and over the coastal portions of the state (as occurred on Monday/July 28). When this does occur, climatology dictates that the thunderstorms that do form (when this situation arises) normally impact the coastal hills and the Antelope Valley region of L.A., not the coastside.
Lightning flash density map for the greater Los Angeles region during the monsoon season of July-September. Data from 1987-2000. Map produced by Jamie Meier and Richard Thompson of NWS-Los Ageles from this monograph on the subject.
The lightning death at Venice Beach was only the 33rd to occur in California since 1959. As the map below illustrates, lightning fatalities in California are exceptionally rare given the state’s large population:
Lightning fatalities by state for the period of 1959-2013. Aside from Alaska, Hawaii, and Washington, California has the lowest per-capita fatality rate due to lightning strikes of any state in the U.S. Map derived from NCDC data.
It is interesting to compare the ‘fatalities-by-state’ map with the one above which displays the ‘lightning flash density’ per square mile per year across the U.S. based on the POR of 1997-2010. The reason Florida leads (by far) the number of lightning deaths becomes obvious. Map produced by VAISALA using their proprietary National Lightning Detection Network.
On the rare occasion when there is a lightning fatality in California it almost always occurs in the Sierra Nevada where high mountain hiking, camping, and lake fishing are popular summertime pursuits.
One of the 33 fatal lightning events that occurred in California since 1959 was that which happened in August 1975 when a group of hikers posed on top of Moro Rock in Sequoia National Park as a thunderstorm developed overhead. Lightning struck these two boys a second after this photograph was snapped by their sister. All were seriously injured and another hiker standing just outside the frame was killed. Photo by Mary McQuilken of her brothers Sean (left) and Michael (right).
In spite of yesterday’s fatality, the year 2014 has been close to normal so far as lightning caused fatalities nation-wide to date.
Annual lightning fatalities by gender for the period of 2006-2014 (to-date). Over the years lightning deaths have decreased substantially from an average annual toll of over 100 in the 1950s-1980s to fewer than 50 for this current decade. Greater weather awareness and more accurate storm forecasting can account for this decline. Hopefully, this trend will continue into the future. Table from NOAA.
Christopher C. Burt
Weather Historian
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