Kona low, What is it and its Impacts to Hawai'i? (Credit: Meteorologist Jessica Olsen)

Image Courtesy: Mauna Kea Weather Center in cooperation with the University of Hawaii Department of Meteorology

DISCUSSION: Winter is in full swing in the Northern Hemisphere, and while much of the United States mainland is experiencing cold temperatures, or winter storms which encompass snow, there are warm locations within the U.S. that are experiencing winter phenomena not known to its mainland counterparts. Hawaii, the 50th state, experiences 11 of the world’s 13 climate zones, often experiencing various weather on several parts of one island even within several miles. Of notable recent winter conditions in Hawaii, was the widespread impacts of a Kona low.
 
As recent as the week of February 9th, 2019, did the state of Hawaii feel the effects of a Kona low in the area. Typically, island weather is dominated by the Northeast trade wind flow, at times bringing wet conditions to windward and mauka (mountain) locations of the island chain. A Kona low, Kona in the Hawaiian language having various interpretations, in this context could be determined as “leeward or dry side of the island,” is primarily a subtropical cyclone (counterclockwise inward flow) with a southerly wind component in this case. Often Kona lows bring unprecedented winds, large surf, heavy rains, and other hazardous conditions to the islands. During this most recent storm, surf brought nearly 30-40-foot faces, winds in excess of 45 mph and of note a 191-mph wind reading at the top of Mauna Kea, in addition to snow seen on Mauna Kea, Mauna Loa (on Hawai’i) and Haleakala on Maui, an astounding happenstance on Maui as elevations of snowfall around 6000 feet.
 
Kona lows while they often disturb the trade wind flow, bringing cooler temperatures, are not uncommon outside of summer, often seen between fall and spring in the Pacific. There is a potential for the low to be subtropical or tropical, often a colder core of air than a tropical storm, mass disorganizations and in general characteristics of several types of systems. While winter is not quite over yet for the islands, chances so see such storms may decrease as temperatures begin to warm waters and the atmosphere in the Pacific region, as we move into spring and summer seasons.

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© 2019 Meteorologist Jessica Olsen

​Video: Honolulu, Hawai'i, Courtesy: Meteorologist Jessica Olsen