Known as the Aloha State for its welcoming tropical trade winds, sunny beaches, and spectacular sunsets, Hawaii is facing a fierce battle with Old Man Winter: A powerful storm known as Kona Low will bring heavy rainfall and winds to Hawaii. At the higher elevations on the Big Island of Hawaii, 2 to 4 feet of snow could fall. Combined with 60 mph winds, epic blizzard conditions could develop there.
Deep tropical moisture will flow over the island chain for the next several days, dumping torrential rains that could cause flooding across the state. Due to that flood threat, the National Weather Service has issued a flood watch for all of Hawaii. With temperatures near or below freezing at the Big Island’s higher elevations, precipitation will fall in the form of heavy snow. Additionally, gusty winds will produce swirling and swirling snow, as well as near zero visibility at times. Because of those dangers, the National Weather Service in Honolulu also issued a Winter Storm Warning for Big Island Summits, where 2 to 4 feet of snow is forecast. A Winter Storm Warning is issued any time the National Weather Service believes a significant amount of snow, sleet, and/or ice is expected or is occurring.
According to the National Weather Service, travel could be very difficult or impossible. Blowing snow will significantly reduce visibility at times, with periods of zero visibility. The Honolulu office of the National Weather Service warns: “This will make travel very dangerous or impossible. Any travel plans to the summits should be postponed until the threat abates.”
Mauna Kea rangers have already closed off the access road leading to the summit on the island of Hawaii. “The Mauna Kea Access Road is closed to the public at the 9,200-foot Visitor Information Station due to fog, ice, freezing temperatures, convection, and snow. Rangers will continue to review the road and weather conditions and will reopen the road when conditions are safe,” the rangers said in a statement released today. They will typically close the road whenever there is ice or snow on the road, winds greater than 55 mph for more than 1 hour, and gusts greater than 65 mph are expected, or when less visibility is or is expected to occur of 50 feet. soon.
While most people don’t associate the tropical paradise Hawaii is known for with snow, they are surprised to learn that it snows in winter due to the elevation of volcanic peaks on the islands of Hawaii and Maui. Mauna Kea is the tallest of the bunch at 13,803 feet. Maui’s Haleakala is much lower at 10,023 feet. Because of that difference, the island of Hawaii will see snow more frequently than the lower island of Maui. Just one storm in January 2020 dropped 2-3 feet of snow on the island of Hawaii and created much deeper snowdrifts. Another storm in January 2021 brought dozens of snowboarders and skiers to the mountain. A blizzard hit the Big Island last December, ensuring a white Christmas there for 2022 just 2 months ago.
The Kona Low gets its name from the change in wind direction that occurs when a storm like today’s moves over the Hawaiian Islands. Hawaii is dominated by trade winds that normally blow from the northeast. However, counterclockwise flow around a Kona low located west of Hawaii results in southwesterly winds over the islands, which is generally the leeward or “Kona” side. Kona Lows are most common between October and April. These types of storms draw abundant moisture from the warm tropical waters that surround Hawaii; when this wet flow interacts with the steep topography of the islands that helps remove moisture, extremely heavy precipitation can fall. Because the wind flow around Kona Low is atypical, torrential rains occur in places that are not normally inundated with tropical downpours impacting the islands from time to time.
While the highest mountains will see exceptionally heavy snowfall, even the resorts on the coast will see torrential rain and gusty winds.
According to the National Weather Service, significant flooding due to overflowing streams and drains can occur throughout the state. Roads may also be closed, along with property damage in urban or low-lying locations due to runoff. Landslides can also occur in areas with steep terrain. Areas of particular concern include the eastern and southeastern sections of the Big Island, where road washout could isolate communities.
Widespread heavy rain and even a few thunderstorms are possible, with heavy rain beginning over the Big Island later today and then spreading to the smaller islands tonight. High rainfall rates over an extended period of time could lead to flash flooding, particularly in areas that are already saturated from recent rains. In a statement released to the public, the Honolulu-based office of the National Weather Service said: “A flood watch means conditions are favorable for flash flooding. Flash floods are DANGEROUS TO LIFE. Do not cross fast-flowing water in your vehicle or on foot.”
This will be a prolonged winter storm that should persist in Hawaii at least through Saturday afternoon.
