Extreme fire hazards have returned to the islands of Hawaii just weeks after a fire weather event unfolded on August 8 on the islands of Maui and Hawaii, destroying thousands of acres of land, more than 2,000 structures, and claiming more than 115 lives. Atmospheric conditions are ripe to create fire weather conditions today, although winds aren’t forecast to be as severe as they were during the August 8 event.
According to the National Weather Service, “fire weather” is the use of meteorological parameters such as relative humidity, wind speed and direction, mixing heights, and soil moisture to determine whether conditions are favorable for fire growth and smoke dispersion. Based on the analysis by meteorologists at the Honolulu office of the National Weather Service, a Fire Weather Watch, indicating the possibility of fire weather risks, have been issued for for large parts of each island, especially the western/leeward side areas which could be influenced the most by downslope flows.
“The combination of dry fuels, low relative humidity values, and windy trade winds, will result in very high fire danger across leeward sections of the islands today. Any fires that start will likely spread rapidly and be very difficult to control. Outdoor burning should be avoided altogether until these critical conditions end,” the National Weather Service office in Honolulu, Oahu warned with the Red Flag Warning they issued for today.
The Red Flag Warning is in effect for portions of both Maui and Hawaii that saw destructive fires on August 8, as well as leeward portions of Kauai, Oahu, Molokai, and Lanai. The warning is in effect through 6 pm tonight local time (midnight ET.)
A strong high pressure, estimated to be 1030 mb, is centered around 1,200 miles north-northeast of Honolulu and that is responsible for driving strong trade winds across the state from east to west. Trades will ease tonight as the high shifts further north. Due to the windy conditions, the National Weather Service has also issued a Wind Advisory for much of Maui County and the Big Island through 6 pm too. In addition to windy, conditions are also very dry, with minimum humidity of 35-45% expected.
During the August 8 fire weather event, winds gusted above 60 mph; the same won’t be the case today, with trade winds of 20-30 mph expected with occasional gusts of 40-50 mph possible, with the strongest winds expected in the downwind / leeward areas of the higher terrain of the islands of Maui and Hawaii.
Yesterday, Hawaii County Mayor Mitch Roth declared an emergency due to the Red Flag Warning. “Due to the possibility of imminent disaster due to property damage and/or bodily injury to residents of Hawaii Island, and the need for government agencies and representatives from the private sector to mobilize and provide immediate services to our island residents, a Civil Defense state of emergency is authorized,” wrote the Mayor in his proclamation.
With the emergency declaration, Mayor Roth has banned all outdoor burning and all outdoor open flames in the districts of North Kohala, South Kohala, North Kona, South Kona, and Kau through noon on Friday. In addition, Hawaii County Civil Defense announced that all camping permits for Thursday are cancelled for Mahukona, Spencer, Kohanaiki, Punalu`u, and Whittington Beach Parks.
Fires continue to burn on Maui. The most lethal fire there in the town of Lahaina is 90% contained, according to Maui County’s latest update. 2,170 acres burned including much of the town. Up the slopes of Haleakala, the Olinda fire is 85% contained consuming 1,081 acres while the Kula fire is 90% contained, consuming 202 acres including many homes.
On Maui, the Maui Fire Department released tips to people there to reduce the risk of additional fires:
- Refrain from ALL outdoor burning, including cooking
- Avoid the use of mechanized equipment outdoors, including the use of yardwork equipment
- Do not drive your vehicle in dry, tall grass. The underside of your vehicle is hot and can easily ignite grasses from your exhaust muffler
- Ensure trailer chains do not drag on the ground
- Be aware of wind direction and gusts that could spread fire rapidly
- Have an escape route to a clear area safe from rapid-fire spread
According to the Hawaii Wildfire Management Organization, about 0.5% of Hawaii’s total land area burns each year, equal to or greater than the proportion burned of any other US state. Over 98% of wildfires are human caused. Human ignitions coupled with an increasing amount of nonnative, fire-prone grasses and shrubs has made the threat of wildfire worse.
Ahead of another fire weather event in Hawaii, the latest Drought Monitor maps show bad news: the entire state is abnormally dry or worse. Moderate to severe drought conditions co-exist with the current Fire Weather Watch Zone. #HIwx pic.twitter.com/wH3K7YWa82
— the Weatherboy (@theWeatherboy) August 30, 2023
Hawaii is under the influence of a weather pattern tied to El Nino, in which the atmospheric pattern creates unusually dry conditions over the summer and especially the autumn months there. Worsening drought conditions are drying-out tens of thousands of acres of flammable, invasive wild grasses that cover the islands, setting the stage for danger whenever fire weather conditions arrive.