According to the National Oceanic and Atmospheric Administration, 2019 was the hottest year ever recorded for Oahu. A separate study from the City and County of Honolulu found the hottest day ever recorded also happened last year. And the trend suggests temperatures will continue to rise.
On Aug. 31, the city's Office of Climate Change, Sustainability and Resiliency performed the first Community Heat Assessment. The study would help city officials identify areas experiencing hotter temperatures.
The study found the maximum heat index in several Oʻahu communities was more than 100℉ -- with Waimalu Plaza Shopping Center recording the highest temperature at 107.3℉.
Other areas experiencing hot temperatures included: Ala Moana, Kahala, Hawaiʻi Kai, Waimānalo, Māʻili, Pearl Ridge and Nānākuli.
According to the National Weather Service, 273 daily temperature records were tied or broken across the state in 2019. One hundred thirty five of those days set new records.
"We are going to be headed to even hotter years. We just broke all the records last year," said Josh Stanbro, Honolulu's chief resilience officer.
"By all indications, that's the new normal. So that's why we have to take action immediately to try to reverse that trend. We have to completely slam on the brakes in terms of burning carbon fuels for our energy source."
During a press conference Wednesday, Mayor Kirk Caldwell told reporters increasing the city's tree canopy will help cool communities. He said there was a 10 degree difference between Ala Moana Shopping Center and Magic Island.
Although the cooling effects of trees will take time, city officials are advising residents to protect themselves from the heat in the meantime, especially children and the elderly.
"The time you need to be most prepared is between 10 a.m. and 3 p.m.," said Jim Howe, city emergency services director. "Every one of our lifeguards here knows that when you're out at the beach, the first place you go is you go for the shade. So you want to stay in the shade, and you want to stay well-hydrated."
Howe advised surfers and stand-up paddleboarders to drink a liter of water before heading out. He also urged residents to not leave children or pets in a locked car on a hot day.
More information about the study can be found at resilientoahu.org.