Hurricane Darby rapidly intensified, becoming a major hurricane with maximum sustained winds of 140 mph. The National Hurricane Center’s official forecast puts it closer to the Hawaiian Islands this week, but weakens it as it approaches Aloha State. Meanwhile, what remains of Hurricane Bonnie, which is little more than a lingering blob of moisture moving across the Pacific Ocean, is also expected to hit Hawaii this week, bringing the potential for very strong rains to the state, especially to the Big Island of Hawaii and the island of Maui.
According to the latest advisory from the National Hurricane Center (NHC), Major Hurricane Darby was located at 14.7 N, 125.0 W, which places it in the middle of the Pacific Ocean between Mexico and Hawaii at approximately 1,135 miles west-southwest of the southern tip. of Baja California. The Category 4 hurricane is moving west at 15 mph; the minimum central pressure dropped to 954 mb or 28.17″.
The NHC says Darby will continue its motion today but begin to turn a little more west-northwest tomorrow. Further strengthening is possible and Darby could become a Category 5 hurricane. However, the NHC says peak intensity will likely occur within a day or two, but will then begin to weaken as it moves over colder waters.
Tropical cyclones need many ingredients to maintain their intensity, with warm sea surface temperatures being a very important factor. Given that Darby is expected to move over much colder waters as it continues its west and northwestward journey over the next few days, it is highly likely that the storm will weaken significantly. In fact, the NHC indicates in its latest forecast that Darby will weaken into a post-tropical storm before the end of the week.
While Darby will not approach Hawaii as a full-fledged tropical cyclone, it will still approach as a deep tropical moisture-rich disturbance. And before Darby arrives, what’s left of Bonnie will arrive too.
Bonnie, which was also a hurricane earlier this month, has long since dissipated. However, moisture associated with the former hurricane continues to drift west over the Pacific. This area of increased humidity is expected to interact with the islands on Wednesday and Thursday, with the Big Island of Hawaii and the Maui Islands likely to receive the most precipitation, with windward sections of the Big Island of Hawaii likely to see more. of 5″ of rain over a relatively short period of time. The eastern slopes of Mauna Kea and Mauna Loa, the largest volcanoes on the island of Hawaii, will help extract moisture from the air mass as “It’s sliding west, creating a situation where places like Hilo, Mountain View, Pahala, Volcano and Honomu could see very heavy rain. Heavy downpours could fall on the rest of the islands as well, creating concern across Hawaii not only on flash flood issues, but also on landslides.
It appears at this time that what remains of Darby will be approaching Hawaii next Sunday and/or Monday. As is the case with Bonnie, most precipitation would impact Maui and Hawaii, with the Big Island once again in line to see the most rain.
Although heavy rains can create problems such as flooding, they will also bring some benefits. Hawaii has been exceptionally dry for many months and any rain will be welcome to extinguish farms and forests. Getting a significant amount of rain could be beneficial for the drought, especially if it arrives without the strength of tropical storms or hurricane-force winds of a typical tropical cyclone.