Showers and thunderstorms brewing southeast of the Big Island continue to become more organized, a National Weather Service meteorologist said. A tropical depression could form within 48 hours.
Showers and thunderstorms brewing southeast of the Big Island continue to become more organized, a National Weather Service meteorologist said. A tropical depression could form within 48 hours.
“It’s taking a little longer than expected to actually get organized and develop into a depression, but it still looks like something will happen in the next day or two,” John Bravender, a meteorologist with the National Weather Service in Honolulu, told West Hawaii Today.
Located 670 miles southeast of Hilo as of Thursday morning, the weather system was moving slowly toward the northwest. After showing signs of deterioration as the weather system encountered strong wind shear early Tuesday, the showers and thunderstorms associated with the broad area of low pressure intensified overnight into Wednesday.
“For the past several days, we have been seeing increases in convection at night and a decrease (in convection) during the day, it just pulses up and down,” he said. “Eventually, we expect the convection to be more continuous and it will intensify into a tropical depression.”
Current forecast models show the weather system having a short window to intensify once it reaches depression status. It likely would not get stronger than a tropical storm, which features sustained winds of 39 to 73 mph, Bravender said. Should it reach tropical storm strength, it will be named Niala.
“It looks like this weekend there is going to be a big increase in the amount of shear. If it does spin up into a depression, it has a very short window to develop as it drifts northward,” he said, adding that by the end of the weekend, the tropical cyclone will still be several hundred miles southeast of the island.
Rainfall from the disturbance is not expected to impact the Big Island through the weekend, providing some reprieve to leeward Big Island areas that have seen flooding in recent weeks. However, residents and visitors can still expect heavy showers during afternoon and night hours in leeward areas because of instability and the typical summer weather pattern of onshore sea breezes ascending the mountain slopes and interacting with descending trade winds.
Elsewhere in the Central Pacific, no tropical cyclones are expected to develop through Friday afternoon. The Central Pacific covers an area spanning west of 140 degrees longitude to the international date line. Hawaii falls within this area.
In the Eastern Pacific, forecasters continue to keep tabs on an area of low pressure that is expected to develop several hundred miles south or southwest of the Gulf of Tehuantepac, Mexico. The current forecast has the weather system developing into a tropical depression by the end of the week as it moves toward the coast of Mexico.
The Central and Eastern Pacific hurricane seasons continue through Nov. 30.
Get more hurricane-related content, including preparation tips, evacuation info and daily tropical weather updates, on our hurricane season page, sponsored by Clark Realty, at www.westhawaiitoday.com/hurricane-season-2015.