A forecasted shift in winds could cause vog from Kilauea’s volcanic eruption to worsen in some areas.
There’s roughly a two-day stretch when trade winds will “let up significantly,” said Jim Andrews, a meteorologist for AccuWeather.
According to AccuWeather, meteorologists expect northeasterly trade winds to ease later this week, with a southeasterly breeze to replace the typical trade winds from today to Friday.
Andrews said under the trade winds, vog typically tracks west and south and wraps around the south end of Mauna Loa before eddying back to the Kona Coast.
In East Hawaii, Andrews said, when the trade winds are light, winds at night can reverse to a westerly direction.
“When that happens, some of the vog may actually travel in a different direction than the trade winds are carrying it, which has mostly been toward the southwest and, to some extent, wrapping up into Kona.”
There might be a window when some of the vog “could sneak up toward Hilo,” Andrews said.
Vanessa Almanza, a meteorologist with the National Weather Service in Honolulu, confirmed the trade winds are going to die down, which will give way to daytime sea breezes, or winds coming from the ocean on shore, and nighttime land breezes, winds going from the land off shore.
“When we are in our trade wind pattern, we have northeast winds that blow the vog off shore consistently,” she said. “It doesn’t affect too many areas.”
Almanza, however, said when the trade winds calm, breezes from the sea to land will spread the vog inland during the day, while winds at night will shift that vog off shore.
The vog can go northward if there’s a southeast breeze, but “the extent of how far it will go and how concentrated it will be is uncertain as far as these slight wind patterns.”
Regardless, Almanza said the whole island will be affected.
“Hilo’s going to see it, and other areas that don’t see it during the trade winds will see vog,” she said.
The shifting winds also could carry vog to other parts of the state, according to AccuWeather.
In an announcement Wednesday, the state Department of Health said vog conditions and the presence of sulfur dioxide in the air might increase and fluctuate in various areas of the state.
While the intermittent conditions don’t pose a public health threat in areas beyond the evacuation zone, the DOH said they raised concerns about respiratory health and questions about precautions.
Visit the Hawaii Interagency Vog Information Dashboard at ivhhn.org/vog for up-to-date information about vog and sulfur dioxide from volcanic activity.
Email Stephanie Salmons at ssalmons@hawaiitribune-herald.com.
