by Loren G. Edelstein | May 16, 2018
Ash-spewing explosions intensified on Hawaii's Kilauea volcano yesterday, prompting a red alert for aircraft flying over the area. An update issued Tuesday afternoon by the U.S. Geological Survey provided the following information:
Current volcanic activity:  
Eruption of ash from the Overlook vent within Halemaumau crater at Kilauea Volcano's summit has generally increased in intensity. Ash has been rising nearly continuously from the vent and drifting downwind to the southwest. Ashfall and vog (volcanic air pollution) have been reported in Pahala, about 18 miles downwind. National Weather Service radar and pilot reports indicate the top of the ash cloud is as high as 10,000 to 12,000 feet above sea level, but this may be expected to vary depending on the vigor of activity and wind conditions.
Ash emission from the Kilauea summit vent will likely be variable with periods of increased and decreased intensity depending on the occurrence of rockfalls into the vent and other changes within the vent. At any time, activity may become more explosive, increasing the intensity of ash production and producing ballistic projectiles near the vent.
Hazard analysis: 
The ash cloud is drifting downwind primarily to the southwest with the Trade Winds. Wind conditions are expected to change in the next 24 hours and other areas around Kilauea's summit are likely to receive ash fall. Ash fall has been reported in the community of Pahala, at locations along Highway 11 from Pahala to Volcano, and in the Ka'u Desert section of Hawaii Volcanoes National Park. 

Ballistic projectiles may be produced should steam-driven explosions occur. Impacts will be limited to an area around Halemaumau. 
[Volcanic gas] Vog or volcanic air pollution produced by volcanic gas has been reported in Pahala. 

The volcanic activity, which began nearly two weeks ago, already has cost Hawaii's tourism industry at least $5 million, as would-be travelers cancel their plans.
Nearly 20 fissures have opened, releasing toxic gases, and officials worry that the volcano may soon blow its top with a massive steam eruption that would shoot boulders and ash miles into the sky.