(BIVN) – During a Tuesday conference call, scientists with the United States Geological Survey and the National Oceanic and Atmospheric Administration detailed the eruptive activity occurring at two locations on Kilauea volcano.

Fissure number 20 opened on the lower East Rift Zone this morning in the Lanipuna Gardens subdivision northeast of fissure 19

Most of the activity remains concentrated at fissure 17, although lava flows have advanced little over the past day. “An estimate of advance rate overnight was about 20 yards per hour,” the USGS Hawaiian Volcano Observatory reported this morning. “The flow is moving generally east south east and as of this morning was about 1.2 miles above Highway 137.”

Meanwhile, at the summit, ash emission from the Overlook crater within Halemaʻumaʻu has increased this morning compared to previous days.

“Although varying in intensity, at times the plume contains enough ash to be gray in color,” USGS reported. “The cloud is rising an estimated 3 to 4,000 feet above the ground, but altitudes are varying with pulses of emission. The ash cloud is drifting generally west and southwest from the Kilauea summit and ashfall is occurring in the Kaʻu Desert. Communities downwind are likely to receive ashfall today and should take necessary precautions.”

During the call, USGS Hawaiian Volcano Observatory scientist Steve Brantley talked about the activity going on in the two different locations. Also on the call: David Damby, a USGS research chemist, and John Bravender with the NOAA National Weather Service.