Increased potential for an eruption at Kīlauea’s middle East Rift Zone prompts rise in alert level to WATCH

The intrusion of magma that began on Saturday in Kīlauea’s middle East Rift Zone, continues, increasing the potential of an eruption in this region. Accordingly, the USGS Hawaiian Volcano Observatory is raising the Volcano Alert Level for ground-based hazards from ADVISORY to WATCH and the Aviation Color Code from YELLOW to ORANGE.    

Current activity is taking place in a remote area of Kīlauea’s middle East Rift Zone, within Hawaiʻi Volcanoes National Park. No changes have been detected in the lower East Rift Zone, or Southwest Rift Zone.  

Intense and localized earthquakes between Maunaulu and Makaopuhi Crater, accompanied by ground deformation patterns indicative of underground crack growth began at approximately 6 p.m. HST on Sept. 14, 2024. While the intensity of earthquake activity has decreased, continued ground deformation changes show that magma is still moving beneath the ground from summit storage chambers to the area between Maunaulu and  Makaopuhi Crater. An InSAR image showing recent ground extension between Maunaulu and Makaopuhi Crater is available here:

Starting around 9 p.m. and continuing until 10 p.m. HST Sunday evening, infrasound instruments detected a strong signal typical of gas or steam venting and seismometers in the middle East Rift Zone are recording weak, sustained low frequency tremor. However, HVO’s webcam network has not shown any evidence of eruptive activity and GOES satellite data do not show any thermal anomalies at the time.Strong rainfall in the area was complicating interpretation. In 2007, an intrusion in this area erupted a very small pad of lava approximately the size of half a football field, so it is possible a similarly small eruption could take place without detection in these conditions. 

Numerous eruptions took place in this area during the 1960s–1970s, most of which lasted less than one day to about two weeks. Long-lived eruptions took place at Maunaulu (1969–1971 and 1972–1974) and Puʻuʻōʻō (1983–2018). The most recent eruption in this area took place over 35 years at and near the Puʻuʻōʻō vent. The location of any future outbreak will determine what areas could be in the path of new lava flows. A map of past eruptive activity in the upper-to-middle East Rift Zone of Kīlauea is available below.

HVO will continue to monitor this activity closely and adjust the alert level/aviation color code for Kīlauea accordingly. Should volcanic activity change significantly, a new Volcanic Activity Notice will be issued.