On Saturday, July 8, 2023, heavy rains caused extensive damage in Shimane Prefecture and other western Japanese regions, prompting local authorities to urge approximately 370 000 residents in two cities to evacuate. Landslides and river floods have occurred in Izumo City, disrupting transportation, although vital services remained intact.
Since the onset of the seismic swarm in the Reykjanes Peninsula, on July 4, 2023, more than 8 500 earthquakes have been recorded in the area between Fagradalsfjall and Keilir. While seismic activity in this area is decreasing, deformation data strongly suggests that magma is rising toward the surface.
Shortly before midnight on July 6, 2023, a seismic sequence commenced close to Eldey Island on Reykjanes Ridge, approximately 10 km (6.2 miles) southwest off of Reykjanes Peninsula, Iceland. As a result, the Aviation Color Code was raised to Yellow.
10 days of continuous rainfall caused a large amount of volcanic material, debris and water to move down the slopes of the Semeru volcano on July 7, 2023, leading to destructive overflows and severe damage.
Hailstorms and torrential rain caused widespread flooding and significant damage in Zaragoza, Spain, on July 6, 2023. The extreme weather trapped people in their homes and cars, damaged infrastructure, and severely impacted the region’s agricultural sector.
More than 4 700 earthquakes have been detected in the area between Fagradalsfjall and Keilir, Reykjanes Peninsula, Iceland since the start of seismic swarm on July 4, 2023. Ground deformation (GPS) observations show significant movements, indicating magma propagation in the region where earthquakes are highly concentrated. Magma intrusion is close enough to the Earth’s surface that a volcanic eruption could occur without further escalations in seismic activity or ground deformation.
Nicaragua’s San Cristobal volcano erupted on July 5, 2023, producing pyroclastic flows and huge amounts of ash.
New activity/unrest was reported for 8 volcanoes from June 28 to July 4, 2023. During the same period, ongoing activity was reported for 15 volcanoes.
Seven fatalities were recorded in Lahore, Pakistan’s second-largest city, on Wednesday, July 5, 2023, following record-breaking rainfall that led to severe urban flooding and substantial infrastructure damage across various areas.
The Icelandic Met Office (IMO) issued a special warning due to intense earthquake activity and the increased likelihood of a volcanic eruption on the Reykjanes Peninsula. IMO also warned rockfalls are possible on the Reykjanes Peninsula due to ongoing earthquake activity, particularly close to Lake Kleifarvatn.
