Possibly the largest jökulhlaup
Update at 15:00
At 03:30 GMT today, 1 October, floodwater was detected at Sveinstindur on Skaftá. The rate of discharge increase at Sveinstindur is the highest observed since the station was established in 1971.
From initial observations, the ongoing jökulhlaup could be the largest to have occurred from the Skaftárkatlar cauldrons. At around 10:00 GMT today, floodwater was also detected in Skaftárdalur, where the present discharge is ~400 m³/s and rising quickly; see photos from Búland nearby. At Sveinstindur, the discharge level is in excess of 1,300 m³/s and rising. The jökulhlaup will likely reach maximum discharge in the lower reaches of Skaftárdalur during the early hours of Saturday, 3 October.
Radio contact still exists with the GPS station in the eastern ice-cauldron; the latest measurements show over 66 m of subsidence since 18:00 GMT on 27 September. During the last one to two hours the rate of subsidence has decreased, suggesting that outflow from the cauldron has peaked.
The map below illustrates where floodwater will be routed. For orientation, see map of gauging stations.