Icelandic Met Office has issued a warning about increased risk of glacier flood from Múlakvísl that comes from Mýrdalsjökull glacier (the glacier on top of Katla volcano). Upon checking reports about increased smell and detecting higher conductivity on sensors, police in the area have confirmed with Icelandic Met Office that unusual high amount of water is in the river at the moment.
Currently conductivity in Múlakvísl is 290μS/cm and is stable at the moment. This suggest that a cauldron is about to empty it self of melt water and resulting in a glacier flood.
It is possible to monitor conditions in Múlakvísl here on Icelandic Met Office website.
I will update this article as needed.