A jökulhlaup has started in Múlakvísl, the glacial river that comes
off Mýrdalsjökull, that is the glacier that Katla is under.
No eruption at this point though.
The Icelandic National Broadcasting Service (RUV) has a webcam on
it. Not much to see yet.
http://www.ruv.is/katla
Small earthquakes in a line
across the caldera though.
Some have a depth of less than a km, and are, most likely, just the
ice shifting, but there is steady activity down to 10-15 km depth,
suggesting some magma movement.
Police are warning of strong H2S odour on the sands, and possibly
lethal concentrations of the gas in low lying areas nearby.
The river is rising, not clear when it will peak at this stage,
water conductivity is high, indicative of high concentrations of
ionic salts, and geothermal origin.
PS: holy crap!
This is a snapshot from the water meter upriver - level jumped 5
meters in minutes, the downriver meter by the bridge jumped 3 meter,
then leveled off - probably getting a dam from the bridge floor.
PPS: at 5 am RUV is reporting the bridge across Route 1 at Múlakvísl
is overtopped by the flood, and it does not appear to have peaked.
Route 1 is closed at Mýrdalssandur.