Commenter Luisport brought this to my attention. Following close to the centnerian celebration of the Katmai and Novarupta large eruption on the june sixth 1912, the volcanoes in question seem to have a slight case of being hungover.
As many of my readers know Novarupta was responsible for the largest eruption during the last 197 years. The eruption of Novarupta was about 30 percent larger than the more famous eruption of Krakatoa.
During the last two days Katmai/Novarupta has been suffering a medium sized swarm of earthquakes ranging from 2 to 3M. The number of earthquakes is not that high, but it is still worthwhile to point it out.
Roughly at the same time as the onset of the earthquake swarm the level of tremor increased sharply for about 14 hours before falling back to back-ground levels.
Katmai/Novarupta is currently coded as a GREEN volcano, as such it is not deemed to be close to an eruption according to USGS/CVO Alaskan Volcano Observatory.
The current increase in activity is interesting, but my guess is that this is not the run up to an eruption. Instead I interpret this as a magmatic emplacement into the volcanic system. Something that could lead to an eruption in the future.
And even if there would be an eruption it would not be on the scale of the 1912 Novarupta eruption due to the magmatic system being severely damaged in the previous eruption. An eruption now would most likely be in the VEI-2 to VEI-3 range.
USGS/AVO-site with webicorder and webcam: