Early Signs Of A Google Search Algorithm Ranking Update On September 23rd

I am seeing signs both in terms of SEO community chatter and the automated tracking tools of another Google search ranking algorithm update. Unlike the last one, where all the tools were spiking but the community chatter was at the same level of the tools, this one seems to have support of both the community and the tracking tools.

The chatter at WebmasterWorld began early this morning and also there is chatter in the Black Hat World forums. Here are some quotes from these forums:

Anyway, I see the sensor tools are spiking somewhat again. SERPS are moving for us a bit, but not that much more than expected.

Seeing some shifts this morning, particularly on mobile.

I'm seeing odd and unrelated results for some queries

Same here. More unrelated and strange than usual, too. Also seeing complaints about Search Console being down.

Big drop in traffic here first after may update lost 70% of traffic didn't manage to recover, now lost again 50-60% of traffic so last 2 days website with 400+ articles in which I invested a lot of money and time is now good for nothing.

Lost 50% of my traffic in the May 5 update (went from average ranking of 2.4 to 5.7 overnight. Down 70% as of last week (average rank if 8.1). In the last 48 hours I've lost additional ranks. Only common denominator I see in my industry (e-commerce, gaming) is every US site getting tanked while foreign (mainly Chinese) sites are getting a huge boost.

Here are screen shots from the various tools, keep in mind, not are all updated yet.

SEMRush:

Cognitive SEO:

RankRanger:

Accuranker:

Algoroo:

The other tools don't seem to be updated as of yet, if there are updates, I'll try to add them later.

Mozcast is now updated:

SERP Metrics as well:

Advanced Web Ranking:

RankRanger showing spikes more now:

Cognitive SEO also:

These new charts were added within 24-hours of posting this story and the chatter is much higher as well.

Do you notice any big shifts this morning in your space? Let us know.

Forum discussion at WebmasterWorld and Black Hat World.

Update: Turns out this was likely related to a now confirmed indexing issue with mobile-indexing and canonicalization.