Truslow
Since your pattern shows precisely a seven day cycle… then let's look at it logically…
What day of the week is it – and is that search term time sensitive in terms of volume?
For example, take the search term "Brunch." Brunch is typically a Sunday thing… so naturally search volume for that term would be much higher on a Sunday (or possibly Saturday when people are planning for tomorrow) but you're not going to see a lot of people looking for Brunch on a Tuesday.
As the search volume goes down for a term, so do the total number of impressions. As it goes up, so do the total impressions.
Many of our B2B clients see high impressions during the week and almost none on the weekends… why? Because the B's that they are trying to B2 are closed, so the people who work there aren't performing those searches.
I had a client a few years back who had Reiki Massage (and other holistic health services) that could be booked on their web site. Massages like this are luxury items, but targeted toward the middle class. Search volume (and bookings) for the massages were coming in hot on Thursdays and Fridays, but almost nothing during the rest of the week. This one took me a while to figure out, but I finally settled on something fairly obvious… Search volume for something like this with a fairly high price point ($100-$150) for a middle class person is higher on Thursday and Friday because those are the days you get paid. Sure, some people might search during the week to find info about it, but everyone that is ready to book something is going to do it on payday when they have that extra hundred bucks in their pocket.
So first… take a look at search volume for your main search terms or the ones that are actually driving traffic on that day. (I can't be certain from your post, but it LOOKS like your hot day might be Saturday.) If the search volume is up for that day as compared to others – now you have the answer as to why impressions are up.
Keep in mind that regionalities can affect things. Terms like "ski areas near me" are going to be higher on the weekend – but ONLY in areas where it's cold. So the overall volume might not see huge jumps, but if you're located in a cold area, you're seeing a huge portion of that smaller weekend jump that the people in Florida aren't seeing. So what might look like a little blip in overall volume, can work out to be a fairly major blip of the search term is regionally affected.
Now… once you've established whether or not that is the case… then you can start to analyze "why" – be it because "brunch" and "skiing" are done on the weekends or because "reiki massages" only happen on payday.
The answer above isn't specific to you since I don't have enough info to get specific, but hopefully it gives you some things to look at and gives you some insight into "how" to analyze the scenario yourself.
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Petter
Set up datastudio, connect Google Search Console (GSC), pull up the data on device dimension, country dimension, page dimension and query dimension (4 slides, one per slide) and add controls on respective slides for daterange (all) and device/country/query/page (all). This will make it easier to drill down to the root cause of the pattern.
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Dana 🎓
We have a few clients with this – not so dramatic as yours but a few little insights from the world of broadcast advertising…that may or may not be helpful.
Monday to Wednesday – you buy/broadcast ads predominantly for services. Because over the weekend, people have been "getting annoyed by a dripping tap" or "thinking about how they have to do their taxes" or "imagining how they want their new kitchen to look".
Thursday and Friday is PEAK time for retail. People are making mental notes, I have to buy some new shirts this weekend, I have to find a bike for Billy's birthday etc
Weekends is OOH – out of home… for radio and OOH media at least. Car yards. Stop in at 7-11 for a slurpie, stuff you do when you're already in the car. Mostly though it's car shopping. You'll hear it now, all weekend, any radio station, all the ads are for new cars. It's because it's not just that people are shopping right now, it's that when they even START thinking about a new car, they hear the ad and then "see that car everywhere"
When you look at hour of day and day of week in reporting, you may be able to see that these peaks… correspond with hour of day or day of week – probably not in such a new site, they're really defined so it's probably a bot related thing.
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