Speaking this afternoon, Ms Sturgeon said that there are 4,323, new cases of COVID-19 reported, compared to 3,189 yesterday.
She said that Scotland could face more restrictions if there is an increase in those who become seriously ill.
The First Minister acknowledged that while the link between higher cases and people becoming seriously ill had become weaker, it had not yet been broken.
She also revealed that around half of all new cases are people under 25.
There are 10 new reported deaths of people who have tested positive. It brings the number of deaths so far to 8080.
Across Scotland 364 people are in hospital with recently confirmed COVID-19, with 43 n intensive care.
The First Minister said: "The link between new cases and serious health harms has weakened significantly, but it has not been completely broken.
"That means the rise in cases in the last week may well result in more people having to go to hospital in the coming days, perhaps requiring intensive care treatment, and, unfortunately, a rise in cases like this will still lead to an increase in numbers of people dying.
"That also means that, if this surge continues, and if it accelerates, and if we start to see evidence of a substantial increase in serious illness as a result, we cannot completely rule out having to reimpose some restrictions."
Speaking of the alarming rise, the First Minister said: "New cases in Scotland have more than doubled over the past week.
"That is one of the sharpest rises we have experienced at any point during the pandemic.
"As a result of that, new cases are now slightly higher than the very high levels we saw in early July. In fact, today’s daily figure is the largest we have ever recorded in a single day.
"Though it is worth remembering that we do more testing now than was the case, certainly, in the early stage of the pandemic.
"Now, we always knew that cases were likely to rise as restrictions eased.
“So, to some extent, what we are seeing now is not entirely unexpected.
"That said, the scale of the increase is still a cause of real concern.”
A total of 4,850,552 people have received the first dose of the Covid vaccination and 3,587,145 have received their second dose.
The First Minister said: "We know that vaccination is making a big difference.
"Indeed, that explains why so many of the new cases we are seeing just now are in younger people less likely to have had both doses of vaccine at this stage. Around half of all new cases are, right now, in people under the age of 25.
"We shouldn’t be complacent about that, of course. Young people can still fall seriously ill from Covid, including, of course, through long Covid - which is something that is still to be fully understood.
"And of course, vaccination, while still hugely effective, doesn't provide anyone - of any age - with 100% protection. In fact around a third of new cases recently have been in people who had had both doses of the vaccine.
"However, vaccination does make all of us somewhat less likely to get Covid - and significantly less likely to fall seriously ill from Covid.
"That means vaccination is still significantly weakening the link between high numbers of new cases and serious harm to people’s health.
"That’s why we are able to take a different, much less restrictive approach to dealing with the virus now than was possible in earlier stages of the pandemic.
And it is worth remembering why it is so important for us to do so, and to seek to continue to do so, if possible.”