But the wider lockdown could continue beyond March 1.
The study cost £60,000.
Temperatures in Scotland plunged to their coldest level in 25 years – but "weather is not the same as climate".
Move piles pressure on Boris Johnson to impose restrictions beyond "red list" countries.
A mountain rescue team had to be assembled after the two men got into difficulty in Minus Two Gully.
Torrential rain is also expected to affect many parts of the country.
Favourite to lead Labour north of border calls backing the principle of a second referendum a "wheeze of a position".
Nicola Sturgeon to seek "legal referendum" if SNP wins Holyrood election, regardless of whether Boris Johnson agrees.
Mild flooding also occurred at a pharmaceutical plant manufacturing the Oxford/ AstraZeneca coronavirus vaccine, but disruption was averted.
Nicola Sturgeon also cuts click-and-collect services, and imposes new rules about takeaways.