New official figures from the DVSA – the government body responsible for managing driving tests – show that adverse weather conditions were to blame for 1,140 car test cancellations between November last year and 1 February 2016.
Bad weather also caused 176 motorcycle tests to be cancelled over the same period.
Campaigners say bad weather, an increase in staff retirements and the recent economic upturn have all added to the waiting list backlog.
Across Scotland the average waiting time for a driving test is currently around 10.4 weeks, but in some parts of the country learners are being forced to wait up to four months before they can take their practical test.
In Aberdeen North, drivers have to book their test around 18 weeks in advance, in Dumfries, 17.5 weeks, 16 weeks in Elgin and 12 weeks in Glasgow and Dunfermline.
“It varies from centre to centre and it’s a bit of a lottery where you take your test and how quickly you can be seen,” explained Paul Watters, head of roads policy at AA.
“I’ve heard of waiting lists of up to 20 weeks and obviously the problem is affecting a lot of people.
“It’s about looking at how we can make waiting times quicker, and the DVSA has been looking at ways we can recover, such as incentives for people who take their test at the right time, and cheaper tests at quieter locations.”
Simon Miller, spokesman for the Driving Instructors Association, said a combination of factors – including bad weather – had caused driving test waiting times to increase.
He said: “This is something that concerns our members, firstly due to financial reasons – some students cannot afford to pay for the extra lessons when waiting for the test – and also for practical reasons for a instructor, who may have to predict whether somebody would be ready to take their test quite far in advance.”
DVSA head of operations Phil Lloyd said: “We recognised that short-notice cancellations were very disappointing and work to ensure that tests can go ahead wherever possible. However, we can’t conduct tests in dangerous weather conditions as we have to consider the safety of candidates and staff. If candidates have concerns about weather conditions on the day of their test, they should follow the advice on their appointment confirmation.”