Snow readings vary, but it’s enough for a parking ban
A seasonal parking ban on residential bus routes will take effect at 7 a.m. Friday and continue until snow clearing has been completed, the City of Edmonton announced Thursday.
But those wondering just how much snow fell on the city may have a hard time getting the cold hard facts.
Bob Dunford, director of roadway maintenance, said the significant amount of snow that fell Wednesday led to the ban, which will help crews clear roads faster. “We get about 20 to 25 per cent higher productivity when there’s not vehicles on the road,” he said.
Vehicles still parked on designated parking ban routes after 7 a.m. Friday can be tagged or towed for as long as the ban is in effect — even after snowplows have made an initial pass.
“Just because a grader has gone through, don’t think you’re free to park there if the ban has not been lifted. We often have to go back to a route,” Dunford said.
He urged residents to monitor local media, various social media and the city’s website to stay informed about the status of the ban and other road- clearing news. Also, watch for digital message boards and transit electronic messaging, or sign up for an email notification system.
Once plowing on bus routes has been completed and the parking ban lifted, crews will start a five-day cycle of blading to a level snowpack in city neighbourhoods. That should start early next week.
While Wednesday’s snowfall was enough to lead the city to declare its second parking ban this winter, meteorologists say determining just how much snow landed in the Edmonton area is tricky.
Dan Kulak, a meteorologist with Environment Canada for the last 24 years, said automated weather stations have replaced manned stations.
“We used to have snow courses where ... a person would walk around and stick the ruler in the snow in a number of different locations and take the average, but that’s labour intensive,” Kulak said.
Now technology at stations collects temperatures, rain and snowfall amounts, but such automated systems present challenges. The automatic station at the Edmonton City Centre Airport, for example, reported 2.5 millimetres of precipitation Wednesday, an amount of water that Kulak said is roughly equivalent to 2.5 centimetres of snow — much lower than the 10 to 15 centimetres reported elsewhere in the city.
Nicola Crosbie, chief meteorologist at Global Edmonton, uses friends and family and Twitter followers to help measure snow depth.
“Everybody wants to know how much snow, and I’m literally taking a ruler out in front of the station and measuring it myself,” Crosbie said. “There is very little official way that we can get snow accumulation amounts.”
Wednesday’s snowfall, as recorded by Crosbie’s Twitter followers, ranged from nine centimetres in the west end to 17 centimetres in Millwoods.
Measuring snowfall isn’t a priority for many weather reporting stations, which are operated by NAV Canada and focus on real-time weather, Kulak said. “The pilot who is coming in doesn’t care how much snow is sitting on the side of the runway, he just wants to know that the runway is clear,” Kulak said.
There is one manned weather station just west of Stony Plain. The station recorded 6.4 centimetres of snow Wednesday, which raised the total snowfall for this December to 11.6 centimetres. The station recorded 2.8 centimetres of snow for the first five days of December 2011, and 12.4 centimetres for the month of December in 2011.
The total snowfall for November at the Stony Plain station was 42.8 centimetres, compared to 24 centimetres for November 2011.
Kulak said Environment Canada also uses volunteer observers, people who use an “official snow measuring device — basically a wooden meter stick” to record snowfalls and submit data to Environment Canada.
Environment Canada’s numbers are used by many others, including the City of Edmonton, Dunford said.
CTV meteorologist Josh Classen said the current methods for recording snowfall can make historical comparisons difficult.
“If you want to know how frequently 20-centimetre snowfalls come, and if when you go back through the records there are none, all you’re seeing are five- or six-centimetre snow days because that’s all the automated station reported, that’s not good,” he said.