A +4C snowfall followed by a -4C overnight freeze turns heavy, wet snow into ice that has the consistency of concrete.
We are from Toronto, Canada, and most of Canada regularly gets snow during the winter. As the snow falls from the sky it accumulates. This accumulation must be removed from the streets, sidewalks and private driveways in order for cars to safely drive on the street and for people to be able to safely walk on the sidewalk. There are times when you can leave the snow on your driveway and clear it away some time later, but in some specific conditions, waiting even 6 hours can make the job multiple times more difficult. These conditions include above freezing temperatures while the snow falls, followed by a quick below 0C freeze overnight, turning wet, heavy snow into a large block of ice.
Shoveling snow can be hard work. Snow looks nice and fluffy, and if it is very cold, like -10C, it is. Unfortunately much snow falls near 0C or above. The snow then partially melts and compacts when it hits the ground, turning to slush. Slush is heavy, partially melted snow. A great number of angina and heart attacks occur while people are shoveling snow.
One needs to be aware of the snow conditions as well as proper lifting mechanics in order to not get hurt. Of course if you are young and fit you can shovel any which way you want, and though you might feel some aches and pains the next day, no major injury should occur. When lifting snow you should bend at the knees and limit bending at the waist. Avoid simultaneously lifting and twisting your back, as this puts undue strain on your back. Reposition your body before you lift to avoid this.
If the snow is heavy a smaller shovel will be easier to handle, While you will be shoveling less snow per shovel and therefore it will take you more time to shovel, a smaller shovel lifts less snow and is easier on your back. If you have a long driveway that will take you more than one hour to shovel, consider a gas-powered snow blower. The snow blower, similar to a lawn mower, with pick up and throw your snow off your driveway and on to your lawn. Pre-season and post-season maintenance is required to keep your machine operating well.
Yesterday’s conditions, Dec 09 2009, here in Toronto were ideal for shoveling snow right away. Conditions, at +4C were quite warm, so the snow was mixed with rain and partially melted. The snow was extremely heavy. Overnight the temperature dropped to -4C, freezing this snow/slush mixture into solid ice. If one did not shovel their driveway yesterday evening, by today the snow would have turned into ice, making removal extremely difficult. Ice on your driveway is as hard as concrete. The ice is also very slippery. If there is no prolonged thaw, where the ice can melt sufficiently to be broken up and removed, this ice can stay on your driveway for months. Once your driveway is frozen and uneven, subsequent snowfalls are more difficult to remove, as the uneven surface makes shoveling more of a challenge. Ice also reflects the sun’s rays, acting as an insulating layer, so your black driveway will not heat up as much and therefore will not as easily aid in melting the ice.
The most optimal solution for above 0C snowfall followed by a below 0C overnight temperature is to shovel as early as possible. A clear driveway is dark, allowing it to absorb the sun’s energy and aid in melting residual snow and ice. Along the same lines as “a stitch in time saves nine”, shoveling at the right time can save you a lot of work.
Addendum 2016 Dec 12: Yesterday we received 15cm of snow. Today’s weather is sunny with a high of +2C. This will partially melt the snow, making it heavy with water. Tonight will fall to -5C and stay below a high of 0C for 5 days. Tonight and the next 5 days will freeze the partially melted snow into a block of ice. In these specific conditions you really need to shovel your snow during the day or any time before tonight’s freeze up. Otherwise it will be really difficult to thaw out the block of ice. Ice reflects sun really well and resists melting.
You need to shovel today. Toronto, Canada, last night 15cm snow fell. Today is a high of +2C, followed by -5C tonight and a high of 0C for the next 5 days. The partially melted snow will freeze up into a block of ice. This is then difficult to remove.
