Often times, the common question arises, what is the difference between sleet and freezing rain? They are actually two very different weather conditions.
Sleet is frozen precipitation that forms into pellets as it falls to the ground. It can often be seen bouncing off of windshields, other objects, and even the ground. Depending on how much there is and the amount of time that it falls, it can accumulate similar to snow. Freezing rain is much different. It falls just like regular rain and does not freeze until it comes in contact with trees, powerline, roads, or other surfaces that are below 32 degrees.
In the event of a sleet weather condition, snow falls and goes through a warm layer, turning it into rain. It then exits the warm layer and hits the cold atmosphere, causing it to refreeze into pellets. This takes place just above the surface of the Earth.
When we have freezing rain conditions, snow falls through a warm layer of atmosphere and then turns to rain. The big difference comes in here; the layer is much bigger and closer to the early. Therefore, the sub-freezing layer is much thinner. Because of this, the rain drops do not have time to freeze into actually pellets. But, because of the freezing temps, the rain freezes upon contact with objects or structures.
Both weather conditions present unfavorable and dangerous conditions. However, the sleet can inflict damage upon things such as cars because of the form it hits the surfaces in. They can both also present dangerous travel conditions by creating icy roadways. Travelers should always use caution when these conditions present themselves. Bridges and overpasses can become extremely dangerous and icy. This is because the cold air not only passes on top of but, below them as well.
Ice, caused by freezing rain, can be measured quite simply. You will need to find a branch, or an object with a visible accumulation of ice on it. Measure the thickest part from the object, to the outer edge. Then, measure the thinnest part, in the same manner. When you are finished, add the two together and divide by two. The result is known as ice accumulation.
Sleet is measured in the same way that you would measure snow. Simply use a ruler. Find an area where there is accumulation. Stick the ruler down as far as it will go. The resulting measurement is your sleet accumulation.