There’s snow in the forecast for tomorrow. In some ways I’m glad I’m on vacation… in others I’m not. It will be interesting as it unfolds.
Today, the Sun is beating down on bare ground and pavement. This time of year there is significantly more heat energy than a month or two ago. When the snow begins, the first few inches – maybe more – will melt on contact.
After a while, if it snows heavily enough, the ground will cool and snow will stick – but it takes a while and it’s a very tough call with little guidance. Any forecast in this regard, from anyone, is more guess than skill.
There’s one other interesting piece of this puzzle. If you look at a cross section of temperatures through the atmosphere (that’s the box on the very top of the graphic), you’ll see a significant area of temperatures above freezing starting at around 850 MB (near 5,000 feet) and heading up a few thousand feet more. That means a period of sleet, which also tends to keep accumulation down.
With each additional variable in a forecast, you increase the chance for error. As I said… in some ways I’m glad to be on vacation.