The reason it takes so long for snow to melt is because snow requires a lot of energy to be changed from a solid into a liquid.
The snow need sunshine on it as well as a warm enough ground temperature and outside temperature to melt.
When the snow is in a shaded area it also takes longer to melt.
For snow to melt it has to be at least 32 F although in some cases snow may melt when the temperature of the weather is below that as long as the ground is warm enough and at least 32 F or above and sun is shining on the surface.
Rain does help snow melt faster as the rain breaks up the many air pockets that the snow contains.
The melting of the snow is accelerated when the rain falls on the snow and gets into the snows air pockets.
This also allows heat to penetrate into the piles of snow further which increases the melting.
Wind and humidity can also impact the snow melting process.
Rain can and will melt snow at 27 F degrees if the surface that is below the snow is warm enough as well and there's enough sun to help.
However snow may sometimes not melt at 27 degrees depending on the other conditions.
Most often snow melts above 32 F and freezes below 32 F.
The sunnier it is out the faster the snow will melt. '
If the snow is in a shaded area the snow will take longer to melt even if the sun is shining.
Snow squalls are caused by near freezing temperatures at the surface along with the strong convection that develops that has enough moisture to produce whiteout conditions.
The wind also leads to the snow squall as the wind causes intense blowing snow.
Snow squalls can be dangerous for those out driving in them or for people caught in them.
However as long as you're indoors and not outside or on the road the snow squall itself is not dangerous but snow squalls reduce visibility and make it hard to see and cause whiteout conditions.
A snow squall is a weather term that means a sudden moderately heavy snowfall with blowing snow and strong, gusty surface winds.
A snow squall is also most often referred to as a whiteout and is similar to a blizzard but is localized in time or in location and snow accumulations may or may not be significant.
While snow squalls are short in duration, snow squalls can cause whiteouts and poor road conditions.
The NWS issues Snow Squall Warnings to alert you when traveling.
Snow squalls only last anywhere from 30 to 60 minutes too, making them very different from a snowstorm which could last several hours to even days.
Snow squalls can drop moderate to heavy snowfall, quickly lowering visibility to white-out conditions and creating a dangerous travel environment.
The combination of quick reductions in visibility and sudden slick conditions on roadways can often lead to high speed wrecks, pileups, and subsequently injuries and fatalities.
There is also a high economic impact as interstates can be shut down for hours.
If you don't need to be out driving or about in a snow squall it's best to stay home as they can be dangerous.
While a snow squall can occur anywhere that experiences snow, they are most common in the Great Lakes region due to the lake effect on local conditions.
Snow squalls, while also quite predictable, form similarly to summer thunderstorms and therefore their placement cannot be accurately predicted until a few hours ahead of time at best.