Can anyone explain this?

[John K Jordan]

The spot is colder for some reason. Some deduction, testing, experimentation, and analysis might suggest why.

I personally think the alien/dog/llama/deer had something to do with it, perhaps something related to marking it's area.

Or if there was sun the day before, the last thing shading the spot could contribute to the heat retained in the surrounding concrete even hours later.

Another possibility is more insulation directly under the patch. The ground temperature a few feet down is equal to the average temperature area over the year. (We use this geothermal heat to keep the automatic livestock waterer from freezing.) No way to know how much heat is there since you live in an undisclosed location. A spot slightly more insulated can prevent heat from below from warming one spot as much as another. It wouldn't take much - a few tenths of a degree could make a difference. For example, a patch of drier gravel/sand containing more air could prevent ground heat from warming that spot compared to the same but wetter surrounding material, perhaps wetter due to water entering from the sides or from below. You could try profiling the area with an IR thermometer but would have to be clever about it. Set up monitoring cameras and track similar snow events to look for similarities (be sure to duplicate the last thing shading the spot.) Drill test holes for temperature monitors. Or get a backhoe and dig up the drive to inspect what's underneath. How much is this bothering you?

Or just move south and never think about it again.

JKJ

[Mel Fulks]

Looks like like someone dropped a bag of Costco baking soda.

[John Goodin]

There has to be some spot where the snow melts last.

[Pat Barry]

Snow doesn't end up the exact depth everywhere. Due to wind flow and blocking by structures, etc there is usually some drifting. Perfectly normal. These drifted locations have deeper snow, thus take a bit longer to melt. Throw in the radiant effects from the sun, shading, etc and you have nature at work. Yes, Its safe to go outside.

[Bill Orbine]

That's a kind of question from someone anxiously waiting for warm weather to arrive!

[John K Jordan]

That's a kind of question from someone anxiously waiting for warm weather to arrive!

Me too. It's down to 44 here this morning, please have appropriate sympathy for our suffering.

[Doug Walls]

--the patch of snow still on the driveway from a brief snowstorm before sun-up. Nowhere except for a few spots on a few roofs does any snow remain, yet there's nearly 1/2" there on the driveway-- why won't it melt?

I'm guessing it probably has something to do with the sun rising & warmer morning temperatures?

Looking at the snow that's still on some of the roof's, It all appears to be on the left-hand side from where the photo was taken. That leads me to think the sunrise probably hits the right-hand side first!


Doug

[Tom M King]

I still think it's mostly to do with wind currents, and eddies. If you notice across the street, that one driveway that still has snow is protected by a higher adjoining yard. The one house that still has snow on the lee side of the roof, with the bare spot over the entry, had wind to wrap around the corner of that two story part to keep that spot clear over the entry.

That spot in the driveway would probably have a swirling eddy over it from a combination of being downwind of the cedar tree next door, the low wall, and any number of other objects.

In short, all those spots had just enough dead air that let a little more snow accumulate than anywhere else in the picture.

This from a very experienced lake sailor.

[Kev Williams]

My BIL parks his car there, from 9am to 3pm. I guess it's possible that his car, shading that part of the driveway for 6 hours while the sun warmed the surrounding cement could account for it. But there was still 2 hours of daylight and another 12 hours for the cement to 'acclimate', I wouldn't have thought it could hold the cold that long?

[Doug Garson]

Is it possible your BIL brushed the snow off his car and that's where it landed>

[Malcolm Schweizer]

Elsa was standing there.
image.jpeg

[James Pallas]

Void under the concrete. Allows that spot not to get heat from the underground. Tap lightly with a hammer there and in another spot. Tone should be a little drum like there and solid on the rest.
Jim

[Myk Rian]

Me too. It's down to 44 here this morning, please have appropriate sympathy for our suffering.

Yeah, I'll send you some from 15º Michigan. What would you accept as an appropriate amount?

[John K Jordan]

Yeah, I'll send you some from 15º Michigan. What would you accept as an appropriate amount?

Yikes, you are FAST! I looked at the weather forecast for tonight, supposed to get down to 26F by daylight.

JKJ

[lowell holmes]

I remember snow back in the 60's in Houston Texas.
I also remember delivering newspapers in Kansas City snow and in Oklahoma snow.
I don't really want to see snow again.