The MMGW people will tell you they account for that. But I have never seen anything that absolutely convinces me of it.
But location can matter in other ways as well. Here in the Ozarks where I live, it gets significantly cooler in the hollows than on hilltops or prairies, and especially at night.
One of my favorite sights in the summer is to see the cool air flow down the stream valleys just after dark. It’s like a river, and fog flows downstream with it because the air above the stream is often cooler than the very top water. It’s like something in a fairy tale.
Where I live, if you want an apple orchard, you’ll plant it on hilltops. But if you want peaches, you’ll plant them in the bottoms because the ground stays cooler in the bottoms longer and you don’t get peach trees blossoming in February only to get the blossoms killed by frost. Or at least that’s your intent. Doesn’t always work.
But if you put your temperature measuring device in any kind of flow-way, you’ll get average lower temperatures year-round than if you put it on a hill top where there’s no downward flow of cool air and more retained radiation from the sun.
Also, strangely enough, rocks matter too. If you measure temperature on rocky ground, you’ll get higher temperatures on average than you will on clearer soil. Same with western slopes versus eastern slopes. Western slopes here are always warmer. So if you want early strawberries here, you’ll plant them on a rocky western slope. But you do run drought risk. If you want walnut trees or pecans, you’ll plant them on an eastern slope. Deeper soil, less droughtiness.
Maybe the people who do all this temperature measuring take those things into account, but I don’t know for a fact that they do.