For some health and weather research I'm doing in Minnesota, I was interested in how closely related the weather is at any given day across the state: In a mountainous state like Oregon, I would expect high variance. Less so in Minnesota. It bears out. Looking at Duluth, Fargo/Moorhead, Minneapolis-St.Paul, Albert Lea,St-Cloud, Granite Falls.
Duluth and Fargo, which have slightly higher latitude, have the 'cooler' lines (unsurprisingly) but the degree of alignment is interesting.
I'll repeat for a mountainous state where I might think greater stochasticity would be evident.
Below is a map of the sites listed above (I know they need labels 🙂 ). The shaded area is 85% of the state. For my purposes, I just use the MSP site for exposure. What I gain from this exercise is that that choice is a fairly safe bet to approximate exposure across the shaded area... which in turn is a fairly good approximation for all state case data where specific spatial information is missing.