"Fake News" as it were? That's the one commodity we already have a surplus of.
(No disrespect to Uncle Ed who posted the chart here, it's a reference in its way, but YMMV as always.)
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I don't know that I'd call it fake news...it may well have been really good data from whomever collected it. We just have no way of knowing one way or the other. So as I mentioned, I look at the numbers in file I downloaded from time to time for reference purposes, but I take them with a large grain of salt. In general, they follow the temperature-sensitivity trend you'd expect for single vs double base powders, but I should also point out that it is clearly not the same data set as posted by Uncle Ed; the values are not the same. For the powders I've actually used and recorded my own temperature data, they don't seem to be all that far off, as much I can tell. Because I am generally unsure of it's origin and validity, I choose not to propagate it further, that's all.
In the wider view, I'd say the chances are very good that powder temperature-sensitivity responses are NOT perfectly linear. In other words, velocities may well change more per degree within a given temperature range than another. Further, it could easily be possible that such values might differ in response to other variables, such as cartridge volume, bullet weight, barrel length, etc. So I'm not sure it is even possible (or feasible) to create such a chart that would be useful across a wide range of powders, cartridges, bullet, etc.
Upon returning to Omaha, NE a few years ago, where yearly temp swings are far larger than in San Diego, I have made an effort to chrono my loads routinely at different temperatures, especially when it's cool/cold in early spring/late fall and when it's very hot in July/August. I try to use the information more or less to set "bookends" for the low/high temperature extremes I'm likely to shoot in. If you have a feel for how many tenths of a grain you need to adjust a given load to keep velocity relatively constant at the low/hi bookends, it is relatively simple to make smaller adjustments during the season for smaller temperature fluctuations.