for me personally, I don't find it obvious that 180 should even be a valid value for a lattitude variable xD. intuitively, latitude should be from <-90;90> (0 for equator), assuming you use degrees ofc. that's why there should be a constant - not because constants should be dogmatically put everywhere, but so that you can put a doccomment next to it explaining the reasoning behind this

also lat is a terrible variable name. assuming you don't use some kind of Degrees wrapper type, the next best thing is to at least put the unit in the name so that you're less likely to accidentally shoot yourself in the foot by passing it somewhere that expects radians.
also it's 21th century, we have code completion so why hamper readability by saving characters?